diff options
Diffstat (limited to 'Documentation')
94 files changed, 3068 insertions, 581 deletions
diff --git a/Documentation/CodingGuidelines b/Documentation/CodingGuidelines index 45465bc0c9..711cb9171e 100644 --- a/Documentation/CodingGuidelines +++ b/Documentation/CodingGuidelines @@ -175,6 +175,11 @@ For shell scripts specifically (not exhaustive): does not have such a problem. + - Even though "local" is not part of POSIX, we make heavy use of it + in our test suite. We do not use it in scripted Porcelains, and + hopefully nobody starts using "local" before they are reimplemented + in C ;-) + For C programs: @@ -498,7 +503,12 @@ Error Messages - Do not end error messages with a full stop. - - Do not capitalize ("unable to open %s", not "Unable to open %s") + - Do not capitalize the first word, only because it is the first word + in the message ("unable to open %s", not "Unable to open %s"). But + "SHA-3 not supported" is fine, because the reason the first word is + capitalized is not because it is at the beginning of the sentence, + but because the word would be spelled in capital letters even when + it appeared in the middle of the sentence. - Say what the error is first ("cannot open %s", not "%s: cannot open") @@ -541,6 +551,51 @@ Writing Documentation: documentation, please see the documentation-related advice in the Documentation/SubmittingPatches file). + In order to ensure the documentation is inclusive, avoid assuming + that an unspecified example person is male or female, and think + twice before using "he", "him", "she", or "her". Here are some + tips to avoid use of gendered pronouns: + + - Prefer succinctness and matter-of-factly describing functionality + in the abstract. E.g. + + --short:: Emit output in the short-format. + + and avoid something like these overly verbose alternatives: + + --short:: Use this to emit output in the short-format. + --short:: You can use this to get output in the short-format. + --short:: A user who prefers shorter output could.... + --short:: Should a person and/or program want shorter output, he + she/they/it can... + + This practice often eliminates the need to involve human actors in + your description, but it is a good practice regardless of the + avoidance of gendered pronouns. + + - When it becomes awkward to stick to this style, prefer "you" when + addressing the the hypothetical user, and possibly "we" when + discussing how the program might react to the user. E.g. + + You can use this option instead of --xyz, but we might remove + support for it in future versions. + + while keeping in mind that you can probably be less verbose, e.g. + + Use this instead of --xyz. This option might be removed in future + versions. + + - If you still need to refer to an example person that is + third-person singular, you may resort to "singular they" to avoid + "he/she/him/her", e.g. + + A contributor asks their upstream to pull from them. + + Note that this sounds ungrammatical and unnatural to those who + learned that "they" is only used for third-person plural, e.g. + those who learn English as a second language in some parts of the + world. + Every user-visible change should be reflected in the documentation. The same general rule as for code applies -- imitate the existing conventions. diff --git a/Documentation/Makefile b/Documentation/Makefile index 874a01d7a8..f5605b7767 100644 --- a/Documentation/Makefile +++ b/Documentation/Makefile @@ -2,6 +2,8 @@ MAN1_TXT = MAN5_TXT = MAN7_TXT = +HOWTO_TXT = +DOC_DEP_TXT = TECH_DOCS = ARTICLES = SP_ARTICLES = @@ -42,6 +44,11 @@ MAN7_TXT += gittutorial-2.txt MAN7_TXT += gittutorial.txt MAN7_TXT += gitworkflows.txt +HOWTO_TXT += $(wildcard howto/*.txt) + +DOC_DEP_TXT += $(wildcard *.txt) +DOC_DEP_TXT += $(wildcard config/*.txt) + ifdef MAN_FILTER MAN_TXT = $(filter $(MAN_FILTER),$(MAN1_TXT) $(MAN5_TXT) $(MAN7_TXT)) else @@ -91,6 +98,7 @@ TECH_DOCS += technical/multi-pack-index TECH_DOCS += technical/pack-format TECH_DOCS += technical/pack-heuristics TECH_DOCS += technical/pack-protocol +TECH_DOCS += technical/parallel-checkout TECH_DOCS += technical/partial-clone TECH_DOCS += technical/protocol-capabilities TECH_DOCS += technical/protocol-common @@ -131,6 +139,7 @@ ASCIIDOC_CONF = -f asciidoc.conf ASCIIDOC_COMMON = $(ASCIIDOC) $(ASCIIDOC_EXTRA) $(ASCIIDOC_CONF) \ -amanversion=$(GIT_VERSION) \ -amanmanual='Git Manual' -amansource='Git' +ASCIIDOC_DEPS = asciidoc.conf GIT-ASCIIDOCFLAGS TXT_TO_HTML = $(ASCIIDOC_COMMON) -b $(ASCIIDOC_HTML) TXT_TO_XML = $(ASCIIDOC_COMMON) -b $(ASCIIDOC_DOCBOOK) MANPAGE_XSL = manpage-normal.xsl @@ -185,6 +194,7 @@ ASCIIDOC_DOCBOOK = docbook5 ASCIIDOC_EXTRA += -acompat-mode -atabsize=8 ASCIIDOC_EXTRA += -I. -rasciidoctor-extensions ASCIIDOC_EXTRA += -alitdd='&\#x2d;&\#x2d;' +ASCIIDOC_DEPS = asciidoctor-extensions.rb GIT-ASCIIDOCFLAGS DBLATEX_COMMON = XMLTO_EXTRA += --skip-validation XMLTO_EXTRA += -x manpage.xsl @@ -285,10 +295,8 @@ docdep_prereqs = \ mergetools-list.made $(mergetools_txt) \ cmd-list.made $(cmds_txt) -doc.dep : $(docdep_prereqs) $(wildcard *.txt) $(wildcard config/*.txt) build-docdep.perl - $(QUIET_GEN)$(RM) $@+ $@ && \ - $(PERL_PATH) ./build-docdep.perl >$@+ $(QUIET_STDERR) && \ - mv $@+ $@ +doc.dep : $(docdep_prereqs) $(DOC_DEP_TXT) build-docdep.perl + $(QUIET_GEN)$(PERL_PATH) ./build-docdep.perl >$@ $(QUIET_STDERR) ifneq ($(MAKECMDGOALS),clean) -include doc.dep @@ -308,8 +316,7 @@ cmds_txt = cmds-ancillaryinterrogators.txt \ $(cmds_txt): cmd-list.made cmd-list.made: cmd-list.perl ../command-list.txt $(MAN1_TXT) - $(QUIET_GEN)$(RM) $@ && \ - $(PERL_PATH) ./cmd-list.perl ../command-list.txt $(cmds_txt) $(QUIET_STDERR) && \ + $(QUIET_GEN)$(PERL_PATH) ./cmd-list.perl ../command-list.txt $(cmds_txt) $(QUIET_STDERR) && \ date >$@ mergetools_txt = mergetools-diff.txt mergetools-merge.txt @@ -317,7 +324,7 @@ mergetools_txt = mergetools-diff.txt mergetools-merge.txt $(mergetools_txt): mergetools-list.made mergetools-list.made: ../git-mergetool--lib.sh $(wildcard ../mergetools/*) - $(QUIET_GEN)$(RM) $@ && \ + $(QUIET_GEN) \ $(SHELL_PATH) -c 'MERGE_TOOLS_DIR=../mergetools && \ . ../git-mergetool--lib.sh && \ show_tool_names can_diff "* " || :' >mergetools-diff.txt && \ @@ -346,32 +353,23 @@ clean: $(RM) manpage-base-url.xsl $(RM) GIT-ASCIIDOCFLAGS -$(MAN_HTML): %.html : %.txt asciidoc.conf asciidoctor-extensions.rb GIT-ASCIIDOCFLAGS - $(QUIET_ASCIIDOC)$(RM) $@+ $@ && \ - $(TXT_TO_HTML) -d manpage -o $@+ $< && \ - mv $@+ $@ +$(MAN_HTML): %.html : %.txt $(ASCIIDOC_DEPS) + $(QUIET_ASCIIDOC)$(TXT_TO_HTML) -d manpage -o $@ $< -$(OBSOLETE_HTML): %.html : %.txto asciidoc.conf asciidoctor-extensions.rb GIT-ASCIIDOCFLAGS - $(QUIET_ASCIIDOC)$(RM) $@+ $@ && \ - $(TXT_TO_HTML) -o $@+ $< && \ - mv $@+ $@ +$(OBSOLETE_HTML): %.html : %.txto $(ASCIIDOC_DEPS) + $(QUIET_ASCIIDOC)$(TXT_TO_HTML) -o $@ $< manpage-base-url.xsl: manpage-base-url.xsl.in $(QUIET_GEN)sed "s|@@MAN_BASE_URL@@|$(MAN_BASE_URL)|" $< > $@ %.1 %.5 %.7 : %.xml manpage-base-url.xsl $(wildcard manpage*.xsl) - $(QUIET_XMLTO)$(RM) $@ && \ - $(XMLTO) -m $(MANPAGE_XSL) $(XMLTO_EXTRA) man $< + $(QUIET_XMLTO)$(XMLTO) -m $(MANPAGE_XSL) $(XMLTO_EXTRA) man $< -%.xml : %.txt asciidoc.conf asciidoctor-extensions.rb GIT-ASCIIDOCFLAGS - $(QUIET_ASCIIDOC)$(RM) $@+ $@ && \ - $(TXT_TO_XML) -d manpage -o $@+ $< && \ - mv $@+ $@ +%.xml : %.txt $(ASCIIDOC_DEPS) + $(QUIET_ASCIIDOC)$(TXT_TO_XML) -d manpage -o $@ $< user-manual.xml: user-manual.txt user-manual.conf asciidoctor-extensions.rb GIT-ASCIIDOCFLAGS - $(QUIET_ASCIIDOC)$(RM) $@+ $@ && \ - $(TXT_TO_XML) -d book -o $@+ $< && \ - mv $@+ $@ + $(QUIET_ASCIIDOC)$(TXT_TO_XML) -d book -o $@ $< technical/api-index.txt: technical/api-index-skel.txt \ technical/api-index.sh $(patsubst %,%.txt,$(API_DOCS)) @@ -392,46 +390,35 @@ XSLTOPTS += --stringparam html.stylesheet docbook-xsl.css XSLTOPTS += --param generate.consistent.ids 1 user-manual.html: user-manual.xml $(XSLT) - $(QUIET_XSLTPROC)$(RM) $@+ $@ && \ - xsltproc $(XSLTOPTS) -o $@+ $(XSLT) $< && \ - mv $@+ $@ + $(QUIET_XSLTPROC)xsltproc $(XSLTOPTS) -o $@ $(XSLT) $< git.info: user-manual.texi $(QUIET_MAKEINFO)$(MAKEINFO) --no-split -o $@ user-manual.texi user-manual.texi: user-manual.xml - $(QUIET_DB2TEXI)$(RM) $@+ $@ && \ - $(DOCBOOK2X_TEXI) user-manual.xml --encoding=UTF-8 --to-stdout >$@++ && \ - $(PERL_PATH) fix-texi.perl <$@++ >$@+ && \ - rm $@++ && \ - mv $@+ $@ + $(QUIET_DB2TEXI)$(DOCBOOK2X_TEXI) user-manual.xml --encoding=UTF-8 --to-stdout >$@+ && \ + $(PERL_PATH) fix-texi.perl <$@+ >$@ && \ + $(RM) $@+ user-manual.pdf: user-manual.xml - $(QUIET_DBLATEX)$(RM) $@+ $@ && \ - $(DBLATEX) -o $@+ $(DBLATEX_COMMON) $< && \ - mv $@+ $@ + $(QUIET_DBLATEX)$(DBLATEX) -o $@ $(DBLATEX_COMMON) $< gitman.texi: $(MAN_XML) cat-texi.perl texi.xsl - $(QUIET_DB2TEXI)$(RM) $@+ $@ && \ + $(QUIET_DB2TEXI) \ ($(foreach xml,$(sort $(MAN_XML)),xsltproc -o $(xml)+ texi.xsl $(xml) && \ $(DOCBOOK2X_TEXI) --encoding=UTF-8 --to-stdout $(xml)+ && \ - rm $(xml)+ &&) true) > $@++ && \ - $(PERL_PATH) cat-texi.perl $@ <$@++ >$@+ && \ - rm $@++ && \ - mv $@+ $@ + $(RM) $(xml)+ &&) true) > $@+ && \ + $(PERL_PATH) cat-texi.perl $@ <$@+ >$@ && \ + $(RM) $@+ gitman.info: gitman.texi $(QUIET_MAKEINFO)$(MAKEINFO) --no-split --no-validate $*.texi $(patsubst %.txt,%.texi,$(MAN_TXT)): %.texi : %.xml - $(QUIET_DB2TEXI)$(RM) $@+ $@ && \ - $(DOCBOOK2X_TEXI) --to-stdout $*.xml >$@+ && \ - mv $@+ $@ + $(QUIET_DB2TEXI)$(DOCBOOK2X_TEXI) --to-stdout $*.xml >$@ -howto-index.txt: howto-index.sh $(wildcard howto/*.txt) - $(QUIET_GEN)$(RM) $@+ $@ && \ - '$(SHELL_PATH_SQ)' ./howto-index.sh $(sort $(wildcard howto/*.txt)) >$@+ && \ - mv $@+ $@ +howto-index.txt: howto-index.sh $(HOWTO_TXT) + $(QUIET_GEN)'$(SHELL_PATH_SQ)' ./howto-index.sh $(sort $(HOWTO_TXT)) >$@ $(patsubst %,%.html,$(ARTICLES)) : %.html : %.txt $(QUIET_ASCIIDOC)$(TXT_TO_HTML) $*.txt @@ -439,11 +426,10 @@ $(patsubst %,%.html,$(ARTICLES)) : %.html : %.txt WEBDOC_DEST = /pub/software/scm/git/docs howto/%.html: ASCIIDOC_EXTRA += -a git-relative-html-prefix=../ -$(patsubst %.txt,%.html,$(wildcard howto/*.txt)): %.html : %.txt GIT-ASCIIDOCFLAGS - $(QUIET_ASCIIDOC)$(RM) $@+ $@ && \ +$(patsubst %.txt,%.html,$(HOWTO_TXT)): %.html : %.txt GIT-ASCIIDOCFLAGS + $(QUIET_ASCIIDOC) \ sed -e '1,/^$$/d' $< | \ - $(TXT_TO_HTML) - >$@+ && \ - mv $@+ $@ + $(TXT_TO_HTML) - >$@ install-webdoc : html '$(SHELL_PATH_SQ)' ./install-webdoc.sh $(WEBDOC_DEST) @@ -471,11 +457,20 @@ print-man1: @for i in $(MAN1_TXT); do echo $$i; done lint-docs:: - $(QUIET_LINT)$(PERL_PATH) lint-gitlink.perl + $(QUIET_LINT)$(PERL_PATH) lint-gitlink.perl \ + $(HOWTO_TXT) $(DOC_DEP_TXT) \ + --section=1 $(MAN1_TXT) \ + --section=5 $(MAN5_TXT) \ + --section=7 $(MAN7_TXT); \ + $(PERL_PATH) lint-man-end-blurb.perl $(MAN_TXT); \ + $(PERL_PATH) lint-man-section-order.perl $(MAN_TXT); ifeq ($(wildcard po/Makefile),po/Makefile) doc-l10n install-l10n:: $(MAKE) -C po $@ endif +# Delete the target file on error +.DELETE_ON_ERROR: + .PHONY: FORCE diff --git a/Documentation/MyFirstContribution.txt b/Documentation/MyFirstContribution.txt index af0a9da62e..015cf24631 100644 --- a/Documentation/MyFirstContribution.txt +++ b/Documentation/MyFirstContribution.txt @@ -47,7 +47,7 @@ Veteran contributors who are especially interested in helping mentor newcomers are present on the list. In order to avoid search indexers, group membership is required to view messages; anyone can join and no approval is required. -==== https://webchat.freenode.net/#git-devel[#git-devel] on Freenode +==== https://web.libera.chat/#git-devel[#git-devel] on Libera Chat This IRC channel is for conversations between Git contributors. If someone is currently online and knows the answer to your question, you can receive help @@ -827,7 +827,7 @@ either examining recent pull requests where someone has been granted `/allow` (https://github.com/gitgitgadget/git/pulls?utf8=%E2%9C%93&q=is%3Apr+is%3Aopen+%22%2Fallow%22[Search: is:pr is:open "/allow"]), in which case both the author and the person who granted the `/allow` can now `/allow` you, or by inquiring on the -https://webchat.freenode.net/#git-devel[#git-devel] IRC channel on Freenode +https://web.libera.chat/#git-devel[#git-devel] IRC channel on Libera Chat linking your pull request and asking for someone to `/allow` you. If the CI fails, you can update your changes with `git rebase -i` and push your diff --git a/Documentation/MyFirstObjectWalk.txt b/Documentation/MyFirstObjectWalk.txt index 2d10eea7a9..45eb84d8b4 100644 --- a/Documentation/MyFirstObjectWalk.txt +++ b/Documentation/MyFirstObjectWalk.txt @@ -691,7 +691,7 @@ help understand. In our case, that means we omit trees and blobs not directly referenced by `HEAD` or `HEAD`'s history, because we begin the walk with only `HEAD` in the `pending` list.) -First, we'll need to `#include "list-objects-filter-options.h`" and set up the +First, we'll need to `#include "list-objects-filter-options.h"` and set up the `struct list_objects_filter_options` at the top of the function. ---- @@ -779,7 +779,7 @@ Count all the objects within and modify the print statement: while ((oid = oidset_iter_next(&oit))) omitted_count++; - printf("commits %d\nblobs %d\ntags %d\ntrees%d\nomitted %d\n", + printf("commits %d\nblobs %d\ntags %d\ntrees %d\nomitted %d\n", commit_count, blob_count, tag_count, tree_count, omitted_count); ---- diff --git a/Documentation/RelNotes/1.6.0.3.txt b/Documentation/RelNotes/1.6.0.3.txt index ae0577836a..ad36c0f0b7 100644 --- a/Documentation/RelNotes/1.6.0.3.txt +++ b/Documentation/RelNotes/1.6.0.3.txt @@ -50,7 +50,7 @@ Fixes since v1.6.0.2 if the working tree is currently dirty. * "git for-each-ref --format=%(subject)" fixed for commits with no - no newline in the message body. + newline in the message body. * "git remote" fixed to protect printf from user input. diff --git a/Documentation/RelNotes/1.8.4.txt b/Documentation/RelNotes/1.8.4.txt index 255e185af6..2e7529928b 100644 --- a/Documentation/RelNotes/1.8.4.txt +++ b/Documentation/RelNotes/1.8.4.txt @@ -365,7 +365,7 @@ details). (merge 2fbd4f9 mh/maint-lockfile-overflow later to maint). * Invocations of "git checkout" used internally by "git rebase" were - counted as "checkout", and affected later "git checkout -" to the + counted as "checkout", and affected later "git checkout -", which took the user to an unexpected place. (merge 3bed291 rr/rebase-checkout-reflog later to maint). diff --git a/Documentation/RelNotes/2.29.0.txt b/Documentation/RelNotes/2.29.0.txt index 06ba2f803f..1f41302ebb 100644 --- a/Documentation/RelNotes/2.29.0.txt +++ b/Documentation/RelNotes/2.29.0.txt @@ -184,8 +184,8 @@ Performance, Internal Implementation, Development Support etc. the ref backend in use, as its format is much richer than the normal refs, and written directly by "git fetch" as a plain file.. - * An unused binary has been discarded, and and a bunch of commands - have been turned into into built-in. + * An unused binary has been discarded, and a bunch of commands + have been turned into built-in. * A handful of places in in-tree code still relied on being able to execute the git subcommands, especially built-ins, in "git-foo" diff --git a/Documentation/RelNotes/2.32.0.txt b/Documentation/RelNotes/2.32.0.txt index ea220f2a51..87d56fa1aa 100644 --- a/Documentation/RelNotes/2.32.0.txt +++ b/Documentation/RelNotes/2.32.0.txt @@ -7,6 +7,13 @@ Backward compatibility notes * ".gitattributes", ".gitignore", and ".mailmap" files that are symbolic links are ignored. + * "git apply --3way" used to first attempt a straight application, + and only fell back to the 3-way merge algorithm when the stright + application failed. Starting with this version, the command will + first try the 3-way merge algorithm and only when it fails (either + resulting with conflict or the base versions of blobs are missing), + falls back to the usual patch application. + Updates since v2.31 ------------------- @@ -40,11 +47,6 @@ UI, Workflows & Features tweak both the message and the contents, and only the message, respectively. - * When accessing a server with a URL like https://user:pass@site/, we - did not to fall back to the basic authentication with the - credential material embedded in the URL after the "Negotiate" - authentication failed. Now we do. - * "git send-email" learned to honor the core.hooksPath configuration. * "git format-patch -v<n>" learned to allow a reroll count that is @@ -75,6 +77,57 @@ UI, Workflows & Features * The command line completion (in contrib/) has learned that CHERRY_PICK_HEAD is a possible pseudo-ref. + * Userdiff patterns for "Scheme" has been added. + + * "git log" learned "--diff-merges=<style>" option, with an + associated configuration variable log.diffMerges. + + * "git log --format=..." placeholders learned %ah/%ch placeholders to + request the --date=human output. + + * Replace GIT_CONFIG_NOSYSTEM mechanism to decline from reading the + system-wide configuration file with GIT_CONFIG_SYSTEM that lets + users specify from which file to read the system-wide configuration + (setting it to an empty file would essentially be the same as + setting NOSYSTEM), and introduce GIT_CONFIG_GLOBAL to override the + per-user configuration in $HOME/.gitconfig. + + * "git add" and "git rm" learned not to touch those paths that are + outside of sparse checkout. + + * "git rev-list" learns the "--filter=object:type=<type>" option, + which can be used to exclude objects of the given kind from the + packfile generated by pack-objects. + + * The command line completion (in contrib/) for "git stash" has been + updated. + + * "git subtree" updates. + + * It is now documented that "format-patch" skips merges. + + * Options to "git pack-objects" that take numeric values like + --window and --depth should not accept negative values; the input + validation has been tightened. + + * The way the command line specified by the trailer.<token>.command + configuration variable receives the end-user supplied value was + both error prone and misleading. An alternative to achieve the + same goal in a safer and more intuitive way has been added, as + the trailer.<token>.cmd configuration variable, to replace it. + + * "git add -i --dry-run" does not dry-run, which was surprising. The + combination of options has taught to error out. + + * "git push" learns to discover common ancestor with the receiving + end over protocol v2. This will hopefully make "git push" as + efficient as "git fetch" in avoiding objects from getting + transferred unnecessarily. + + * "git mailinfo" (hence "git am") learned the "--quoted-cr" option to + control how lines ending with CRLF wrapped in base64 or qp are + handled. + Performance, Internal Implementation, Development Support etc. @@ -120,6 +173,38 @@ Performance, Internal Implementation, Development Support etc. * The last remnant of gettext-poison has been removed. + * The test framework has been taught to optionally turn the default + merge strategy to "ort" throughout the system where we use + three-way merges internally, like cherry-pick, rebase etc., + primarily to enhance its test coverage (the strategy has been + available as an explicit "-s ort" choice). + + * A bit of code clean-up and a lot of test clean-up around userdiff + area. + + * Handling of "promisor packs" that allows certain objects to be + missing and lazily retrievable has been optimized (a bit). + + * When packet_write() fails, we gave an extra error message + unnecessarily, which has been corrected. + + * The checkout machinery has been taught to perform the actual + write-out of the files in parallel when able. + + * Show errno in the trace output in the error codepath that calls + read_raw_ref method. + + * Effort to make the command line completion (in contrib/) safe with + "set -u" continues. + + * Tweak a few tests for "log --format=..." that show timestamps in + various formats. + + * The reflog expiry machinery has been taught to emit trace events. + + * Over-the-wire protocol learns a new request type to ask for object + sizes given a list of object names. + Fixes since v2.31 ----------------- @@ -209,6 +294,102 @@ Fixes since v2.31 option. (merge c5c0548d79 vs/completion-with-set-u later to maint). + * When "git pack-objects" makes a literal copy of a part of existing + packfile using the reachability bitmaps, its update to the progress + meter was broken. + (merge 8e118e8490 jk/pack-objects-bitmap-progress-fix later to maint). + + * The dependencies for config-list.h and command-list.h were broken + when the former was split out of the latter, which has been + corrected. + (merge 56550ea718 sg/bugreport-fixes later to maint). + + * "git push --quiet --set-upstream" was not quiet when setting the + upstream branch configuration, which has been corrected. + (merge f3cce896a8 ow/push-quiet-set-upstream later to maint). + + * The prefetch task in "git maintenance" assumed that "git fetch" + from any remote would fetch all its local branches, which would + fetch too much if the user is interested in only a subset of + branches there. + (merge 32f67888d8 ds/maintenance-prefetch-fix later to maint). + + * Clarify that pathnames recorded in Git trees are most often (but + not necessarily) encoded in UTF-8. + (merge 9364bf465d ab/pathname-encoding-doc later to maint). + + * "git --config-env var=val cmd" weren't accepted (only + --config-env=var=val was). + (merge c331551ccf ps/config-env-option-with-separate-value later to maint). + + * When the reachability bitmap is in effect, the "do not lose + recently created objects and those that are reachable from them" + safety to protect us from races were disabled by mistake, which has + been corrected. + (merge 2ba582ba4c jk/prune-with-bitmap-fix later to maint). + + * Cygwin pathname handling fix. + (merge bccc37fdc7 ad/cygwin-no-backslashes-in-paths later to maint). + + * "git rebase --[no-]reschedule-failed-exec" did not work well with + its configuration variable, which has been corrected. + (merge e5b32bffd1 ab/rebase-no-reschedule-failed-exec later to maint). + + * Portability fix for command line completion script (in contrib/). + (merge f2acf763e2 si/zsh-complete-comment-fix later to maint). + + * "git repack -A -d" in a partial clone unnecessarily loosened + objects in promisor pack. + + * "git bisect skip" when custom words are used for new/old did not + work, which has been corrected. + + * A few variants of informational message "Already up-to-date" has + been rephrased. + (merge ad9322da03 js/merge-already-up-to-date-message-reword later to maint). + + * "git submodule update --quiet" did not propagate the quiet option + down to underlying "git fetch", which has been corrected. + (merge 62af4bdd42 nc/submodule-update-quiet later to maint). + + * Document that our test can use "local" keyword. + (merge a84fd3bcc6 jc/test-allows-local later to maint). + + * The word-diff mode has been taught to work better with a word + regexp that can match an empty string. + (merge 0324e8fc6b pw/word-diff-zero-width-matches later to maint). + + * "git p4" learned to find branch points more efficiently. + (merge 6b79818bfb jk/p4-locate-branch-point-optim later to maint). + + * When "git update-ref -d" removes a ref that is packed, it left + empty directories under $GIT_DIR/refs/ for + (merge 5f03e5126d wc/packed-ref-removal-cleanup later to maint). + + * "git clean" and "git ls-files -i" had confusion around working on + or showing ignored paths inside an ignored directory, which has + been corrected. + (merge b548f0f156 en/dir-traversal later to maint). + + * The handling of "%(push)" formatting element of "for-each-ref" and + friends was broken when the same codepath started handling + "%(push:<what>)", which has been corrected. + (merge 1e1c4c5eac zh/ref-filter-push-remote-fix later to maint). + + * The bash prompt script (in contrib/) did not work under "set -u". + (merge 5c0cbdb107 en/prompt-under-set-u later to maint). + + * The "chainlint" feature in the test framework is a handy way to + catch common mistakes in writing new tests, but tends to get + expensive. An knob to selectively disable it has been introduced + to help running tests that the developer has not modified. + (merge 2d86a96220 jk/test-chainlint-softer later to maint). + + * The "rev-parse" command did not diagnose the lack of argument to + "--path-format" option, which was introduced in v2.31 era, which + has been corrected. + (merge 99fc555188 wm/rev-parse-path-format-wo-arg later to maint). + * Other code cleanup, docfix, build fix, etc. (merge f451960708 dl/cat-file-doc-cleanup later to maint). (merge 12604a8d0c sv/t9801-test-path-is-file-cleanup later to maint). @@ -223,3 +404,13 @@ Fixes since v2.31 (merge 28e29ee38b jc/doc-format-patch-clarify later to maint). (merge fc12b6fdde fm/user-manual-use-preface later to maint). (merge dba94e3a85 cc/test-helper-bloom-usage-fix later to maint). + (merge 61a7660516 hn/reftable-tables-doc-update later to maint). + (merge 81ed96a9b2 jt/fetch-pack-request-fix later to maint). + (merge 151b6c2dd7 jc/doc-do-not-capitalize-clarification later to maint). + (merge 9160068ac6 js/access-nul-emulation-on-windows later to maint). + (merge 7a14acdbe6 po/diff-patch-doc later to maint). + (merge f91371b948 pw/patience-diff-clean-up later to maint). + (merge 3a7f0908b6 mt/clean-clean later to maint). + (merge d4e2d15a8b ab/streaming-simplify later to maint). + (merge 0e59f7ad67 ah/merge-ort-i18n later to maint). + (merge e6f68f62e0 ls/typofix later to maint). diff --git a/Documentation/RelNotes/2.33.0.txt b/Documentation/RelNotes/2.33.0.txt new file mode 100644 index 0000000000..893c18bfdd --- /dev/null +++ b/Documentation/RelNotes/2.33.0.txt @@ -0,0 +1,279 @@ +Git 2.33 Release Notes +====================== + +Updates since Git 2.32 +---------------------- + +UI, Workflows & Features + + * "git send-email" learned the "--sendmail-cmd" command line option + and the "sendemail.sendmailCmd" configuration variable, which is a + more sensible approach than the current way of repurposing the + "smtp-server" that is meant to name the server to instead name the + command to talk to the server. + + * The userdiff pattern for C# learned the token "record". + + * "git rev-list" learns to omit the "commit <object-name>" header + lines from the output with the `--no-commit-header` option. + + * "git worktree add --lock" learned to record why the worktree is + locked with a custom message. + + +Performance, Internal Implementation, Development Support etc. + + * The code to handle the "--format" option in "for-each-ref" and + friends made too many string comparisons on %(atom)s used in the + format string, which has been corrected by converting them into + enum when the format string is parsed. + + * Use the hashfile API in the codepath that writes the index file to + reduce code duplication. + + * Repeated rename detections in a sequence of mergy operations have + been optimized out for the 'ort' merge strategy. + + * Preliminary clean-up of tests before the main reftable changes + hits the codebase. + + * The backend for "diff -G/-S" has been updated to use pcre2 engine + when available. + + * Use ".DELETE_ON_ERROR" pseudo target to simplify our Makefile. + + * Code cleanup around struct_type_init() functions. + + * "git send-email" optimization. + + * GitHub Actions / CI update. + (merge 0dc787a9f2 js/ci-windows-update later to maint). + + * Object accesses in repositories with many alternate object store + have been optimized. + + * "git log" has been optimized not to waste cycles to load ref + decoration data that may not be needed. + + * Many "printf"-like helper functions we have have been annotated + with __attribute__() to catch placeholder/parameter mismatches. + + * Tests that cover protocol bits have been updated and helpers + used there have been consolidated. + + * The CI gained a new job to run "make sparse" check. + + * "git status" codepath learned to work with sparsely populated index + without hydrating it fully. + + * A guideline for gender neutral documentation has been added. + + * Documentation on "git diff -l<n>" and diff.renameLimit have been + updated, and the defaults for these limits have been raised. + + * The completion support used to offer alternate spelling of options + that exist only for compatibility, which has been corrected. + + * "TEST_OUTPUT_DIRECTORY=there make test" failed to work, which has + been corrected. + + * "git bundle" gained more test coverage. + + * "git read-tree" had a codepath where blobs are fetched one-by-one + from the promisor remote, which has been corrected to fetch in bulk. + + * Rewrite of "git submodule" in C continues. + + * "git checkout" and "git commit" learn to work without unnecessarily + expanding sparse indexes. + + +Fixes since v2.32 +----------------- + + * We historically rejected a very short string as an author name + while accepting a patch e-mail, which has been loosened. + (merge 72ee47ceeb ef/mailinfo-short-name later to maint). + + * The parallel checkout codepath did not initialize object ID field + used to talk to the worker processes in a futureproof way. + + * Rewrite code that triggers undefined behaviour warning. + (merge aafa5df0df jn/size-t-casted-to-off-t-fix later to maint). + + * The description of "fast-forward" in the glossary has been updated. + (merge e22f2daed0 ry/clarify-fast-forward-in-glossary later to maint). + + * Recent "git clone" left a temporary directory behind when the + transport layer returned an failure. + (merge 6aacb7d861 jk/clone-clean-upon-transport-error later to maint). + + * "git fetch" over protocol v2 left its side of the socket open after + it finished speaking, which unnecessarily wasted the resource on + the other side. + (merge ae1a7eefff jk/fetch-pack-v2-half-close-early later to maint). + + * The command line completion (in contrib/) learned that "git diff" + takes the "--anchored" option. + (merge d1e7c2cac9 tb/complete-diff-anchored later to maint). + + * "git-svn" tests assumed that "locale -a", which is used to pick an + available UTF-8 locale, is available everywhere. A knob has been + introduced to allow testers to specify a suitable locale to use. + (merge 482c962de4 dd/svn-test-wo-locale-a later to maint). + + * Update "git subtree" to work better on Windows. + (merge 77f37de39f js/subtree-on-windows-fix later to maint). + + * Remove multimail from contrib/ + (merge f74d11471f js/no-more-multimail later to maint). + + * Make the codebase MSAN clean. + (merge 4dbc55e87d ah/uninitialized-reads-fix later to maint). + + * Work around inefficient glob substitution in older versions of bash + by rewriting parts of a test. + (merge eb87c6f559 jx/t6020-with-older-bash later to maint). + + * Avoid duplicated work while building reachability bitmaps. + (merge aa9ad6fee5 jk/bitmap-tree-optim later to maint). + + * We broke "GIT_SKIP_TESTS=t?000" to skip certain tests in recent + update, which got fixed. + + * The side-band demultiplexer that is used to display progress output + from the remote end did not clear the line properly when the end of + line hits at a packet boundary, which has been corrected. + + * Some test scripts assumed that readlink(1) was universally + installed and available, which is not the case. + (merge 7c0afdf23c jk/test-without-readlink-1 later to maint). + + * Recent update to completion script (in contrib/) broke those who + use the __git_complete helper to define completion to their custom + command. + (merge cea232194d fw/complete-cmd-idx-fix later to maint). + + * Output from some of our tests were affected by the width of the + terminal that they were run in, which has been corrected by + exporting a fixed value in the COLUMNS environment. + (merge c49a177bec ab/fix-columns-to-80-during-tests later to maint). + + * On Windows, mergetool has been taught to find kdiff3.exe just like + it finds winmerge.exe. + (merge 47eb4c6890 ms/mergetools-kdiff3-on-windows later to maint). + + * When we cannot figure out how wide the terminal is, we use a + fallback value of 80 ourselves (which cannot be avoided), but when + we run the pager, we export it in COLUMNS, which forces the pager + to use the hardcoded value, even when the pager is perfectly + capable to figure it out itself. Stop exporting COLUMNS when we + fall back on the hardcoded default value for our own use. + (merge 9b6e2c8b98 js/stop-exporting-bogus-columns later to maint). + + * "git cat-file --batch-all-objects"" misbehaved when "--batch" is in + use and did not ask for certain object traits. + (merge ee02ac6164 zh/cat-file-batch-fix later to maint). + + * Some code and doc clarification around "git push". + + * The "union" conflict resultion variant misbehaved when used with + binary merge driver. + (merge 382b601acd jk/union-merge-binary later to maint). + + * Prevent "git p4" from failing to submit changes to binary file. + (merge 54662d5958 dc/p4-binary-submit-fix later to maint). + + * "git grep --and -e foo" ought to have been diagnosed as an error + but instead segfaulted, which has been corrected. + (merge fe7fe62d8d rs/grep-parser-fix later to maint). + + * The merge code had funny interactions between content based rename + detection and directory rename detection. + (merge 3585d0ea23 en/merge-dir-rename-corner-case-fix later to maint). + + * When rebuilding the multi-pack index file reusing an existing one, + we used to blindly trust the existing file and ended up carrying + corrupted data into the updated file, which has been corrected. + (merge f89ecf7988 tb/midx-use-checksum later to maint). + + * Update the location of system-side configuration file on Windows. + (merge e355307692 js/gfw-system-config-loc-fix later to maint). + + * Code recently added to support common ancestry negotiation during + "git push" did not sanity check its arguments carefully enough. + (merge eff40457a4 ab/fetch-negotiate-segv-fix later to maint). + + * Update the documentation not to assume users are of certain gender + and adds to guidelines to do so. + (merge 46a237f42f ds/gender-neutral-doc later to maint). + + * "git commit --allow-empty-message" won't abort the operation upon + an empty message, but the hint shown in the editor said otherwise. + (merge 6f70f00b4f hj/commit-allow-empty-message later to maint). + + * The code that gives an error message in "git multi-pack-index" when + no subcommand is given tried to print a NULL pointer as a strong, + which has been corrected. + (merge 88617d11f9 tb/reverse-midx later to maint). + + * CI update. + (merge a066a90db6 js/ci-check-whitespace-updates later to maint). + + * Documentation fix for "git pull --rebase=no". + (merge d3236becec fc/pull-no-rebase-merges-theirs-into-ours later to maint). + + * A race between repacking and using pack bitmaps has been corrected. + (merge dc1daacdcc jk/check-pack-valid-before-opening-bitmap later to maint). + + * The local changes stashed by "git merge --autostash" were lost when + the merge failed in certain ways, which has been corrected. + + * Windows rmdir() equivalent behaves differently from POSIX ones in + that when used on a symbolic link that points at a directory, the + target directory gets removed, which has been corrected. + (merge 3e7d4888e5 tb/mingw-rmdir-symlink-to-directory later to maint). + + * Other code cleanup, docfix, build fix, etc. + (merge bfe35a6165 ah/doc-describe later to maint). + (merge f302c1e4aa jc/clarify-revision-range later to maint). + (merge 3127ff90ea tl/fix-packfile-uri-doc later to maint). + (merge a84216c684 jk/doc-color-pager later to maint). + (merge 4e0a64a713 ab/trace2-squelch-gcc-warning later to maint). + (merge 225f7fa847 ps/rev-list-object-type-filter later to maint). + (merge 5317dfeaed dd/honor-users-tar-in-tests later to maint). + (merge ace6d8e3d6 tk/partial-clone-repack-doc later to maint). + (merge 7ba68e0cf1 js/trace2-discard-event-docfix later to maint). + (merge 8603c419d3 fc/doc-default-to-upstream-config later to maint). + (merge 1d72b604ef jk/revision-squelch-gcc-warning later to maint). + (merge abcb66c614 ar/typofix later to maint). + (merge 9853830787 ah/graph-typofix later to maint). + (merge aac578492d ab/config-hooks-path-testfix later to maint). + (merge 98c7656a18 ar/more-typofix later to maint). + (merge 6fb9195f6c jk/doc-max-pack-size later to maint). + (merge 4184cbd635 ar/mailinfo-memcmp-to-skip-prefix later to maint). + (merge 91d2347033 ar/doc-libera-chat-in-my-first-contrib later to maint). + (merge 338abb0f04 ab/cmd-foo-should-return later to maint). + (merge 546096a5cb ab/xdiff-bug-cleanup later to maint). + (merge b7b793d1e7 ab/progress-cleanup later to maint). + (merge d94f9b8e90 ba/object-info later to maint). + (merge 52ff891c03 ar/test-code-cleanup later to maint). + (merge a0538e5c8b dd/document-log-decorate-default later to maint). + (merge ce24797d38 mr/cmake later to maint). + (merge 9eb542f2ee ab/pre-auto-gc-hook-test later to maint). + (merge 9fffc38583 bk/doc-commit-typofix later to maint). + (merge 1cf823d8f0 ks/submodule-cleanup later to maint). + (merge ebbf5d2b70 js/config-mak-windows-pcre-fix later to maint). + (merge 617480d75b hn/refs-iterator-peel-returns-boolean later to maint). + (merge 6a24cc71ed ar/submodule-helper-include-cleanup later to maint). + (merge 5632e838f8 rs/khash-alloc-cleanup later to maint). + (merge b1d87fbaf1 jk/typofix later to maint). + (merge e04170697a ab/gitignore-discovery-doc later to maint). + (merge 8232a0ff48 dl/packet-read-response-end-fix later to maint). + (merge eb448631fb dl/diff-merge-base later to maint). + (merge c510928a25 hn/refs-debug-empty-prefix later to maint). + (merge ddcb189d9d tb/bitmap-type-filter-comment-fix later to maint). + (merge 878b399734 pb/submodule-recurse-doc later to maint). + (merge 734283855f jk/config-env-doc later to maint). + (merge 482e1488a9 ab/getcwd-test later to maint). + (merge f0b922473e ar/doc-markup-fix later to maint). diff --git a/Documentation/RelNotes/2.34.0.txt b/Documentation/RelNotes/2.34.0.txt new file mode 100644 index 0000000000..4cb0b8f4cc --- /dev/null +++ b/Documentation/RelNotes/2.34.0.txt @@ -0,0 +1,135 @@ +Git 2.34 Release Notes +====================== + +Updates since Git 2.33 +---------------------- + +UI, Workflows & Features + + * Pathname expansion (like "~username/") learned a way to specify a + location relative to Git installation (e.g. its $sharedir which is + $(prefix)/share), with "%(prefix)". + + * Use `ort` instead of `recursive` as the default merge strategy. + + * The userdiff pattern for "java" language has been updated. + + +Performance, Internal Implementation, Development Support etc. + + * "git bisect" spawned "git show-branch" only to pretty-print the + title of the commit after checking out the next version to be + tested; this has been rewritten in C. + + * "git add" can work better with the sparse index. + + * Support for ancient versions of cURL library (pre 7.19.4) has been + dropped. + + * A handful of tests that assumed implementation details of files + backend for refs have been cleaned up. + + * trace2 logs learned to show parent process name to see in what + context Git was invoked. + + * Loading of ref tips to prepare for common ancestry negotiation in + "git fetch-pack" has been optimized by taking advantage of the + commit graph when available. + + * Remind developers that the userdiff patterns should be kept simple + and permissive, assuming that the contents they apply are always + syntactically correct. + + * The current implementation of GIT_TEST_FAIL_PREREQS is broken in + that checking for the lack of a prerequisite would not work. Avoid + the use of "if ! test_have_prereq X" in a test script. + + * The revision traversal API has been optimized by taking advantage + of the commit-graph, when available, to determine if a commit is + reachable from any of the existing refs. + + +Fixes since v2.33 +----------------- + + * Input validation of "git pack-objects --stdin-packs" has been + corrected. + (merge 561fa03529 ab/pack-stdin-packs-fix later to maint). + + * Bugfix for common ancestor negotiation recently introduced in "git + push" code path. + (merge 82823118b9 jt/push-negotiation-fixes later to maint). + + * "git pull" had various corner cases that were not well thought out + around its --rebase backend, e.g. "git pull --ff-only" did not stop + but went ahead and rebased when the history on other side is not a + descendant of our history. The series tries to fix them up. + (merge 6f843a3355 en/pull-conflicting-options later to maint). + + * "git apply" miscounted the bytes and failed to read to the end of + binary hunks. + (merge 46d723ce57 jk/apply-binary-hunk-parsing-fix later to maint). + + * "git range-diff" code clean-up. + (merge c4d5907324 jk/range-diff-fixes later to maint). + + * "git commit --fixup" now works with "--edit" again, after it was + broken in v2.32. + (merge 8ef6aad664 jk/commit-edit-fixup-fix later to maint). + + * Use upload-artifacts v1 (instead of v2) for 32-bit linux, as the + new version has a blocker bug for that architecture. + (merge 3cf9bb36bf cb/ci-use-upload-artifacts-v1 later to maint). + + * Checking out all the paths from HEAD during the last conflicted + step in "git rebase" and continuing would cause the step to be + skipped (which is expected), but leaves MERGE_MSG file behind in + $GIT_DIR and confuses the next "git commit", which has been + corrected. + (merge e5ee33e855 pw/rebase-skip-final-fix later to maint). + + * Various bugs in "git rebase -r" have been fixed. + (merge f2563c9ef3 pw/rebase-r-fixes later to maint). + + * mmap() imitation used to call xmalloc() that dies upon malloc() + failure, which has been corrected to just return an error to the + caller to be handled. + (merge 95b4ff3931 rs/git-mmap-uses-malloc later to maint). + + * "git diff --relative" segfaulted and/or produced incorrect result + when there are unmerged paths. + (merge 8174627b3d dd/diff-files-unmerged-fix later to maint). + + * The delayed checkout code path in "git checkout" etc. were chatty + even when --quiet and/or --no-progress options were given. + (merge 7a132c628e mt/quiet-with-delayed-checkout later to maint). + + * "git branch -D <branch>" used to refuse to remove a broken branch + ref that points at a missing commit, which has been corrected. + (merge 597a977489 rs/branch-allow-deleting-dangling later to maint). + + * Build update for Apple clang. + (merge f32c5d3716 cb/makefile-apple-clang later to maint). + + * The parser for the "--nl" option of "git column" has been + corrected. + (merge c93ca46cf5 sg/column-nl later to maint). + + * Other code cleanup, docfix, build fix, etc. + (merge 1d9c8daef8 ab/bundle-doc later to maint). + (merge 81483fe613 en/merge-strategy-docs later to maint). + (merge 626beebdf8 js/log-protocol-version later to maint). + (merge 00e302da76 cb/builtin-merge-format-string-fix later to maint). + (merge ad51ae4dc0 cb/ci-freebsd-update later to maint). + (merge be6444d1ca fc/completion-updates later to maint). + (merge ff7b83f562 ti/tcsh-completion-regression-fix later to maint). + (merge 325b06deda sg/make-fix-ar-invocation later to maint). + (merge bd72824c60 me/t5582-cleanup later to maint). + (merge f6a5af0f62 ga/send-email-sendmail-cmd later to maint). + (merge f58c7468cd ab/ls-remote-packet-trace later to maint). + (merge 0160f7e725 ab/rebase-fatal-fatal-fix later to maint). + (merge a16eb6b1ff js/maintenance-launchctl-fix later to maint). + (merge c21b2511c2 jk/t5323-no-pack-test-fix later to maint). + (merge 5146c2f148 mh/credential-leakfix later to maint). + (merge 1549577338 dd/t6300-wo-gpg-fix later to maint). + (merge 66e905b7dd rs/xopen-reports-open-failures later to maint). diff --git a/Documentation/RelNotes/2.8.0.txt b/Documentation/RelNotes/2.8.0.txt index 27320b6a9f..38453281b8 100644 --- a/Documentation/RelNotes/2.8.0.txt +++ b/Documentation/RelNotes/2.8.0.txt @@ -377,7 +377,7 @@ notes for details). on that order. * "git show 'HEAD:Foo[BAR]Baz'" did not interpret the argument as a - rev, i.e. the object named by the the pathname with wildcard + rev, i.e. the object named by the pathname with wildcard characters in a tree object. (merge aac4fac nd/dwim-wildcards-as-pathspecs later to maint). diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches index 0452db2e67..e409022d93 100644 --- a/Documentation/SubmittingPatches +++ b/Documentation/SubmittingPatches @@ -74,10 +74,9 @@ the feature triggers the new behavior when it should, and to show the feature does not trigger when it shouldn't. After any code change, make sure that the entire test suite passes. -If you have an account at GitHub (and you can get one for free to work -on open source projects), you can use their Travis CI integration to -test your changes on Linux, Mac (and hopefully soon Windows). See -GitHub-Travis CI hints section for details. +Pushing to a fork of https://github.com/git/git will use their CI +integration to test your changes on Linux, Mac and Windows. See the +<<GHCI,GitHub CI>> section for details. Do not forget to update the documentation to describe the updated behavior and make sure that the resulting documentation set formats @@ -117,10 +116,13 @@ If in doubt which identifier to use, run `git log --no-merges` on the files you are modifying to see the current conventions. [[summary-section]] -It's customary to start the remainder of the first line after "area: " -with a lower-case letter. E.g. "doc: clarify...", not "doc: -Clarify...", or "githooks.txt: improve...", not "githooks.txt: -Improve...". +The title sentence after the "area:" prefix omits the full stop at the +end, and its first word is not capitalized unless there is a reason to +capitalize it other than because it is the first word in the sentence. +E.g. "doc: clarify...", not "doc: Clarify...", or "githooks.txt: +improve...", not "githooks.txt: Improve...". But "refs: HEAD is also +treated as a ref" is correct, as we spell `HEAD` in all caps even when +it appears in the middle of a sentence. [[meaningful-message]] The body should provide a meaningful commit message, which: @@ -164,6 +166,85 @@ or, on an older version of Git without support for --pretty=reference: git show -s --date=short --pretty='format:%h (%s, %ad)' <commit> .... +[[sign-off]] +=== Certify your work by adding your `Signed-off-by` trailer + +To improve tracking of who did what, we ask you to certify that you +wrote the patch or have the right to pass it on under the same license +as ours, by "signing off" your patch. Without sign-off, we cannot +accept your patches. + +If (and only if) you certify the below D-C-O: + +[[dco]] +.Developer's Certificate of Origin 1.1 +____ +By making a contribution to this project, I certify that: + +a. The contribution was created in whole or in part by me and I + have the right to submit it under the open source license + indicated in the file; or + +b. The contribution is based upon previous work that, to the best + of my knowledge, is covered under an appropriate open source + license and I have the right under that license to submit that + work with modifications, whether created in whole or in part + by me, under the same open source license (unless I am + permitted to submit under a different license), as indicated + in the file; or + +c. The contribution was provided directly to me by some other + person who certified (a), (b) or (c) and I have not modified + it. + +d. I understand and agree that this project and the contribution + are public and that a record of the contribution (including all + personal information I submit with it, including my sign-off) is + maintained indefinitely and may be redistributed consistent with + this project or the open source license(s) involved. +____ + +you add a "Signed-off-by" trailer to your commit, that looks like +this: + +.... + Signed-off-by: Random J Developer <random@developer.example.org> +.... + +This line can be added by Git if you run the git-commit command with +the -s option. + +Notice that you can place your own `Signed-off-by` trailer when +forwarding somebody else's patch with the above rules for +D-C-O. Indeed you are encouraged to do so. Do not forget to +place an in-body "From: " line at the beginning to properly attribute +the change to its true author (see (2) above). + +This procedure originally came from the Linux kernel project, so our +rule is quite similar to theirs, but what exactly it means to sign-off +your patch differs from project to project, so it may be different +from that of the project you are accustomed to. + +[[real-name]] +Also notice that a real name is used in the `Signed-off-by` trailer. Please +don't hide your real name. + +[[commit-trailers]] +If you like, you can put extra tags at the end: + +. `Reported-by:` is used to credit someone who found the bug that + the patch attempts to fix. +. `Acked-by:` says that the person who is more familiar with the area + the patch attempts to modify liked the patch. +. `Reviewed-by:`, unlike the other tags, can only be offered by the + reviewers themselves when they are completely satisfied with the + patch after a detailed analysis. +. `Tested-by:` is used to indicate that the person applied the patch + and found it to have the desired effect. + +You can also create your own tag or use one that's in common usage +such as "Thanks-to:", "Based-on-patch-by:", or "Mentored-by:". + [[git-tools]] === Generate your patch using Git tools out of your commits. @@ -299,86 +380,6 @@ Do not forget to add trailers such as `Acked-by:`, `Reviewed-by:` and `Tested-by:` lines as necessary to credit people who helped your patch, and "cc:" them when sending such a final version for inclusion. -[[sign-off]] -=== Certify your work by adding your `Signed-off-by` trailer - -To improve tracking of who did what, we ask you to certify that you -wrote the patch or have the right to pass it on under the same license -as ours, by "signing off" your patch. Without sign-off, we cannot -accept your patches. - -If (and only if) you certify the below D-C-O: - -[[dco]] -.Developer's Certificate of Origin 1.1 -____ -By making a contribution to this project, I certify that: - -a. The contribution was created in whole or in part by me and I - have the right to submit it under the open source license - indicated in the file; or - -b. The contribution is based upon previous work that, to the best - of my knowledge, is covered under an appropriate open source - license and I have the right under that license to submit that - work with modifications, whether created in whole or in part - by me, under the same open source license (unless I am - permitted to submit under a different license), as indicated - in the file; or - -c. The contribution was provided directly to me by some other - person who certified (a), (b) or (c) and I have not modified - it. - -d. I understand and agree that this project and the contribution - are public and that a record of the contribution (including all - personal information I submit with it, including my sign-off) is - maintained indefinitely and may be redistributed consistent with - this project or the open source license(s) involved. -____ - -you add a "Signed-off-by" trailer to your commit, that looks like -this: - -.... - Signed-off-by: Random J Developer <random@developer.example.org> -.... - -This line can be added by Git if you run the git-commit command with -the -s option. - -Notice that you can place your own `Signed-off-by` trailer when -forwarding somebody else's patch with the above rules for -D-C-O. Indeed you are encouraged to do so. Do not forget to -place an in-body "From: " line at the beginning to properly attribute -the change to its true author (see (2) above). - -This procedure originally came from the Linux kernel project, so our -rule is quite similar to theirs, but what exactly it means to sign-off -your patch differs from project to project, so it may be different -from that of the project you are accustomed to. - -[[real-name]] -Also notice that a real name is used in the `Signed-off-by` trailer. Please -don't hide your real name. - -[[commit-trailers]] -If you like, you can put extra tags at the end: - -. `Reported-by:` is used to credit someone who found the bug that - the patch attempts to fix. -. `Acked-by:` says that the person who is more familiar with the area - the patch attempts to modify liked the patch. -. `Reviewed-by:`, unlike the other tags, can only be offered by the - reviewer and means that she is completely satisfied that the patch - is ready for application. It is usually offered only after a - detailed review. -. `Tested-by:` is used to indicate that the person applied the patch - and found it to have the desired effect. - -You can also create your own tag or use one that's in common usage -such as "Thanks-to:", "Based-on-patch-by:", or "Mentored-by:". - == Subsystems with dedicated maintainers Some parts of the system have dedicated maintainers with their own @@ -447,13 +448,12 @@ their trees themselves. entitled "What's cooking in git.git" and "What's in git.git" giving the status of various proposed changes. -[[travis]] -== GitHub-Travis CI hints +== GitHub CI[[GHCI]]] -With an account at GitHub (you can get one for free to work on open -source projects), you can use Travis CI to test your changes on Linux, -Mac (and hopefully soon Windows). You can find a successful example -test build here: https://travis-ci.org/git/git/builds/120473209 +With an account at GitHub, you can use GitHub CI to test your changes +on Linux, Mac and Windows. See +https://github.com/git/git/actions/workflows/main.yml for examples of +recent CI runs. Follow these steps for the initial setup: @@ -461,31 +461,18 @@ Follow these steps for the initial setup: You can find detailed instructions how to fork here: https://help.github.com/articles/fork-a-repo/ -. Open the Travis CI website: https://travis-ci.org - -. Press the "Sign in with GitHub" button. - -. Grant Travis CI permissions to access your GitHub account. - You can find more information about the required permissions here: - https://docs.travis-ci.com/user/github-oauth-scopes - -. Open your Travis CI profile page: https://travis-ci.org/profile - -. Enable Travis CI builds for your Git fork. - -After the initial setup, Travis CI will run whenever you push new changes +After the initial setup, CI will run whenever you push new changes to your fork of Git on GitHub. You can monitor the test state of all your -branches here: https://travis-ci.org/__<Your GitHub handle>__/git/branches +branches here: https://github.com/<Your GitHub handle>/git/actions/workflows/main.yml If a branch did not pass all test cases then it is marked with a red -cross. In that case you can click on the failing Travis CI job and -scroll all the way down in the log. Find the line "<-- Click here to see -detailed test output!" and click on the triangle next to the log line -number to expand the detailed test output. Here is such a failing -example: https://travis-ci.org/git/git/jobs/122676187 - -Fix the problem and push your fix to your Git fork. This will trigger -a new Travis CI build to ensure all tests pass. +cross. In that case you can click on the failing job and navigate to +"ci/run-build-and-tests.sh" and/or "ci/print-test-failures.sh". You +can also download "Artifacts" which are tarred (or zipped) archives +with test data relevant for debugging. + +Then fix the problem and push your fix to your GitHub fork. This will +trigger a new CI build to ensure all tests pass. [[mua]] == MUA specific hints diff --git a/Documentation/config.txt b/Documentation/config.txt index bf82766a6a..0c0e6b859f 100644 --- a/Documentation/config.txt +++ b/Documentation/config.txt @@ -298,6 +298,15 @@ pathname:: tilde expansion happens to such a string: `~/` is expanded to the value of `$HOME`, and `~user/` to the specified user's home directory. ++ +If a path starts with `%(prefix)/`, the remainder is interpreted as a +path relative to Git's "runtime prefix", i.e. relative to the location +where Git itself was installed. For example, `%(prefix)/bin/` refers to +the directory in which the Git executable itself lives. If Git was +compiled without runtime prefix support, the compiled-in prefix will be +subsituted instead. In the unlikely event that a literal path needs to +be specified that should _not_ be expanded, it needs to be prefixed by +`./`, like so: `./%(prefix)/bin`. Variables diff --git a/Documentation/config/advice.txt b/Documentation/config/advice.txt index acbd0c09aa..063eec2511 100644 --- a/Documentation/config/advice.txt +++ b/Documentation/config/advice.txt @@ -44,6 +44,9 @@ advice.*:: Shown when linkgit:git-push[1] rejects a forced update of a branch when its remote-tracking ref has updates that we do not have locally. + skippedCherryPicks:: + Shown when linkgit:git-rebase[1] skips a commit that has already + been cherry-picked onto the upstream branch. statusAheadBehind:: Shown when linkgit:git-status[1] computes the ahead/behind counts for a local ref compared to its remote tracking ref, @@ -119,4 +122,8 @@ advice.*:: addEmptyPathspec:: Advice shown if a user runs the add command without providing the pathspec parameter. + updateSparsePath:: + Advice shown when either linkgit:git-add[1] or linkgit:git-rm[1] + is asked to update index entries outside the current sparse + checkout. -- diff --git a/Documentation/config/blame.txt b/Documentation/config/blame.txt index 9468e8599c..4d047c1790 100644 --- a/Documentation/config/blame.txt +++ b/Documentation/config/blame.txt @@ -27,7 +27,7 @@ blame.ignoreRevsFile:: file names will reset the list of ignored revisions. This option will be handled before the command line option `--ignore-revs-file`. -blame.markUnblamables:: +blame.markUnblamableLines:: Mark lines that were changed by an ignored revision that we could not attribute to another commit with a '*' in the output of linkgit:git-blame[1]. diff --git a/Documentation/config/checkout.txt b/Documentation/config/checkout.txt index 2cddf7b4b4..bfbca90f0e 100644 --- a/Documentation/config/checkout.txt +++ b/Documentation/config/checkout.txt @@ -21,3 +21,24 @@ checkout.guess:: Provides the default value for the `--guess` or `--no-guess` option in `git checkout` and `git switch`. See linkgit:git-switch[1] and linkgit:git-checkout[1]. + +checkout.workers:: + The number of parallel workers to use when updating the working tree. + The default is one, i.e. sequential execution. If set to a value less + than one, Git will use as many workers as the number of logical cores + available. This setting and `checkout.thresholdForParallelism` affect + all commands that perform checkout. E.g. checkout, clone, reset, + sparse-checkout, etc. ++ +Note: parallel checkout usually delivers better performance for repositories +located on SSDs or over NFS. For repositories on spinning disks and/or machines +with a small number of cores, the default sequential checkout often performs +better. The size and compression level of a repository might also influence how +well the parallel version performs. + +checkout.thresholdForParallelism:: + When running parallel checkout with a small number of files, the cost + of subprocess spawning and inter-process communication might outweigh + the parallelization gains. This setting allows to define the minimum + number of files for which parallel checkout should be attempted. The + default is 100. diff --git a/Documentation/config/color.txt b/Documentation/config/color.txt index d5daacb13a..e05d520a86 100644 --- a/Documentation/config/color.txt +++ b/Documentation/config/color.txt @@ -127,8 +127,9 @@ color.interactive.<slot>:: interactive commands. color.pager:: - A boolean to enable/disable colored output when the pager is in - use (default is true). + A boolean to specify whether `auto` color modes should colorize + output going to the pager. Defaults to true; set this to false + if your pager does not understand ANSI color codes. color.push:: A boolean to enable/disable color in push errors. May be set to diff --git a/Documentation/config/diff.txt b/Documentation/config/diff.txt index 2d3331f55c..32f84838ac 100644 --- a/Documentation/config/diff.txt +++ b/Documentation/config/diff.txt @@ -118,9 +118,10 @@ diff.orderFile:: relative to the top of the working tree. diff.renameLimit:: - The number of files to consider when performing the copy/rename - detection; equivalent to the 'git diff' option `-l`. This setting - has no effect if rename detection is turned off. + The number of files to consider in the exhaustive portion of + copy/rename detection; equivalent to the 'git diff' option + `-l`. If not set, the default value is currently 1000. This + setting has no effect if rename detection is turned off. diff.renames:: Whether and how Git detects renames. If set to "false", diff --git a/Documentation/config/fetch.txt b/Documentation/config/fetch.txt index 6af6f5edb2..63748c02b7 100644 --- a/Documentation/config/fetch.txt +++ b/Documentation/config/fetch.txt @@ -69,7 +69,8 @@ fetch.negotiationAlgorithm:: setting defaults to "skipping". Unknown values will cause 'git fetch' to error out. + -See also the `--negotiation-tip` option for linkgit:git-fetch[1]. +See also the `--negotiate-only` and `--negotiation-tip` options to +linkgit:git-fetch[1]. fetch.showForcedUpdates:: Set to false to enable `--no-show-forced-updates` in diff --git a/Documentation/config/index.txt b/Documentation/config/index.txt index 7cb50b37e9..75f3a2d105 100644 --- a/Documentation/config/index.txt +++ b/Documentation/config/index.txt @@ -14,6 +14,11 @@ index.recordOffsetTable:: Defaults to 'true' if index.threads has been explicitly enabled, 'false' otherwise. +index.sparse:: + When enabled, write the index using sparse-directory entries. This + has no effect unless `core.sparseCheckout` and + `core.sparseCheckoutCone` are both enabled. Defaults to 'false'. + index.threads:: Specifies the number of threads to spawn when loading the index. This is meant to reduce index load time on multiprocessor machines. diff --git a/Documentation/config/log.txt b/Documentation/config/log.txt index 208d5fdcaa..456eb07800 100644 --- a/Documentation/config/log.txt +++ b/Documentation/config/log.txt @@ -24,6 +24,11 @@ log.excludeDecoration:: the config option can be overridden by the `--decorate-refs` option. +log.diffMerges:: + Set default diff format to be used for merge commits. See + `--diff-merges` in linkgit:git-log[1] for details. + Defaults to `separate`. + log.follow:: If `true`, `git log` will act as if the `--follow` option was used when a single <path> is given. This has the same limitations as `--follow`, diff --git a/Documentation/config/merge.txt b/Documentation/config/merge.txt index cb2ed58907..e27cc63944 100644 --- a/Documentation/config/merge.txt +++ b/Documentation/config/merge.txt @@ -14,7 +14,7 @@ merge.defaultToUpstream:: branches at the remote named by `branch.<current branch>.remote` are consulted, and then they are mapped via `remote.<remote>.fetch` to their corresponding remote-tracking branches, and the tips of - these tracking branches are merged. + these tracking branches are merged. Defaults to true. merge.ff:: By default, Git does not create an extra merge commit when merging @@ -33,10 +33,12 @@ merge.verifySignatures:: include::fmt-merge-msg.txt[] merge.renameLimit:: - The number of files to consider when performing rename detection - during a merge; if not specified, defaults to the value of - diff.renameLimit. This setting has no effect if rename detection - is turned off. + The number of files to consider in the exhaustive portion of + rename detection during a merge. If not specified, defaults + to the value of diff.renameLimit. If neither + merge.renameLimit nor diff.renameLimit are specified, + currently defaults to 7000. This setting has no effect if + rename detection is turned off. merge.renames:: Whether Git detects renames. If set to "false", rename detection diff --git a/Documentation/config/pack.txt b/Documentation/config/pack.txt index c0844d8d8e..763f7af7c4 100644 --- a/Documentation/config/pack.txt +++ b/Documentation/config/pack.txt @@ -99,12 +99,23 @@ pack.packSizeLimit:: packing to a file when repacking, i.e. the git:// protocol is unaffected. It can be overridden by the `--max-pack-size` option of linkgit:git-repack[1]. Reaching this limit results - in the creation of multiple packfiles; which in turn prevents - bitmaps from being created. - The minimum size allowed is limited to 1 MiB. - The default is unlimited. - Common unit suffixes of 'k', 'm', or 'g' are - supported. + in the creation of multiple packfiles. ++ +Note that this option is rarely useful, and may result in a larger total +on-disk size (because Git will not store deltas between packs), as well +as worse runtime performance (object lookup within multiple packs is +slower than a single pack, and optimizations like reachability bitmaps +cannot cope with multiple packs). ++ +If you need to actively run Git using smaller packfiles (e.g., because your +filesystem does not support large files), this option may help. But if +your goal is to transmit a packfile over a medium that supports limited +sizes (e.g., removable media that cannot store the whole repository), +you are likely better off creating a single large packfile and splitting +it using a generic multi-volume archive tool (e.g., Unix `split`). ++ +The minimum size allowed is limited to 1 MiB. The default is unlimited. +Common unit suffixes of 'k', 'm', or 'g' are supported. pack.useBitmaps:: When true, git will use pack bitmaps (if available) when packing diff --git a/Documentation/config/push.txt b/Documentation/config/push.txt index 21b256e0a4..632033638c 100644 --- a/Documentation/config/push.txt +++ b/Documentation/config/push.txt @@ -24,15 +24,14 @@ push.default:: * `tracking` - This is a deprecated synonym for `upstream`. -* `simple` - in centralized workflow, work like `upstream` with an - added safety to refuse to push if the upstream branch's name is - different from the local one. +* `simple` - pushes the current branch with the same name on the remote. + -When pushing to a remote that is different from the remote you normally -pull from, work as `current`. This is the safest option and is suited -for beginners. +If you are working on a centralized workflow (pushing to the same repository you +pull from, which is typically `origin`), then you need to configure an upstream +branch with the same name. + -This mode has become the default in Git 2.0. +This mode is the default since Git 2.0, and is the safest option suited for +beginners. * `matching` - push all branches having the same name on both ends. This makes the repository you are pushing to remember the set of @@ -120,3 +119,10 @@ push.useForceIfIncludes:: `--force-if-includes` as an option to linkgit:git-push[1] in the command line. Adding `--no-force-if-includes` at the time of push overrides this configuration setting. + +push.negotiate:: + If set to "true", attempt to reduce the size of the packfile + sent by rounds of negotiation in which the client and the + server attempt to find commits in common. If "false", Git will + rely solely on the server's ref advertisement to find commits + in common. diff --git a/Documentation/config/sendemail.txt b/Documentation/config/sendemail.txt index cbc5af42fd..50baa5d6bf 100644 --- a/Documentation/config/sendemail.txt +++ b/Documentation/config/sendemail.txt @@ -8,9 +8,6 @@ sendemail.smtpEncryption:: See linkgit:git-send-email[1] for description. Note that this setting is not subject to the 'identity' mechanism. -sendemail.smtpssl (deprecated):: - Deprecated alias for 'sendemail.smtpEncryption = ssl'. - sendemail.smtpsslcertpath:: Path to ca-certificates (either a directory or a single file). Set it to an empty string to disable certificate verification. diff --git a/Documentation/config/stash.txt b/Documentation/config/stash.txt index 413f907cba..9ed775281f 100644 --- a/Documentation/config/stash.txt +++ b/Documentation/config/stash.txt @@ -6,9 +6,9 @@ stash.useBuiltin:: remaining users that setting this now does nothing. stash.showIncludeUntracked:: - If this is set to true, the `git stash show` command without an - option will show the untracked files of a stash entry. Defaults to - false. See description of 'show' command in linkgit:git-stash[1]. + If this is set to true, the `git stash show` command will show + the untracked files of a stash entry. Defaults to false. See + description of 'show' command in linkgit:git-stash[1]. stash.showPatch:: If this is set to true, the `git stash show` command without an diff --git a/Documentation/config/submodule.txt b/Documentation/config/submodule.txt index d7a63c8c12..ee454f8126 100644 --- a/Documentation/config/submodule.txt +++ b/Documentation/config/submodule.txt @@ -58,8 +58,9 @@ submodule.active:: commands. See linkgit:gitsubmodules[7] for details. submodule.recurse:: - Specifies if commands recurse into submodules by default. This - applies to all commands that have a `--recurse-submodules` option + A boolean indicating if commands should enable the `--recurse-submodules` + option by default. + Applies to all commands that support this option (`checkout`, `fetch`, `grep`, `pull`, `push`, `read-tree`, `reset`, `restore` and `switch`) except `clone` and `ls-files`. Defaults to false. diff --git a/Documentation/config/transfer.txt b/Documentation/config/transfer.txt index 505126a780..b49429eb4d 100644 --- a/Documentation/config/transfer.txt +++ b/Documentation/config/transfer.txt @@ -52,13 +52,17 @@ If you have multiple hideRefs values, later entries override earlier ones (and entries in more-specific config files override less-specific ones). + If a namespace is in use, the namespace prefix is stripped from each -reference before it is matched against `transfer.hiderefs` patterns. +reference before it is matched against `transfer.hiderefs` patterns. In +order to match refs before stripping, add a `^` in front of the ref name. If +you combine `!` and `^`, `!` must be specified first. ++ For example, if `refs/heads/master` is specified in `transfer.hideRefs` and the current namespace is `foo`, then `refs/namespaces/foo/refs/heads/master` -is omitted from the advertisements but `refs/heads/master` and -`refs/namespaces/bar/refs/heads/master` are still advertised as so-called -"have" lines. In order to match refs before stripping, add a `^` in front of -the ref name. If you combine `!` and `^`, `!` must be specified first. +is omitted from the advertisements. If `uploadpack.allowRefInWant` is set, +`upload-pack` will treat `want-ref refs/heads/master` in a protocol v2 +`fetch` command as if `refs/namespaces/foo/refs/heads/master` did not exist. +`receive-pack`, on the other hand, will still advertise the object id the +ref is pointing to without mentioning its name (a so-called ".have" line). + Even if you hide refs, a client may still be able to steal the target objects via the techniques described in the "SECURITY" section of the diff --git a/Documentation/config/uploadpack.txt b/Documentation/config/uploadpack.txt index b0d761282c..32fad5bbe8 100644 --- a/Documentation/config/uploadpack.txt +++ b/Documentation/config/uploadpack.txt @@ -59,15 +59,16 @@ uploadpack.allowFilter:: uploadpackfilter.allow:: Provides a default value for unspecified object filters (see: the - below configuration variable). + below configuration variable). If set to `true`, this will also + enable all filters which get added in the future. Defaults to `true`. uploadpackfilter.<filter>.allow:: Explicitly allow or ban the object filter corresponding to `<filter>`, where `<filter>` may be one of: `blob:none`, - `blob:limit`, `tree`, `sparse:oid`, or `combine`. If using - combined filters, both `combine` and all of the nested filter - kinds must be allowed. Defaults to `uploadpackfilter.allow`. + `blob:limit`, `object:type`, `tree`, `sparse:oid`, or `combine`. + If using combined filters, both `combine` and all of the nested + filter kinds must be allowed. Defaults to `uploadpackfilter.allow`. uploadpackfilter.tree.maxDepth:: Only allow `--filter=tree:<n>` when `<n>` is no more than the value of diff --git a/Documentation/diff-generate-patch.txt b/Documentation/diff-generate-patch.txt index 2db8eacc3e..c78063d4f7 100644 --- a/Documentation/diff-generate-patch.txt +++ b/Documentation/diff-generate-patch.txt @@ -11,7 +11,7 @@ linkgit:git-diff-files[1] with the `-p` option produces patch text. You can customize the creation of patch text via the `GIT_EXTERNAL_DIFF` and the `GIT_DIFF_OPTS` environment variables -(see linkgit:git[1]). +(see linkgit:git[1]), and the `diff` attribute (see linkgit:gitattributes[5]). What the -p option produces is slightly different from the traditional diff format: @@ -74,6 +74,11 @@ separate lines indicate the old and the new mode. rename from b rename to a +5. Hunk headers mention the name of the function to which the hunk + applies. See "Defining a custom hunk-header" in + linkgit:gitattributes[5] for details of how to tailor to this to + specific languages. + Combined diff format -------------------- diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt index aa2b5c11f2..c89d530d3d 100644 --- a/Documentation/diff-options.txt +++ b/Documentation/diff-options.txt @@ -34,7 +34,7 @@ endif::git-diff[] endif::git-format-patch[] ifdef::git-log[] ---diff-merges=(off|none|first-parent|1|separate|m|combined|c|dense-combined|cc):: +--diff-merges=(off|none|on|first-parent|1|separate|m|combined|c|dense-combined|cc):: --no-diff-merges:: Specify diff format to be used for merge commits. Default is {diff-merges-default} unless `--first-parent` is in use, in which case @@ -45,17 +45,24 @@ ifdef::git-log[] Disable output of diffs for merge commits. Useful to override implied value. + +--diff-merges=on::: +--diff-merges=m::: +-m::: + This option makes diff output for merge commits to be shown in + the default format. `-m` will produce the output only if `-p` + is given as well. The default format could be changed using + `log.diffMerges` configuration parameter, which default value + is `separate`. ++ --diff-merges=first-parent::: --diff-merges=1::: This option makes merge commits show the full diff with respect to the first parent only. + --diff-merges=separate::: ---diff-merges=m::: --m::: This makes merge commits show the full diff with respect to each of the parents. Separate log entry and diff is generated - for each parent. `-m` doesn't produce any output without `-p`. + for each parent. + --diff-merges=combined::: --diff-merges=c::: @@ -293,11 +300,14 @@ explained for the configuration variable `core.quotePath` (see linkgit:git-config[1]). --name-only:: - Show only names of changed files. + Show only names of changed files. The file names are often encoded in UTF-8. + For more information see the discussion about encoding in the linkgit:git-log[1] + manual page. --name-status:: Show only names and status of changed files. See the description of the `--diff-filter` option on what the status letters mean. + Just like `--name-only` the file names are often encoded in UTF-8. --submodule[=<format>]:: Specify how differences in submodules are shown. When specifying @@ -578,11 +588,17 @@ When used together with `-B`, omit also the preimage in the deletion part of a delete/create pair. -l<num>:: - The `-M` and `-C` options require O(n^2) processing time where n - is the number of potential rename/copy targets. This - option prevents rename/copy detection from running if - the number of rename/copy targets exceeds the specified - number. + The `-M` and `-C` options involve some preliminary steps that + can detect subsets of renames/copies cheaply, followed by an + exhaustive fallback portion that compares all remaining + unpaired destinations to all relevant sources. (For renames, + only remaining unpaired sources are relevant; for copies, all + original sources are relevant.) For N sources and + destinations, this exhaustive check is O(N^2). This option + prevents the exhaustive portion of rename/copy detection from + running if the number of source/destination files involved + exceeds the specified number. Defaults to diff.renameLimit. + Note that a value of 0 is treated as unlimited. ifndef::git-format-patch[] --diff-filter=[(A|C|D|M|R|T|U|X|B)...[*]]:: diff --git a/Documentation/fetch-options.txt b/Documentation/fetch-options.txt index 07783deee3..e967ff1874 100644 --- a/Documentation/fetch-options.txt +++ b/Documentation/fetch-options.txt @@ -62,8 +62,17 @@ The argument to this option may be a glob on ref names, a ref, or the (possibly abbreviated) SHA-1 of a commit. Specifying a glob is equivalent to specifying this option multiple times, one for each matching ref name. + -See also the `fetch.negotiationAlgorithm` configuration variable -documented in linkgit:git-config[1]. +See also the `fetch.negotiationAlgorithm` and `push.negotiate` +configuration variables documented in linkgit:git-config[1], and the +`--negotiate-only` option below. + +--negotiate-only:: + Do not fetch anything from the server, and instead print the + ancestors of the provided `--negotiation-tip=*` arguments, + which we have in common with the server. ++ +Internally this is used to implement the `push.negotiate` option, see +linkgit:git-config[1]. --dry-run:: Show what would be done, without making any changes. @@ -110,6 +119,11 @@ ifndef::git-pull[] setting `fetch.writeCommitGraph`. endif::git-pull[] +--prefetch:: + Modify the configured refspec to place all refs into the + `refs/prefetch/` namespace. See the `prefetch` task in + linkgit:git-maintenance[1]. + -p:: --prune:: Before fetching, remove any remote-tracking references that no diff --git a/Documentation/git-am.txt b/Documentation/git-am.txt index decd8ae122..8714dfcb76 100644 --- a/Documentation/git-am.txt +++ b/Documentation/git-am.txt @@ -15,6 +15,7 @@ SYNOPSIS [--whitespace=<option>] [-C<n>] [-p<n>] [--directory=<dir>] [--exclude=<path>] [--include=<path>] [--reject] [-q | --quiet] [--[no-]scissors] [-S[<keyid>]] [--patch-format=<format>] + [--quoted-cr=<action>] [(<mbox> | <Maildir>)...] 'git am' (--continue | --skip | --abort | --quit | --show-current-patch[=(diff|raw)]) @@ -59,6 +60,9 @@ OPTIONS --no-scissors:: Ignore scissors lines (see linkgit:git-mailinfo[1]). +--quoted-cr=<action>:: + This flag will be passed down to 'git mailinfo' (see linkgit:git-mailinfo[1]). + -m:: --message-id:: Pass the `-m` flag to 'git mailinfo' (see linkgit:git-mailinfo[1]), diff --git a/Documentation/git-branch.txt b/Documentation/git-branch.txt index 94dc9a54f2..5449767121 100644 --- a/Documentation/git-branch.txt +++ b/Documentation/git-branch.txt @@ -118,7 +118,8 @@ OPTIONS Reset <branchname> to <startpoint>, even if <branchname> exists already. Without `-f`, 'git branch' refuses to change an existing branch. In combination with `-d` (or `--delete`), allow deleting the - branch irrespective of its merged status. In combination with + branch irrespective of its merged status, or whether it even + points to a valid commit. In combination with `-m` (or `--move`), allow renaming the branch even if the new branch name already exists, the same applies for `-c` (or `--copy`). diff --git a/Documentation/git-bundle.txt b/Documentation/git-bundle.txt index 53804cad4b..ac0d003835 100644 --- a/Documentation/git-bundle.txt +++ b/Documentation/git-bundle.txt @@ -18,21 +18,48 @@ SYNOPSIS DESCRIPTION ----------- -Some workflows require that one or more branches of development on one -machine be replicated on another machine, but the two machines cannot -be directly connected, and therefore the interactive Git protocols (git, -ssh, http) cannot be used. - -The 'git bundle' command packages objects and references in an archive -at the originating machine, which can then be imported into another -repository using 'git fetch', 'git pull', or 'git clone', -after moving the archive by some means (e.g., by sneakernet). - -As no -direct connection between the repositories exists, the user must specify a -basis for the bundle that is held by the destination repository: the -bundle assumes that all objects in the basis are already in the -destination repository. +Create, unpack, and manipulate "bundle" files. Bundles are used for +the "offline" transfer of Git objects without an active "server" +sitting on the other side of the network connection. + +They can be used to create both incremental and full backups of a +repository, and to relay the state of the references in one repository +to another. + +Git commands that fetch or otherwise "read" via protocols such as +`ssh://` and `https://` can also operate on bundle files. It is +possible linkgit:git-clone[1] a new repository from a bundle, to use +linkgit:git-fetch[1] to fetch from one, and to list the references +contained within it with linkgit:git-ls-remote[1]. There's no +corresponding "write" support, i.e.a 'git push' into a bundle is not +supported. + +See the "EXAMPLES" section below for examples of how to use bundles. + +BUNDLE FORMAT +------------- + +Bundles are `.pack` files (see linkgit:git-pack-objects[1]) with a +header indicating what references are contained within the bundle. + +Like the the packed archive format itself bundles can either be +self-contained, or be created using exclusions. +See the "OBJECT PREREQUISITES" section below. + +Bundles created using revision exclusions are "thin packs" created +using the `--thin` option to linkgit:git-pack-objects[1], and +unbundled using the `--fix-thin` option to linkgit:git-index-pack[1]. + +There is no option to create a "thick pack" when using revision +exclusions, users should not be concerned about the difference. By +using "thin packs" bundles created using exclusions are smaller in +size. That they're "thin" under the hood is merely noted here as a +curiosity, and as a reference to other documentation + +See link:technical/bundle-format.html[the `bundle-format` +documentation] for more details and the discussion of "thin pack" in +link:technical/pack-format.html[the pack format documentation] for +further details. OPTIONS ------- @@ -117,28 +144,88 @@ unbundle <file>:: SPECIFYING REFERENCES --------------------- -'git bundle' will only package references that are shown by -'git show-ref': this includes heads, tags, and remote heads. References -such as `master~1` cannot be packaged, but are perfectly suitable for -defining the basis. More than one reference may be packaged, and more -than one basis can be specified. The objects packaged are those not -contained in the union of the given bases. Each basis can be -specified explicitly (e.g. `^master~10`), or implicitly (e.g. -`master~10..master`, `--since=10.days.ago master`). +Revisions must accompanied by reference names to be packaged in a +bundle. + +More than one reference may be packaged, and more than one set of prerequisite objects can +be specified. The objects packaged are those not contained in the +union of the prerequisites. + +The 'git bundle create' command resolves the reference names for you +using the same rules as `git rev-parse --abbrev-ref=loose`. Each +prerequisite can be specified explicitly (e.g. `^master~10`), or implicitly +(e.g. `master~10..master`, `--since=10.days.ago master`). + +All of these simple cases are OK (assuming we have a "master" and +"next" branch): + +---------------- +$ git bundle create master.bundle master +$ echo master | git bundle create master.bundle --stdin +$ git bundle create master-and-next.bundle master next +$ (echo master; echo next) | git bundle create master-and-next.bundle --stdin +---------------- + +And so are these (and the same but omitted `--stdin` examples): + +---------------- +$ git bundle create recent-master.bundle master~10..master +$ git bundle create recent-updates.bundle master~10..master next~5..next +---------------- + +A revision name or a range whose right-hand-side cannot be resolved to +a reference is not accepted: + +---------------- +$ git bundle create HEAD.bundle $(git rev-parse HEAD) +fatal: Refusing to create empty bundle. +$ git bundle create master-yesterday.bundle master~10..master~5 +fatal: Refusing to create empty bundle. +---------------- + +OBJECT PREREQUISITES +-------------------- + +When creating bundles it is possible to create a self-contained bundle +that can be unbundled in a repository with no common history, as well +as providing negative revisions to exclude objects needed in the +earlier parts of the history. + +Feeding a revision such as `new` to `git bundle create` will create a +bundle file that contains all the objects reachable from the revision +`new`. That bundle can be unbundled in any repository to obtain a full +history that leads to the revision `new`: + +---------------- +$ git bundle create full.bundle new +---------------- + +A revision range such as `old..new` will produce a bundle file that +will require the revision `old` (and any objects reachable from it) +to exist for the bundle to be "unbundle"-able: + +---------------- +$ git bundle create full.bundle old..new +---------------- + +A self-contained bundle without any prerequisites can be extracted +into anywhere, even into an empty repository, or be cloned from +(i.e., `new`, but not `old..new`). -It is very important that the basis used be held by the destination. It is okay to err on the side of caution, causing the bundle file to contain objects already in the destination, as these are ignored when unpacking at the destination. -`git clone` can use any bundle created without negative refspecs -(e.g., `new`, but not `old..new`). If you want to match `git clone --mirror`, which would include your refs such as `refs/remotes/*`, use `--all`. If you want to provide the same set of refs that a clone directly from the source repository would get, use `--branches --tags` for the `<git-rev-list-args>`. +The 'git bundle verify' command can be used to check whether your +recipient repository has the required prerequisite commits for a +bundle. + EXAMPLES -------- @@ -149,7 +236,7 @@ but we can move data from A to B via some mechanism (CD, email, etc.). We want to update R2 with development made on the branch master in R1. To bootstrap the process, you can first create a bundle that does not have -any basis. You can use a tag to remember up to what commit you last +any prerequisites. You can use a tag to remember up to what commit you last processed, in order to make it easy to later update the other repository with an incremental bundle: @@ -200,7 +287,7 @@ machineB$ git pull If you know up to what commit the intended recipient repository should have the necessary objects, you can use that knowledge to specify the -basis, giving a cut-off point to limit the revisions and objects that go +prerequisites, giving a cut-off point to limit the revisions and objects that go in the resulting bundle. The previous example used the lastR2bundle tag for this purpose, but you can use any other options that you would give to the linkgit:git-log[1] command. Here are more examples: @@ -211,7 +298,7 @@ You can use a tag that is present in both: $ git bundle create mybundle v1.0.0..master ---------------- -You can use a basis based on time: +You can use a prerequisite based on time: ---------------- $ git bundle create mybundle --since=10.days master @@ -224,7 +311,7 @@ $ git bundle create mybundle -10 master ---------------- You can run `git-bundle verify` to see if you can extract from a bundle -that was created with a basis: +that was created with a prerequisite: ---------------- $ git bundle verify mybundle diff --git a/Documentation/git-column.txt b/Documentation/git-column.txt index f58e9c43e6..6cea9ab463 100644 --- a/Documentation/git-column.txt +++ b/Documentation/git-column.txt @@ -39,7 +39,7 @@ OPTIONS --indent=<string>:: String to be printed at the beginning of each line. ---nl=<N>:: +--nl=<string>:: String to be printed at the end of each line, including newline character. diff --git a/Documentation/git-commit.txt b/Documentation/git-commit.txt index 340c5fbb48..95fec5f069 100644 --- a/Documentation/git-commit.txt +++ b/Documentation/git-commit.txt @@ -72,7 +72,7 @@ OPTIONS -p:: --patch:: - Use the interactive patch selection interface to chose + Use the interactive patch selection interface to choose which changes to commit. See linkgit:git-add[1] for details. diff --git a/Documentation/git-config.txt b/Documentation/git-config.txt index 4b4cc5c5e8..2dc4bae6da 100644 --- a/Documentation/git-config.txt +++ b/Documentation/git-config.txt @@ -71,6 +71,7 @@ codes are: On success, the command returns the exit code 0. +[[OPTIONS]] OPTIONS ------- @@ -143,7 +144,13 @@ See also <<FILES>>. -f config-file:: --file config-file:: - Use the given config file instead of the one specified by GIT_CONFIG. + For writing options: write to the specified file rather than the + repository `.git/config`. ++ +For reading options: read only from the specified file rather than from all +available files. ++ +See also <<FILES>>. --blob blob:: Similar to `--file` but use the given blob instead of a file. E.g. @@ -325,20 +332,18 @@ All writing options will per default write to the repository specific configuration file. Note that this also affects options like `--replace-all` and `--unset`. *'git config' will only ever change one file at a time*. -You can override these rules either by command-line options or by environment -variables. The `--global`, `--system` and `--worktree` options will limit -the file used to the global, system-wide or per-worktree file respectively. -The `GIT_CONFIG` environment variable has a similar effect, but you -can specify any filename you want. +You can override these rules using the `--global`, `--system`, +`--local`, `--worktree`, and `--file` command-line options; see +<<OPTIONS>> above. ENVIRONMENT ----------- -GIT_CONFIG:: - Take the configuration from the given file instead of .git/config. - Using the "--global" option forces this to ~/.gitconfig. Using the - "--system" option forces this to $(prefix)/etc/gitconfig. +GIT_CONFIG_GLOBAL:: +GIT_CONFIG_SYSTEM:: + Take the configuration from the given files instead from global or + system-level configuration. See linkgit:git[1] for details. GIT_CONFIG_NOSYSTEM:: Whether to skip reading settings from the system-wide @@ -362,6 +367,12 @@ This is useful for cases where you want to spawn multiple git commands with a common configuration but cannot depend on a configuration file, for example when writing scripts. +GIT_CONFIG:: + If no `--file` option is provided to `git config`, use the file + given by `GIT_CONFIG` as if it were provided via `--file`. This + variable has no effect on other Git commands, and is mostly for + historical compatibility; there is generally no reason to use it + instead of the `--file` option. [[EXAMPLES]] EXAMPLES diff --git a/Documentation/git-credential.txt b/Documentation/git-credential.txt index 31c81c4c02..206e3c5f40 100644 --- a/Documentation/git-credential.txt +++ b/Documentation/git-credential.txt @@ -159,3 +159,7 @@ empty string. + Components which are missing from the URL (e.g., there is no username in the example above) will be left unset. + +GIT +--- +Part of the linkgit:git[1] suite diff --git a/Documentation/git-cvsserver.txt b/Documentation/git-cvsserver.txt index 1b1c71ad9d..f2e4a47ebe 100644 --- a/Documentation/git-cvsserver.txt +++ b/Documentation/git-cvsserver.txt @@ -24,6 +24,18 @@ Usage: [verse] 'git-cvsserver' [<options>] [pserver|server] [<directory> ...] +DESCRIPTION +----------- + +This application is a CVS emulation layer for Git. + +It is highly functional. However, not all methods are implemented, +and for those methods that are implemented, +not all switches are implemented. + +Testing has been done using both the CLI CVS client, and the Eclipse CVS +plugin. Most functionality works fine with both of these clients. + OPTIONS ------- @@ -57,18 +69,6 @@ access still needs to be enabled by the `gitcvs.enabled` config option unless `--export-all` was given, too. -DESCRIPTION ------------ - -This application is a CVS emulation layer for Git. - -It is highly functional. However, not all methods are implemented, -and for those methods that are implemented, -not all switches are implemented. - -Testing has been done using both the CLI CVS client, and the Eclipse CVS -plugin. Most functionality works fine with both of these clients. - LIMITATIONS ----------- diff --git a/Documentation/git-describe.txt b/Documentation/git-describe.txt index a88f6ae2c6..c6a79c2a0f 100644 --- a/Documentation/git-describe.txt +++ b/Documentation/git-describe.txt @@ -63,9 +63,10 @@ OPTIONS Automatically implies --tags. --abbrev=<n>:: - Instead of using the default 7 hexadecimal digits as the - abbreviated object name, use <n> digits, or as many digits - as needed to form a unique object name. An <n> of 0 + Instead of using the default number of hexadecimal digits (which + will vary according to the number of objects in the repository with + a default of 7) of the abbreviated object name, use <n> digits, or + as many digits as needed to form a unique object name. An <n> of 0 will suppress long format, only showing the closest tag. --candidates=<n>:: @@ -139,8 +140,11 @@ at the end. The number of additional commits is the number of commits which would be displayed by "git log v1.0.4..parent". -The hash suffix is "-g" + unambiguous abbreviation for the tip commit -of parent (which was `2414721b194453f058079d897d13c4e377f92dc6`). +The hash suffix is "-g" + an unambigous abbreviation for the tip commit +of parent (which was `2414721b194453f058079d897d13c4e377f92dc6`). The +length of the abbreviation scales as the repository grows, using the +approximate number of objects in the repository and a bit of math +around the birthday paradox, and defaults to a minimum of 7. The "g" prefix stands for "git" and is used to allow describing the version of a software depending on the SCM the software is managed with. This is useful in an environment where people may use different SCMs. diff --git a/Documentation/git-diff.txt b/Documentation/git-diff.txt index 7f4c8a8ce7..6236c75c9b 100644 --- a/Documentation/git-diff.txt +++ b/Documentation/git-diff.txt @@ -51,16 +51,20 @@ files on disk. --staged is a synonym of --cached. + If --merge-base is given, instead of using <commit>, use the merge base -of <commit> and HEAD. `git diff --merge-base A` is equivalent to -`git diff $(git merge-base A HEAD)`. +of <commit> and HEAD. `git diff --cached --merge-base A` is equivalent to +`git diff --cached $(git merge-base A HEAD)`. -'git diff' [<options>] <commit> [--] [<path>...]:: +'git diff' [<options>] [--merge-base] <commit> [--] [<path>...]:: This form is to view the changes you have in your working tree relative to the named <commit>. You can use HEAD to compare it with the latest commit, or a branch name to compare with the tip of a different branch. ++ +If --merge-base is given, instead of using <commit>, use the merge base +of <commit> and HEAD. `git diff --merge-base A` is equivalent to +`git diff $(git merge-base A HEAD)`. 'git diff' [<options>] [--merge-base] <commit> <commit> [--] [<path>...]:: diff --git a/Documentation/git-fetch.txt b/Documentation/git-fetch.txt index 9067c2079e..550c16ca61 100644 --- a/Documentation/git-fetch.txt +++ b/Documentation/git-fetch.txt @@ -133,7 +133,7 @@ remember to run that, set `fetch.prune` globally, or linkgit:git-config[1]. Here's where things get tricky and more specific. The pruning feature -doesn't actually care about branches, instead it'll prune local <-> +doesn't actually care about branches, instead it'll prune local <--> remote-references as a function of the refspec of the remote (see `<refspec>` and <<CRTB,CONFIGURED REMOTE-TRACKING BRANCHES>> above). diff --git a/Documentation/git-for-each-ref.txt b/Documentation/git-for-each-ref.txt index 2ae2478de7..6da899c629 100644 --- a/Documentation/git-for-each-ref.txt +++ b/Documentation/git-for-each-ref.txt @@ -235,6 +235,15 @@ and `date` to extract the named component. For email fields (`authoremail`, without angle brackets, and `:localpart` to get the part before the `@` symbol out of the trimmed email. +The raw data in an object is `raw`. + +raw:size:: + The raw data size of the object. + +Note that `--format=%(raw)` can not be used with `--python`, `--shell`, `--tcl`, +because such language may not support arbitrary binary data in their string +variable type. + The message in a commit or a tag object is `contents`, from which `contents:<part>` can be used to extract various parts out of: diff --git a/Documentation/git-format-patch.txt b/Documentation/git-format-patch.txt index 911da181a1..fe2f69d36e 100644 --- a/Documentation/git-format-patch.txt +++ b/Documentation/git-format-patch.txt @@ -36,7 +36,7 @@ SYNOPSIS DESCRIPTION ----------- -Prepare each commit with its "patch" in +Prepare each non-merge commit with its "patch" in one "message" per commit, formatted to resemble a UNIX mailbox. The output of this command is convenient for e-mail submission or for use with 'git am'. @@ -740,6 +740,14 @@ use it only when you know the recipient uses Git to apply your patch. $ git format-patch -3 ------------ +CAVEATS +------- + +Note that `format-patch` will omit merge commits from the output, even +if they are part of the requested range. A simple "patch" does not +include enough information for the receiving end to reproduce the same +merge commit. + SEE ALSO -------- linkgit:git-am[1], linkgit:git-send-email[1] diff --git a/Documentation/git-grep.txt b/Documentation/git-grep.txt index 4e0ba8234a..3d393fbac1 100644 --- a/Documentation/git-grep.txt +++ b/Documentation/git-grep.txt @@ -38,38 +38,6 @@ are lists of one or more search expressions separated by newline characters. An empty string as search expression matches all lines. -CONFIGURATION -------------- - -grep.lineNumber:: - If set to true, enable `-n` option by default. - -grep.column:: - If set to true, enable the `--column` option by default. - -grep.patternType:: - Set the default matching behavior. Using a value of 'basic', 'extended', - 'fixed', or 'perl' will enable the `--basic-regexp`, `--extended-regexp`, - `--fixed-strings`, or `--perl-regexp` option accordingly, while the - value 'default' will return to the default matching behavior. - -grep.extendedRegexp:: - If set to true, enable `--extended-regexp` option by default. This - option is ignored when the `grep.patternType` option is set to a value - other than 'default'. - -grep.threads:: - Number of grep worker threads to use. If unset (or set to 0), Git will - use as many threads as the number of logical cores available. - -grep.fullName:: - If set to true, enable `--full-name` option by default. - -grep.fallbackToNoIndex:: - If set to true, fall back to git grep --no-index if git grep - is executed outside of a git repository. Defaults to false. - - OPTIONS ------- --cached:: @@ -363,6 +331,38 @@ with multiple threads might perform slower than single threaded if `--textconv` is given and there're too many text conversions. So if you experience low performance in this case, it might be desirable to use `--threads=1`. +CONFIGURATION +------------- + +grep.lineNumber:: + If set to true, enable `-n` option by default. + +grep.column:: + If set to true, enable the `--column` option by default. + +grep.patternType:: + Set the default matching behavior. Using a value of 'basic', 'extended', + 'fixed', or 'perl' will enable the `--basic-regexp`, `--extended-regexp`, + `--fixed-strings`, or `--perl-regexp` option accordingly, while the + value 'default' will return to the default matching behavior. + +grep.extendedRegexp:: + If set to true, enable `--extended-regexp` option by default. This + option is ignored when the `grep.patternType` option is set to a value + other than 'default'. + +grep.threads:: + Number of grep worker threads to use. If unset (or set to 0), Git will + use as many threads as the number of logical cores available. + +grep.fullName:: + If set to true, enable `--full-name` option by default. + +grep.fallbackToNoIndex:: + If set to true, fall back to git grep --no-index if git grep + is executed outside of a git repository. Defaults to false. + + GIT --- Part of the linkgit:git[1] suite diff --git a/Documentation/git-interpret-trailers.txt b/Documentation/git-interpret-trailers.txt index 96ec6499f0..956a01d184 100644 --- a/Documentation/git-interpret-trailers.txt +++ b/Documentation/git-interpret-trailers.txt @@ -232,25 +232,38 @@ trailer.<token>.ifmissing:: that option for trailers with the specified <token>. trailer.<token>.command:: - This option can be used to specify a shell command that will - be called to automatically add or modify a trailer with the - specified <token>. + This option behaves in the same way as 'trailer.<token>.cmd', except + that it doesn't pass anything as argument to the specified command. + Instead the first occurrence of substring $ARG is replaced by the + value that would be passed as argument. + -When this option is specified, the behavior is as if a special -'<token>=<value>' argument were added at the beginning of the command -line, where <value> is taken to be the standard output of the -specified command with any leading and trailing whitespace trimmed -off. +The 'trailer.<token>.command' option has been deprecated in favor of +'trailer.<token>.cmd' due to the fact that $ARG in the user's command is +only replaced once and that the original way of replacing $ARG is not safe. + -If the command contains the `$ARG` string, this string will be -replaced with the <value> part of an existing trailer with the same -<token>, if any, before the command is launched. +When both 'trailer.<token>.cmd' and 'trailer.<token>.command' are given +for the same <token>, 'trailer.<token>.cmd' is used and +'trailer.<token>.command' is ignored. + +trailer.<token>.cmd:: + This option can be used to specify a shell command that will be called: + once to automatically add a trailer with the specified <token>, and then + each time a '--trailer <token>=<value>' argument to modify the <value> of + the trailer that this option would produce. + -If some '<token>=<value>' arguments are also passed on the command -line, when a 'trailer.<token>.command' is configured, the command will -also be executed for each of these arguments. And the <value> part of -these arguments, if any, will be used to replace the `$ARG` string in -the command. +When the specified command is first called to add a trailer +with the specified <token>, the behavior is as if a special +'--trailer <token>=<value>' argument was added at the beginning +of the "git interpret-trailers" command, where <value> +is taken to be the standard output of the command with any +leading and trailing whitespace trimmed off. ++ +If some '--trailer <token>=<value>' arguments are also passed +on the command line, the command is called again once for each +of these arguments with the same <token>. And the <value> part +of these arguments, if any, will be passed to the command as its +first argument. This way the command can produce a <value> computed +from the <value> passed in the '--trailer <token>=<value>' argument. EXAMPLES -------- @@ -333,6 +346,55 @@ subject Fix #42 ------------ +* Configure a 'help' trailer with a cmd use a script `glog-find-author` + which search specified author identity from git log in git repository + and show how it works: ++ +------------ +$ cat ~/bin/glog-find-author +#!/bin/sh +test -n "$1" && git log --author="$1" --pretty="%an <%ae>" -1 || true +$ git config trailer.help.key "Helped-by: " +$ git config trailer.help.ifExists "addIfDifferentNeighbor" +$ git config trailer.help.cmd "~/bin/glog-find-author" +$ git interpret-trailers --trailer="help:Junio" --trailer="help:Couder" <<EOF +> subject +> +> message +> +> EOF +subject + +message + +Helped-by: Junio C Hamano <gitster@pobox.com> +Helped-by: Christian Couder <christian.couder@gmail.com> +------------ + +* Configure a 'ref' trailer with a cmd use a script `glog-grep` + to grep last relevant commit from git log in the git repository + and show how it works: ++ +------------ +$ cat ~/bin/glog-grep +#!/bin/sh +test -n "$1" && git log --grep "$1" --pretty=reference -1 || true +$ git config trailer.ref.key "Reference-to: " +$ git config trailer.ref.ifExists "replace" +$ git config trailer.ref.cmd "~/bin/glog-grep" +$ git interpret-trailers --trailer="ref:Add copyright notices." <<EOF +> subject +> +> message +> +> EOF +subject + +message + +Reference-to: 8bc9a0c769 (Add copyright notices., 2005-04-07) +------------ + * Configure a 'see' trailer with a command to show the subject of a commit that is related, and show how it works: + diff --git a/Documentation/git-log.txt b/Documentation/git-log.txt index 1bbf865a1b..0498e7bacb 100644 --- a/Documentation/git-log.txt +++ b/Documentation/git-log.txt @@ -39,7 +39,9 @@ OPTIONS full ref name (including prefix) will be printed. If 'auto' is specified, then if the output is going to a terminal, the ref names are shown as if 'short' were given, otherwise no ref names are - shown. The default option is 'short'. + shown. The option `--decorate` is short-hand for `--decorate=short`. + Default to configuration value of `log.decorate` if configured, + otherwise, `auto`. --decorate-refs=<pattern>:: --decorate-refs-exclude=<pattern>:: diff --git a/Documentation/git-mailinfo.txt b/Documentation/git-mailinfo.txt index d343f040f5..3fcfd965fd 100644 --- a/Documentation/git-mailinfo.txt +++ b/Documentation/git-mailinfo.txt @@ -9,7 +9,9 @@ git-mailinfo - Extracts patch and authorship from a single e-mail message SYNOPSIS -------- [verse] -'git mailinfo' [-k|-b] [-u | --encoding=<encoding> | -n] [--[no-]scissors] <msg> <patch> +'git mailinfo' [-k|-b] [-u | --encoding=<encoding> | -n] + [--[no-]scissors] [--quoted-cr=<action>] + <msg> <patch> DESCRIPTION @@ -89,6 +91,23 @@ This can be enabled by default with the configuration option mailinfo.scissors. --no-scissors:: Ignore scissors lines. Useful for overriding mailinfo.scissors settings. +--quoted-cr=<action>:: + Action when processes email messages sent with base64 or + quoted-printable encoding, and the decoded lines end with a CRLF + instead of a simple LF. ++ +The valid actions are: ++ +-- +* `nowarn`: Git will do nothing when such a CRLF is found. +* `warn`: Git will issue a warning for each message if such a CRLF is + found. +* `strip`: Git will convert those CRLF to LF. +-- ++ +The default action could be set by configuration option `mailinfo.quotedCR`. +If no such configuration option has been set, `warn` will be used. + <msg>:: The commit log message extracted from e-mail, usually except the title line which comes from e-mail Subject. diff --git a/Documentation/git-maintenance.txt b/Documentation/git-maintenance.txt index 80ddd33ceb..1e738ad398 100644 --- a/Documentation/git-maintenance.txt +++ b/Documentation/git-maintenance.txt @@ -92,10 +92,8 @@ commit-graph:: prefetch:: The `prefetch` task updates the object directory with the latest objects from all registered remotes. For each remote, a `git fetch` - command is run. The refmap is custom to avoid updating local or remote - branches (those in `refs/heads` or `refs/remotes`). Instead, the - remote refs are stored in `refs/prefetch/<remote>/`. Also, tags are - not updated. + command is run. The configured refspec is modified to place all + requested refs within `refs/prefetch/`. Also, tags are not updated. + This is done to avoid disrupting the remote-tracking branches. The end users expect these refs to stay unmoved unless they initiate a fetch. With prefetch diff --git a/Documentation/git-merge.txt b/Documentation/git-merge.txt index 3819fadac1..e4f3352eb5 100644 --- a/Documentation/git-merge.txt +++ b/Documentation/git-merge.txt @@ -61,6 +61,8 @@ merge has resulted in conflicts. OPTIONS ------- +:git-merge: 1 + include::merge-options.txt[] -m <msg>:: diff --git a/Documentation/git-mktag.txt b/Documentation/git-mktag.txt index 17a2603a60..466a697519 100644 --- a/Documentation/git-mktag.txt +++ b/Documentation/git-mktag.txt @@ -11,14 +11,6 @@ SYNOPSIS [verse] 'git mktag' -OPTIONS -------- - ---strict:: - By default mktag turns on the equivalent of - linkgit:git-fsck[1] `--strict` mode. Use `--no-strict` to - disable it. - DESCRIPTION ----------- @@ -45,6 +37,14 @@ the appropriate `fsck.<msg-id>` varible: git -c fsck.extraHeaderEntry=ignore mktag <my-tag-with-headers +OPTIONS +------- + +--strict:: + By default mktag turns on the equivalent of + linkgit:git-fsck[1] `--strict` mode. Use `--no-strict` to + disable it. + Tag Format ---------- A tag signature file, to be fed to this command's standard input, diff --git a/Documentation/git-p4.txt b/Documentation/git-p4.txt index f89e68b424..38e5257b2a 100644 --- a/Documentation/git-p4.txt +++ b/Documentation/git-p4.txt @@ -762,3 +762,7 @@ IMPLEMENTATION DETAILS message indicating the p4 depot location and change number. This line is used by later 'git p4 sync' operations to know which p4 changes are new. + +GIT +--- +Part of the linkgit:git[1] suite diff --git a/Documentation/git-pack-objects.txt b/Documentation/git-pack-objects.txt index 25d9fbe37a..dbfd1f9017 100644 --- a/Documentation/git-pack-objects.txt +++ b/Documentation/git-pack-objects.txt @@ -128,10 +128,10 @@ depth is 4095. into multiple independent packfiles, each not larger than the given size. The size can be suffixed with "k", "m", or "g". The minimum size allowed is limited to 1 MiB. - This option - prevents the creation of a bitmap index. The default is unlimited, unless the config variable - `pack.packSizeLimit` is set. + `pack.packSizeLimit` is set. Note that this option may result in + a larger and slower repository; see the discussion in + `pack.packSizeLimit`. --honor-pack-keep:: This flag causes an object already in a local pack that diff --git a/Documentation/git-pull.txt b/Documentation/git-pull.txt index 5c3fb67c01..aef757ec89 100644 --- a/Documentation/git-pull.txt +++ b/Documentation/git-pull.txt @@ -15,14 +15,17 @@ SYNOPSIS DESCRIPTION ----------- -Incorporates changes from a remote repository into the current -branch. In its default mode, `git pull` is shorthand for -`git fetch` followed by `git merge FETCH_HEAD`. - -More precisely, 'git pull' runs 'git fetch' with the given -parameters and calls 'git merge' to merge the retrieved branch -heads into the current branch. -With `--rebase`, it runs 'git rebase' instead of 'git merge'. +Incorporates changes from a remote repository into the current branch. +If the current branch is behind the remote, then by default it will +fast-forward the current branch to match the remote. If the current +branch and the remote have diverged, the user needs to specify how to +reconcile the divergent branches with `--rebase` or `--no-rebase` (or +the corresponding configuration option in `pull.rebase`). + +More precisely, `git pull` runs `git fetch` with the given parameters +and then depending on configuration options or command line flags, +will call either `git rebase` or `git merge` to reconcile diverging +branches. <repository> should be the name of a remote repository as passed to linkgit:git-fetch[1]. <refspec> can name an @@ -117,7 +120,7 @@ When set to `preserve` (deprecated in favor of `merges`), rebase with the `--preserve-merges` option passed to `git rebase` so that locally created merge commits will not be flattened. + -When false, merge the current branch into the upstream branch. +When false, merge the upstream branch into the current branch. + When `interactive`, enable the interactive mode of rebase. + @@ -132,7 +135,7 @@ published that history already. Do *not* use this option unless you have read linkgit:git-rebase[1] carefully. --no-rebase:: - Override earlier --rebase. + This is shorthand for --rebase=false. Options related to fetching ~~~~~~~~~~~~~~~~~~~~~~~~~~~ diff --git a/Documentation/git-push.txt b/Documentation/git-push.txt index a953c7c387..2f25aa3a29 100644 --- a/Documentation/git-push.txt +++ b/Documentation/git-push.txt @@ -244,8 +244,8 @@ Imagine that you have to rebase what you have already published. You will have to bypass the "must fast-forward" rule in order to replace the history you originally published with the rebased history. If somebody else built on top of your original history while you are -rebasing, the tip of the branch at the remote may advance with her -commit, and blindly pushing with `--force` will lose her work. +rebasing, the tip of the branch at the remote may advance with their +commit, and blindly pushing with `--force` will lose their work. + This option allows you to say that you expect the history you are updating is what you rebased and want to replace. If the remote ref diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt index f08ae27e2a..506345cb0e 100644 --- a/Documentation/git-rebase.txt +++ b/Documentation/git-rebase.txt @@ -79,9 +79,10 @@ remain the checked-out branch. If the upstream branch already contains a change you have made (e.g., because you mailed a patch which was applied upstream), then that commit -will be skipped. For example, running `git rebase master` on the -following history (in which `A'` and `A` introduce the same set of changes, -but have different committer information): +will be skipped and warnings will be issued (if the `merge` backend is +used). For example, running `git rebase master` on the following +history (in which `A'` and `A` introduce the same set of changes, but +have different committer information): ------------ A---B---C topic @@ -200,12 +201,6 @@ Alternatively, you can undo the 'git rebase' with git rebase --abort -CONFIGURATION -------------- - -include::config/rebase.txt[] -include::config/sequencer.txt[] - OPTIONS ------- --onto <newbase>:: @@ -318,7 +313,10 @@ See also INCOMPATIBLE OPTIONS below. By default (or if `--no-reapply-cherry-picks` is given), these commits will be automatically dropped. Because this necessitates reading all upstream commits, this can be expensive in repos with a large number -of upstream commits that need to be read. +of upstream commits that need to be read. When using the `merge` +backend, warnings will be issued for each dropped commit (unless +`--quiet` is given). Advice will also be issued unless +`advice.skippedCherryPicks` is set to false (see linkgit:git-config[1]). + `--reapply-cherry-picks` allows rebase to forgo reading all upstream commits, potentially improving performance. @@ -346,9 +344,7 @@ See also INCOMPATIBLE OPTIONS below. -m:: --merge:: - Use merging strategies to rebase. When the recursive (default) merge - strategy is used, this allows rebase to be aware of renames on the - upstream side. This is the default. + Using merging strategies to rebase (default). + Note that a rebase merge works by replaying each commit from the working branch on top of the <upstream> branch. Because of this, when a merge @@ -360,9 +356,8 @@ See also INCOMPATIBLE OPTIONS below. -s <strategy>:: --strategy=<strategy>:: - Use the given merge strategy. - If there is no `-s` option 'git merge-recursive' is used - instead. This implies --merge. + Use the given merge strategy, instead of the default `ort`. + This implies `--merge`. + Because 'git rebase' replays each commit from the working branch on top of the <upstream> branch using the given strategy, using @@ -375,7 +370,7 @@ See also INCOMPATIBLE OPTIONS below. --strategy-option=<strategy-option>:: Pass the <strategy-option> through to the merge strategy. This implies `--merge` and, if no strategy has been - specified, `-s recursive`. Note the reversal of 'ours' and + specified, `-s ort`. Note the reversal of 'ours' and 'theirs' as noted above for the `-m` option. + See also INCOMPATIBLE OPTIONS below. @@ -536,7 +531,7 @@ The `--rebase-merges` mode is similar in spirit to the deprecated where commits can be reordered, inserted and dropped at will. + It is currently only possible to recreate the merge commits using the -`recursive` merge strategy; Different merge strategies can be used only via +`ort` merge strategy; different merge strategies can be used only via explicit `exec git merge -s <strategy> [...]` commands. + See also REBASING MERGES and INCOMPATIBLE OPTIONS below. @@ -623,6 +618,14 @@ See also INCOMPATIBLE OPTIONS below. --no-reschedule-failed-exec:: Automatically reschedule `exec` commands that failed. This only makes sense in interactive mode (or when an `--exec` option was provided). ++ +Even though this option applies once a rebase is started, it's set for +the whole rebase at the start based on either the +`rebase.rescheduleFailedExec` configuration (see linkgit:git-config[1] +or "CONFIGURATION" below) or whether this option is +provided. Otherwise an explicit `--no-reschedule-failed-exec` at the +start would be overridden by the presence of +`rebase.rescheduleFailedExec=true` configuration. INCOMPATIBLE OPTIONS -------------------- @@ -1217,12 +1220,16 @@ successful merge so that the user can edit the message. If a `merge` command fails for any reason other than merge conflicts (i.e. when the merge operation did not even start), it is rescheduled immediately. -At this time, the `merge` command will *always* use the `recursive` -merge strategy for regular merges, and `octopus` for octopus merges, -with no way to choose a different one. To work around -this, an `exec` command can be used to call `git merge` explicitly, -using the fact that the labels are worktree-local refs (the ref -`refs/rewritten/onto` would correspond to the label `onto`, for example). +By default, the `merge` command will use the `ort` merge strategy for +regular merges, and `octopus` for octopus merges. One can specify a +default strategy for all merges using the `--strategy` argument when +invoking rebase, or can override specific merges in the interactive +list of commands by using an `exec` command to call `git merge` +explicitly with a `--strategy` argument. Note that when calling `git +merge` explicitly like this, you can make use of the fact that the +labels are worktree-local refs (the ref `refs/rewritten/onto` would +correspond to the label `onto`, for example) in order to refer to the +branches you want to merge. Note: the first command (`label onto`) labels the revision onto which the commits are rebased; The name `onto` is just a convention, as a nod @@ -1266,6 +1273,12 @@ merge tlsv1.3 merge cmake ------------ +CONFIGURATION +------------- + +include::config/rebase.txt[] +include::config/sequencer.txt[] + BUGS ---- The todo list presented by the deprecated `--preserve-merges --interactive` diff --git a/Documentation/git-repack.txt b/Documentation/git-repack.txt index 317d63cf0d..24c00c9384 100644 --- a/Documentation/git-repack.txt +++ b/Documentation/git-repack.txt @@ -121,7 +121,9 @@ depth is 4095. If specified, multiple packfiles may be created, which also prevents the creation of a bitmap index. The default is unlimited, unless the config variable - `pack.packSizeLimit` is set. + `pack.packSizeLimit` is set. Note that this option may result in + a larger and slower repository; see the discussion in + `pack.packSizeLimit`. -b:: --write-bitmap-index:: @@ -186,7 +188,7 @@ When `--unpacked` is specified, loose objects are implicitly included in this "roll-up", without respect to their reachability. This is subject to change in the future. This option (implying a drastically different repack mode) is not guaranteed to work with all other combinations of -option to `git repack`). +option to `git repack`. CONFIGURATION ------------- diff --git a/Documentation/git-rm.txt b/Documentation/git-rm.txt index ab750367fd..26e9b28470 100644 --- a/Documentation/git-rm.txt +++ b/Documentation/git-rm.txt @@ -23,7 +23,9 @@ branch, and no updates to their contents can be staged in the index, though that default behavior can be overridden with the `-f` option. When `--cached` is given, the staged content has to match either the tip of the branch or the file on disk, -allowing the file to be removed from just the index. +allowing the file to be removed from just the index. When +sparse-checkouts are in use (see linkgit:git-sparse-checkout[1]), +`git rm` will only remove paths within the sparse-checkout patterns. OPTIONS diff --git a/Documentation/git-send-email.txt b/Documentation/git-send-email.txt index 93708aefea..3db4eab4ba 100644 --- a/Documentation/git-send-email.txt +++ b/Documentation/git-send-email.txt @@ -167,6 +167,14 @@ Sending `sendemail.envelopeSender` configuration variable; if that is unspecified, choosing the envelope sender is left to your MTA. +--sendmail-cmd=<command>:: + Specify a command to run to send the email. The command should + be sendmail-like; specifically, it must support the `-i` option. + The command will be executed in the shell if necessary. Default + is the value of `sendemail.sendmailcmd`. If unspecified, and if + --smtp-server is also unspecified, git-send-email will search + for `sendmail` in `/usr/sbin`, `/usr/lib` and $PATH. + --smtp-encryption=<encryption>:: Specify the encryption to use, either 'ssl' or 'tls'. Any other value reverts to plain SMTP. Default is the value of @@ -211,13 +219,16 @@ a password is obtained using 'git-credential'. --smtp-server=<host>:: If set, specifies the outgoing SMTP server to use (e.g. - `smtp.example.com` or a raw IP address). Alternatively it can - specify a full pathname of a sendmail-like program instead; - the program must support the `-i` option. Default value can - be specified by the `sendemail.smtpServer` configuration - option; the built-in default is to search for `sendmail` in - `/usr/sbin`, `/usr/lib` and $PATH if such program is - available, falling back to `localhost` otherwise. + `smtp.example.com` or a raw IP address). If unspecified, and if + `--sendmail-cmd` is also unspecified, the default is to search + for `sendmail` in `/usr/sbin`, `/usr/lib` and $PATH if such a + program is available, falling back to `localhost` otherwise. ++ +For backward compatibility, this option can also specify a full pathname +of a sendmail-like program instead; the program must support the `-i` +option. This method does not support passing arguments or using plain +command names. For those use cases, consider using `--sendmail-cmd` +instead. --smtp-server-port=<port>:: Specifies a port different from the default port (SMTP diff --git a/Documentation/git-sparse-checkout.txt b/Documentation/git-sparse-checkout.txt index a0eeaeb02e..fdcf43f87c 100644 --- a/Documentation/git-sparse-checkout.txt +++ b/Documentation/git-sparse-checkout.txt @@ -45,6 +45,20 @@ To avoid interfering with other worktrees, it first enables the When `--cone` is provided, the `core.sparseCheckoutCone` setting is also set, allowing for better performance with a limited set of patterns (see 'CONE PATTERN SET' below). ++ +Use the `--[no-]sparse-index` option to toggle the use of the sparse +index format. This reduces the size of the index to be more closely +aligned with your sparse-checkout definition. This can have significant +performance advantages for commands such as `git status` or `git add`. +This feature is still experimental. Some commands might be slower with +a sparse index until they are properly integrated with the feature. ++ +**WARNING:** Using a sparse index requires modifying the index in a way +that is not completely understood by external tools. If you have trouble +with this compatibility, then run `git sparse-checkout init --no-sparse-index` +to rewrite your index to not be sparse. Older versions of Git will not +understand the sparse directory entries index extension and may fail to +interact with your repository until it is disabled. 'set':: Write a set of patterns to the sparse-checkout file, as given as diff --git a/Documentation/git-stash.txt b/Documentation/git-stash.txt index a8c8c32f1e..be6084ccef 100644 --- a/Documentation/git-stash.txt +++ b/Documentation/git-stash.txt @@ -91,8 +91,10 @@ show [-u|--include-untracked|--only-untracked] [<diff-options>] [<stash>]:: By default, the command shows the diffstat, but it will accept any format known to 'git diff' (e.g., `git stash show -p stash@{1}` to view the second most recent entry in patch form). - You can use stash.showIncludeUntracked, stash.showStat, and - stash.showPatch config variables to change the default behavior. + If no `<diff-option>` is provided, the default behavior will be given + by the `stash.showStat`, and `stash.showPatch` config variables. You + can also use `stash.showIncludeUntracked` to set whether + `--include-untracked` is enabled by default. pop [--index] [-q|--quiet] [<stash>]:: diff --git a/Documentation/git-svn.txt b/Documentation/git-svn.txt index 67b143cc81..d5776ffcfd 100644 --- a/Documentation/git-svn.txt +++ b/Documentation/git-svn.txt @@ -1061,25 +1061,6 @@ with different name spaces. For example: branches = stable/*:refs/remotes/svn/stable/* branches = debug/*:refs/remotes/svn/debug/* -BUGS ----- - -We ignore all SVN properties except svn:executable. Any unhandled -properties are logged to $GIT_DIR/svn/<refname>/unhandled.log - -Renamed and copied directories are not detected by Git and hence not -tracked when committing to SVN. I do not plan on adding support for -this as it's quite difficult and time-consuming to get working for all -the possible corner cases (Git doesn't do it, either). Committing -renamed and copied files is fully supported if they're similar enough -for Git to detect them. - -In SVN, it is possible (though discouraged) to commit changes to a tag -(because a tag is just a directory copy, thus technically the same as a -branch). When cloning an SVN repository, 'git svn' cannot know if such a -commit to a tag will happen in the future. Thus it acts conservatively -and imports all SVN tags as branches, prefixing the tag name with 'tags/'. - CONFIGURATION ------------- @@ -1166,6 +1147,25 @@ $GIT_DIR/svn/\**/.rev_map.*:: if it is missing or not up to date. 'git svn reset' automatically rewinds it. +BUGS +---- + +We ignore all SVN properties except svn:executable. Any unhandled +properties are logged to $GIT_DIR/svn/<refname>/unhandled.log + +Renamed and copied directories are not detected by Git and hence not +tracked when committing to SVN. I do not plan on adding support for +this as it's quite difficult and time-consuming to get working for all +the possible corner cases (Git doesn't do it, either). Committing +renamed and copied files is fully supported if they're similar enough +for Git to detect them. + +In SVN, it is possible (though discouraged) to commit changes to a tag +(because a tag is just a directory copy, thus technically the same as a +branch). When cloning an SVN repository, 'git svn' cannot know if such a +commit to a tag will happen in the future. Thus it acts conservatively +and imports all SVN tags as branches, prefixing the tag name with 'tags/'. + SEE ALSO -------- linkgit:git-rebase[1] diff --git a/Documentation/git-worktree.txt b/Documentation/git-worktree.txt index f1bb1fa5f5..8a7cbdd19c 100644 --- a/Documentation/git-worktree.txt +++ b/Documentation/git-worktree.txt @@ -9,7 +9,7 @@ git-worktree - Manage multiple working trees SYNOPSIS -------- [verse] -'git worktree add' [-f] [--detach] [--checkout] [--lock] [-b <new-branch>] <path> [<commit-ish>] +'git worktree add' [-f] [--detach] [--checkout] [--lock [--reason <string>]] [-b <new-branch>] <path> [<commit-ish>] 'git worktree list' [--porcelain] 'git worktree lock' [--reason <string>] <worktree> 'git worktree move' <worktree> <new-path> @@ -242,7 +242,7 @@ With `list`, annotate missing working trees as prunable if they are older than `<time>`. --reason <string>:: - With `lock`, an explanation why the working tree is locked. + With `lock` or with `add --lock`, an explanation why the working tree is locked. <worktree>:: Working trees can be identified by path, either relative or @@ -387,7 +387,7 @@ These annotations are: ------------ $ git worktree list /path/to/linked-worktree abcd1234 [master] -/path/to/locked-worktreee acbd5678 (brancha) locked +/path/to/locked-worktree acbd5678 (brancha) locked /path/to/prunable-worktree 5678abc (detached HEAD) prunable ------------ diff --git a/Documentation/git.txt b/Documentation/git.txt index 3a9c44987f..6dd241ef83 100644 --- a/Documentation/git.txt +++ b/Documentation/git.txt @@ -13,7 +13,7 @@ SYNOPSIS [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path] [-p|--paginate|-P|--no-pager] [--no-replace-objects] [--bare] [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>] - [--super-prefix=<path>] [--config-env <name>=<envvar>] + [--super-prefix=<path>] [--config-env=<name>=<envvar>] <command> [<args>] DESCRIPTION @@ -670,6 +670,16 @@ for further details. If this environment variable is set to `0`, git will not prompt on the terminal (e.g., when asking for HTTP authentication). +`GIT_CONFIG_GLOBAL`:: +`GIT_CONFIG_SYSTEM`:: + Take the configuration from the given files instead from global or + system-level configuration files. If `GIT_CONFIG_SYSTEM` is set, the + system config file defined at build time (usually `/etc/gitconfig`) + will not be read. Likewise, if `GIT_CONFIG_GLOBAL` is set, neither + `$HOME/.gitconfig` nor `$XDG_CONFIG_HOME/git/config` will be read. Can + be set to `/dev/null` to skip reading configuration files of the + respective level. + `GIT_CONFIG_NOSYSTEM`:: Whether to skip reading settings from the system-wide `$(prefix)/etc/gitconfig` file. This environment variable can diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt index 0a60472bb5..83fd4e19a4 100644 --- a/Documentation/gitattributes.txt +++ b/Documentation/gitattributes.txt @@ -845,6 +845,8 @@ patterns are available: - `rust` suitable for source code in the Rust language. +- `scheme` suitable for source code in the Scheme language. + - `tex` suitable for source code for LaTeX documents. @@ -1245,6 +1247,12 @@ to: [attr]binary -diff -merge -text ------------ +NOTES +----- + +Git does not follow symbolic links when accessing a `.gitattributes` +file in the working tree. This keeps behavior consistent when the file +is accessed from the index or a tree versus from the filesystem. EXAMPLES -------- diff --git a/Documentation/gitfaq.txt b/Documentation/gitfaq.txt index afdaeab850..8c1f2d5675 100644 --- a/Documentation/gitfaq.txt +++ b/Documentation/gitfaq.txt @@ -275,7 +275,7 @@ best to always use a regular merge commit. [[merge-two-revert-one]] If I make a change on two branches but revert it on one, why does the merge of those branches include the change?:: - By default, when Git does a merge, it uses a strategy called the recursive + By default, when Git does a merge, it uses a strategy called the `ort` strategy, which does a fancy three-way merge. In such a case, when Git performs the merge, it considers exactly three points: the two heads and a third point, called the _merge base_, which is usually the common ancestor of diff --git a/Documentation/gitignore.txt b/Documentation/gitignore.txt index 5751603b13..f8a1fc2014 100644 --- a/Documentation/gitignore.txt +++ b/Documentation/gitignore.txt @@ -27,12 +27,11 @@ precedence, the last matching pattern decides the outcome): them. * Patterns read from a `.gitignore` file in the same directory - as the path, or in any parent directory, with patterns in the - higher level files (up to the toplevel of the work tree) being overridden - by those in lower level files down to the directory containing the file. - These patterns match relative to the location of the - `.gitignore` file. A project normally includes such - `.gitignore` files in its repository, containing patterns for + as the path, or in any parent directory (up to the top-level of the working + tree), with patterns in the higher level files being overridden by those in + lower level files down to the directory containing the file. These patterns + match relative to the location of the `.gitignore` file. A project normally + includes such `.gitignore` files in its repository, containing patterns for files generated as part of the project build. * Patterns read from `$GIT_DIR/info/exclude`. @@ -149,6 +148,10 @@ not tracked by Git remain untracked. To stop tracking a file that is currently tracked, use 'git rm --cached'. +Git does not follow symbolic links when accessing a `.gitignore` file in +the working tree. This keeps behavior consistent when the file is +accessed from the index or a tree versus from the filesystem. + EXAMPLES -------- diff --git a/Documentation/gitmailmap.txt b/Documentation/gitmailmap.txt index 3fb39f801f..06f4af93fe 100644 --- a/Documentation/gitmailmap.txt +++ b/Documentation/gitmailmap.txt @@ -55,6 +55,13 @@ this would also match the 'Commit Name <commit@email.xx>' above: Proper Name <proper@email.xx> CoMmIt NaMe <CoMmIt@EmAiL.xX> -- +NOTES +----- + +Git does not follow symbolic links when accessing a `.mailmap` file in +the working tree. This keeps behavior consistent when the file is +accessed from the index or a tree versus from the filesystem. + EXAMPLES -------- diff --git a/Documentation/gitmodules.txt b/Documentation/gitmodules.txt index 8e333dde1b..dcee09b500 100644 --- a/Documentation/gitmodules.txt +++ b/Documentation/gitmodules.txt @@ -98,6 +98,14 @@ submodule.<name>.shallow:: shallow clone (with a history depth of 1) unless the user explicitly asks for a non-shallow clone. +NOTES +----- + +Git does not allow the `.gitmodules` file within a working tree to be a +symbolic link, and will refuse to check out such a tree entry. This +keeps behavior consistent when the file is accessed from the index or a +tree versus from the filesystem, and helps Git reliably enforce security +checks of the file contents. EXAMPLES -------- diff --git a/Documentation/gitnamespaces.txt b/Documentation/gitnamespaces.txt index b614969ad2..1c8d2ecc35 100644 --- a/Documentation/gitnamespaces.txt +++ b/Documentation/gitnamespaces.txt @@ -62,3 +62,7 @@ git clone ext::'git --namespace=foo %s /tmp/prefixed.git' ---------- include::transfer-data-leaks.txt[] + +GIT +--- +Part of the linkgit:git[1] suite diff --git a/Documentation/gittutorial.txt b/Documentation/gittutorial.txt index 59ef5cef1f..0e0b863105 100644 --- a/Documentation/gittutorial.txt +++ b/Documentation/gittutorial.txt @@ -322,7 +322,7 @@ initiating this "pull". If Bob's work conflicts with what Alice did since their histories forked, Alice will use her working tree and the index to resolve conflicts, and existing local changes will interfere with the conflict resolution process (Git will still perform the fetch but will -refuse to merge --- Alice will have to get rid of her local changes in +refuse to merge -- Alice will have to get rid of her local changes in some way and pull again when this happens). Alice can peek at what Bob did without merging first, using the "fetch" diff --git a/Documentation/glossary-content.txt b/Documentation/glossary-content.txt index 67c7a50b96..c077971335 100644 --- a/Documentation/glossary-content.txt +++ b/Documentation/glossary-content.txt @@ -146,8 +146,8 @@ current branch integrates with) obviously do not work, as there is no <<def_revision,revision>> and you are "merging" another <<def_branch,branch>>'s changes that happen to be a descendant of what you have. In such a case, you do not make a new <<def_merge,merge>> - <<def_commit,commit>> but instead just update to his - revision. This will happen frequently on a + <<def_commit,commit>> but instead just update your branch to point at the same + revision as the branch you are merging. This will happen frequently on a <<def_remote_tracking_branch,remote-tracking branch>> of a remote <<def_repository,repository>>. diff --git a/Documentation/lint-gitlink.perl b/Documentation/lint-gitlink.perl index 476cc30b83..b22a367844 100755 --- a/Documentation/lint-gitlink.perl +++ b/Documentation/lint-gitlink.perl @@ -1,71 +1,67 @@ #!/usr/bin/perl -use File::Find; -use Getopt::Long; +use strict; +use warnings; -my $basedir = "."; -GetOptions("basedir=s" => \$basedir) - or die("Cannot parse command line arguments\n"); +# Parse arguments, a simple state machine for input like: +# +# howto/*.txt config/*.txt --section=1 git.txt git-add.txt [...] --to-lint git-add.txt a-file.txt [...] +my %TXT; +my %SECTION; +my $section; +my $lint_these = 0; +for my $arg (@ARGV) { + if (my ($sec) = $arg =~ /^--section=(\d+)$/s) { + $section = $sec; + next; + } -my $found_errors = 0; + my ($name) = $arg =~ /^(.*?)\.txt$/s; + unless (defined $section) { + $TXT{$name} = $arg; + next; + } -sub report { - my ($where, $what, $error) = @_; - print "$where: $error: $what\n"; - $found_errors = 1; + $SECTION{$name} = $section; } -sub grab_section { - my ($page) = @_; - open my $fh, "<", "$basedir/$page.txt"; - my $firstline = <$fh>; - chomp $firstline; - close $fh; - my ($section) = ($firstline =~ /.*\((\d)\)$/); - return $section; +my $exit_code = 0; +sub report { + my ($pos, $line, $target, $msg) = @_; + substr($line, $pos) = "' <-- HERE"; + $line =~ s/^\s+//; + print "$ARGV:$.: error: $target: $msg, shown with 'HERE' below:\n"; + print "$ARGV:$.:\t'$line\n"; + $exit_code = 1; } -sub lint { - my ($file) = @_; - open my $fh, "<", $file - or return; - while (<$fh>) { - my $where = "$file:$."; - while (s/linkgit:((.*?)\[(\d)\])//) { - my ($target, $page, $section) = ($1, $2, $3); +@ARGV = sort values %TXT; +die "BUG: Nothing to process!" unless @ARGV; +while (<>) { + my $line = $_; + while ($line =~ m/linkgit:((.*?)\[(\d)\])/g) { + my $pos = pos $line; + my ($target, $page, $section) = ($1, $2, $3); - # De-AsciiDoc - $page =~ s/{litdd}/--/g; + # De-AsciiDoc + $page =~ s/{litdd}/--/g; - if ($page !~ /^git/) { - report($where, $target, "nongit link"); - next; - } - if (! -f "$basedir/$page.txt") { - report($where, $target, "no such source"); - next; - } - $real_section = grab_section($page); - if ($real_section != $section) { - report($where, $target, - "wrong section (should be $real_section)"); - next; - } + if (!exists $TXT{$page}) { + report($pos, $line, $target, "link outside of our own docs"); + next; + } + if (!exists $SECTION{$page}) { + report($pos, $line, $target, "link outside of our sectioned docs"); + next; + } + my $real_section = $SECTION{$page}; + if ($section != $SECTION{$page}) { + report($pos, $line, $target, "wrong section (should be $real_section)"); + next; } } - close $fh; -} - -sub lint_it { - lint($File::Find::name) if -f && /\.txt$/; -} - -if (!@ARGV) { - find({ wanted => \&lint_it, no_chdir => 1 }, $basedir); -} else { - for (@ARGV) { - lint($_); - } + # this resets our $. for each file + close ARGV if eof; } -exit $found_errors; +exit $exit_code; diff --git a/Documentation/lint-man-end-blurb.perl b/Documentation/lint-man-end-blurb.perl new file mode 100755 index 0000000000..d69312e5db --- /dev/null +++ b/Documentation/lint-man-end-blurb.perl @@ -0,0 +1,24 @@ +#!/usr/bin/perl + +use strict; +use warnings; + +my $exit_code = 0; +sub report { + my ($target, $msg) = @_; + print "error: $target: $msg\n"; + $exit_code = 1; +} + +local $/; +while (my $slurp = <>) { + report($ARGV, "has no 'Part of the linkgit:git[1] suite' end blurb") + unless $slurp =~ m[ + ^GIT\n + ---\n + \QPart of the linkgit:git[1] suite\E \n + \z + ]mx; +} + +exit $exit_code; diff --git a/Documentation/lint-man-section-order.perl b/Documentation/lint-man-section-order.perl new file mode 100755 index 0000000000..b05f9156dd --- /dev/null +++ b/Documentation/lint-man-section-order.perl @@ -0,0 +1,105 @@ +#!/usr/bin/perl + +use strict; +use warnings; + +my %SECTIONS; +{ + my $order = 0; + %SECTIONS = ( + 'NAME' => { + required => 1, + order => $order++, + }, + 'SYNOPSIS' => { + required => 1, + order => $order++, + }, + 'DESCRIPTION' => { + required => 1, + order => $order++, + }, + 'OPTIONS' => { + order => $order++, + required => 0, + }, + 'CONFIGURATION' => { + order => $order++, + }, + 'BUGS' => { + order => $order++, + }, + 'SEE ALSO' => { + order => $order++, + }, + 'GIT' => { + required => 1, + order => $order++, + }, + ); +} +my $SECTION_RX = do { + my ($names) = join "|", keys %SECTIONS; + qr/^($names)$/s; +}; + +my $exit_code = 0; +sub report { + my ($msg) = @_; + print "$ARGV:$.: $msg\n"; + $exit_code = 1; +} + +my $last_was_section; +my @actual_order; +while (my $line = <>) { + chomp $line; + if ($line =~ $SECTION_RX) { + push @actual_order => $line; + $last_was_section = 1; + # Have no "last" section yet, processing NAME + next if @actual_order == 1; + + my @expected_order = sort { + $SECTIONS{$a}->{order} <=> $SECTIONS{$b}->{order} + } @actual_order; + + my $expected_last = $expected_order[-2]; + my $actual_last = $actual_order[-2]; + if ($actual_last ne $expected_last) { + report("section '$line' incorrectly ordered, comes after '$actual_last'"); + } + next; + } + if ($last_was_section) { + my $last_section = $actual_order[-1]; + if (length $last_section ne length $line) { + report("dashes under '$last_section' should match its length!"); + } + if ($line !~ /^-+$/) { + report("dashes under '$last_section' should be '-' dashes!"); + } + $last_was_section = 0; + } + + if (eof) { + # We have both a hash and an array to consider, for + # convenience + my %actual_sections; + @actual_sections{@actual_order} = (); + + for my $section (sort keys %SECTIONS) { + next if !$SECTIONS{$section}->{required} or exists $actual_sections{$section}; + report("has no required '$section' section!"); + } + + # Reset per-file state + { + @actual_order = (); + # this resets our $. for each file + close ARGV; + } + } +} + +exit $exit_code; diff --git a/Documentation/merge-options.txt b/Documentation/merge-options.txt index eb0aabd396..61ec157c2f 100644 --- a/Documentation/merge-options.txt +++ b/Documentation/merge-options.txt @@ -2,6 +2,9 @@ --no-commit:: Perform the merge and commit the result. This option can be used to override --no-commit. +ifdef::git-pull[] + Only useful when merging. +endif::git-pull[] + With --no-commit perform the merge and stop just before creating a merge commit, to give the user a chance to inspect and further @@ -39,6 +42,7 @@ set to `no` at the beginning of them. to `MERGE_MSG` before being passed on to the commit machinery in the case of a merge conflict. +ifdef::git-merge[] --ff:: --no-ff:: --ff-only:: @@ -47,6 +51,22 @@ set to `no` at the beginning of them. default unless merging an annotated (and possibly signed) tag that is not stored in its natural place in the `refs/tags/` hierarchy, in which case `--no-ff` is assumed. +endif::git-merge[] +ifdef::git-pull[] +--ff-only:: + Only update to the new history if there is no divergent local + history. This is the default when no method for reconciling + divergent histories is provided (via the --rebase=* flags). + +--ff:: +--no-ff:: + When merging rather than rebasing, specifies how a merge is + handled when the merged-in history is already a descendant of + the current history. If merging is requested, `--ff` is the + default unless merging an annotated (and possibly signed) tag + that is not stored in its natural place in the `refs/tags/` + hierarchy, in which case `--no-ff` is assumed. +endif::git-pull[] + With `--ff`, when possible resolve the merge as a fast-forward (only update the branch pointer to match the merged branch; do not create a @@ -55,9 +75,11 @@ descendant of the current history), create a merge commit. + With `--no-ff`, create a merge commit in all cases, even when the merge could instead be resolved as a fast-forward. +ifdef::git-merge[] + With `--ff-only`, resolve the merge as a fast-forward when possible. When not possible, refuse to merge and exit with a non-zero status. +endif::git-merge[] -S[<keyid>]:: --gpg-sign[=<keyid>]:: @@ -73,6 +95,9 @@ When not possible, refuse to merge and exit with a non-zero status. In addition to branch names, populate the log message with one-line descriptions from at most <n> actual commits that are being merged. See also linkgit:git-fmt-merge-msg[1]. +ifdef::git-pull[] + Only useful when merging. +endif::git-pull[] + With --no-log do not list one-line descriptions from the actual commits being merged. @@ -102,18 +127,25 @@ With --no-squash perform the merge and commit the result. This option can be used to override --squash. + With --squash, --commit is not allowed, and will fail. +ifdef::git-pull[] ++ +Only useful when merging. +endif::git-pull[] --no-verify:: This option bypasses the pre-merge and commit-msg hooks. See also linkgit:githooks[5]. +ifdef::git-pull[] + Only useful when merging. +endif::git-pull[] -s <strategy>:: --strategy=<strategy>:: Use the given merge strategy; can be supplied more than once to specify them in the order they should be tried. If there is no `-s` option, a built-in list of strategies - is used instead ('git merge-recursive' when merging a single - head, 'git merge-octopus' otherwise). + is used instead (`ort` when merging a single head, + `octopus` otherwise). -X <option>:: --strategy-option=<option>:: @@ -127,6 +159,10 @@ With --squash, --commit is not allowed, and will fail. default trust model, this means the signing key has been signed by a trusted key. If the tip commit of the side branch is not signed with a valid key, the merge is aborted. +ifdef::git-pull[] ++ +Only useful when merging. +endif::git-pull[] --summary:: --no-summary:: @@ -154,7 +190,8 @@ endif::git-pull[] --autostash:: --no-autostash:: Automatically create a temporary stash entry before the operation - begins, and apply it after the operation ends. This means + begins, record it in the special ref `MERGE_AUTOSTASH` + and apply it after the operation ends. This means that you can run the operation on a dirty worktree. However, use with care: the final stash application after a successful merge might result in non-trivial conflicts. @@ -166,3 +203,7 @@ endif::git-pull[] projects that started their lives independently. As that is a very rare occasion, no configuration variable to enable this by default exists and will not be added. +ifdef::git-pull[] ++ +Only useful when merging. +endif::git-pull[] diff --git a/Documentation/merge-strategies.txt b/Documentation/merge-strategies.txt index 2912de706b..5fc54ec060 100644 --- a/Documentation/merge-strategies.txt +++ b/Documentation/merge-strategies.txt @@ -6,28 +6,23 @@ backend 'merge strategies' to be chosen with `-s` option. Some strategies can also take their own options, which can be passed by giving `-X<option>` arguments to `git merge` and/or `git pull`. -resolve:: - This can only resolve two heads (i.e. the current branch - and another branch you pulled from) using a 3-way merge - algorithm. It tries to carefully detect criss-cross - merge ambiguities and is considered generally safe and - fast. - -recursive:: - This can only resolve two heads using a 3-way merge - algorithm. When there is more than one common - ancestor that can be used for 3-way merge, it creates a - merged tree of the common ancestors and uses that as - the reference tree for the 3-way merge. This has been - reported to result in fewer merge conflicts without - causing mismerges by tests done on actual merge commits - taken from Linux 2.6 kernel development history. - Additionally this can detect and handle merges involving - renames, but currently cannot make use of detected - copies. This is the default merge strategy when pulling - or merging one branch. +ort:: + This is the default merge strategy when pulling or merging one + branch. This strategy can only resolve two heads using a + 3-way merge algorithm. When there is more than one common + ancestor that can be used for 3-way merge, it creates a merged + tree of the common ancestors and uses that as the reference + tree for the 3-way merge. This has been reported to result in + fewer merge conflicts without causing mismerges by tests done + on actual merge commits taken from Linux 2.6 kernel + development history. Additionally this strategy can detect + and handle merges involving renames. It does not make use of + detected copies. The name for this algorithm is an acronym + ("Ostensibly Recursive's Twin") and came from the fact that it + was written as a replacement for the previous default + algorithm, `recursive`. + -The 'recursive' strategy can take the following options: +The 'ort' strategy can take the following options: ours;; This option forces conflicting hunks to be auto-resolved cleanly by @@ -43,19 +38,6 @@ theirs;; This is the opposite of 'ours'; note that, unlike 'ours', there is no 'theirs' merge strategy to confuse this merge option with. -patience;; - With this option, 'merge-recursive' spends a little extra time - to avoid mismerges that sometimes occur due to unimportant - matching lines (e.g., braces from distinct functions). Use - this when the branches to be merged have diverged wildly. - See also linkgit:git-diff[1] `--patience`. - -diff-algorithm=[patience|minimal|histogram|myers];; - Tells 'merge-recursive' to use a different diff algorithm, which - can help avoid mismerges that occur due to unimportant matching - lines (such as braces from distinct functions). See also - linkgit:git-diff[1] `--diff-algorithm`. - ignore-space-change;; ignore-all-space;; ignore-space-at-eol;; @@ -84,11 +66,6 @@ no-renormalize;; Disables the `renormalize` option. This overrides the `merge.renormalize` configuration variable. -no-renames;; - Turn off rename detection. This overrides the `merge.renames` - configuration variable. - See also linkgit:git-diff[1] `--no-renames`. - find-renames[=<n>];; Turn on rename detection, optionally setting the similarity threshold. This is the default. This overrides the @@ -105,6 +82,46 @@ subtree[=<path>];; is prefixed (or stripped from the beginning) to make the shape of two trees to match. +recursive:: + This can only resolve two heads using a 3-way merge + algorithm. When there is more than one common + ancestor that can be used for 3-way merge, it creates a + merged tree of the common ancestors and uses that as + the reference tree for the 3-way merge. This has been + reported to result in fewer merge conflicts without + causing mismerges by tests done on actual merge commits + taken from Linux 2.6 kernel development history. + Additionally this can detect and handle merges involving + renames. It does not make use of detected copies. This was + the default strategy for resolving two heads from Git v0.99.9k + until v2.33.0. ++ +The 'recursive' strategy takes the same options as 'ort'. However, +there are three additional options that 'ort' ignores (not documented +above) that are potentially useful with the 'recursive' strategy: + +patience;; + Deprecated synonym for `diff-algorithm=patience`. + +diff-algorithm=[patience|minimal|histogram|myers];; + Use a different diff algorithm while merging, which can help + avoid mismerges that occur due to unimportant matching lines + (such as braces from distinct functions). See also + linkgit:git-diff[1] `--diff-algorithm`. Note that `ort` + specifically uses `diff-algorithm=histogram`, while `recursive` + defaults to the `diff.algorithm` config setting. + +no-renames;; + Turn off rename detection. This overrides the `merge.renames` + configuration variable. + See also linkgit:git-diff[1] `--no-renames`. + +resolve:: + This can only resolve two heads (i.e. the current branch + and another branch you pulled from) using a 3-way merge + algorithm. It tries to carefully detect criss-cross + merge ambiguities. It does not handle renames. + octopus:: This resolves cases with more than two heads, but refuses to do a complex merge that needs manual resolution. It is @@ -121,13 +138,13 @@ ours:: the 'recursive' merge strategy. subtree:: - This is a modified recursive strategy. When merging trees A and + This is a modified `ort` strategy. When merging trees A and B, if B corresponds to a subtree of A, B is first adjusted to match the tree structure of A, instead of reading the trees at the same level. This adjustment is also done to the common ancestor tree. -With the strategies that use 3-way merge (including the default, 'recursive'), +With the strategies that use 3-way merge (including the default, 'ort'), if a change is made on both branches, but later reverted on one of the branches, that change will be present in the merged result; some people find this behavior confusing. It occurs because only the heads and the merge base diff --git a/Documentation/pretty-formats.txt b/Documentation/pretty-formats.txt index 45133066e4..ef6bd420ae 100644 --- a/Documentation/pretty-formats.txt +++ b/Documentation/pretty-formats.txt @@ -190,6 +190,8 @@ The placeholders are: '%ai':: author date, ISO 8601-like format '%aI':: author date, strict ISO 8601 format '%as':: author date, short format (`YYYY-MM-DD`) +'%ah':: author date, human style (like the `--date=human` option of + linkgit:git-rev-list[1]) '%cn':: committer name '%cN':: committer name (respecting .mailmap, see linkgit:git-shortlog[1] or linkgit:git-blame[1]) @@ -206,6 +208,8 @@ The placeholders are: '%ci':: committer date, ISO 8601-like format '%cI':: committer date, strict ISO 8601 format '%cs':: committer date, short format (`YYYY-MM-DD`) +'%ch':: committer date, human style (like the `--date=human` option of + linkgit:git-rev-list[1]) '%d':: ref names, like the --decorate option of linkgit:git-log[1] '%D':: ref names without the " (", ")" wrapping. '%(describe[:options])':: human-readable name, like @@ -267,7 +271,7 @@ endif::git-rev-list[] `trailers` string may be followed by a colon and zero or more comma-separated options. If any option is provided multiple times the - last occurance wins. + last occurrence wins. + The boolean options accept an optional value `[=<BOOL>]`. The values `true`, `false`, `on`, `off` etc. are all accepted. See the "boolean" diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt index b1c8f86c6e..b7bd27e171 100644 --- a/Documentation/rev-list-options.txt +++ b/Documentation/rev-list-options.txt @@ -892,9 +892,12 @@ or units. n may be zero. The suffixes k, m, and g can be used to name units in KiB, MiB, or GiB. For example, 'blob:limit=1k' is the same as 'blob:limit=1024'. + +The form '--filter=object:type=(tag|commit|tree|blob)' omits all objects +which are not of the requested type. ++ The form '--filter=sparse:oid=<blob-ish>' uses a sparse-checkout specification contained in the blob (or blob-expression) '<blob-ish>' -to omit blobs that would not be not required for a sparse checkout on +to omit blobs that would not be required for a sparse checkout on the requested refs. + The form '--filter=tree:<depth>' omits all blobs and trees whose depth @@ -930,6 +933,11 @@ equivalent. --no-filter:: Turn off any previous `--filter=` argument. +--filter-provided-objects:: + Filter the list of explicitly provided objects, which would otherwise + always be printed even if they did not match any of the filters. Only + useful with `--filter=`. + --filter-print-omitted:: Only useful with `--filter=`; prints a list of the objects omitted by the filter. Object IDs are prefixed with a ``~'' character. @@ -960,6 +968,11 @@ list of the missing objects. Object IDs are prefixed with a ``?'' character. objects. endif::git-rev-list[] +--unsorted-input:: + Show commits in the order they were given on the command line instead + of sorting them in reverse chronological order by commit time. Cannot + be combined with `--no-walk` or `--no-walk=sorted`. + --no-walk[=(sorted|unsorted)]:: Only show the given commits, but do not traverse their ancestors. This has no effect if a range is specified. If the argument @@ -967,7 +980,8 @@ endif::git-rev-list[] given on the command line. Otherwise (if `sorted` or no argument was given), the commits are shown in reverse chronological order by commit time. - Cannot be combined with `--graph`. + Cannot be combined with `--graph`. Cannot be combined with + `--unsorted-input` if `sorted` or no argument was given. --do-walk:: Overrides a previous `--no-walk`. @@ -1056,6 +1070,14 @@ ifdef::git-rev-list[] --header:: Print the contents of the commit in raw-format; each record is separated with a NUL character. + +--no-commit-header:: + Suppress the header line containing "commit" and the object ID printed before + the specified format. This has no effect on the built-in formats; only custom + formats are affected. + +--commit-header:: + Overrides a previous `--no-commit-header`. endif::git-rev-list[] --parents:: diff --git a/Documentation/revisions.txt b/Documentation/revisions.txt index d9169c062e..f5f17b65a1 100644 --- a/Documentation/revisions.txt +++ b/Documentation/revisions.txt @@ -260,6 +260,9 @@ any of the given commits. A commit's reachable set is the commit itself and the commits in its ancestry chain. +There are several notations to specify a set of connected commits +(called a "revision range"), illustrated below. + Commit Exclusions ~~~~~~~~~~~~~~~~~ @@ -294,6 +297,26 @@ is a shorthand for 'HEAD..origin' and asks "What did the origin do since I forked from them?" Note that '..' would mean 'HEAD..HEAD' which is an empty range that is both reachable and unreachable from HEAD. +Commands that are specifically designed to take two distinct ranges +(e.g. "git range-diff R1 R2" to compare two ranges) do exist, but +they are exceptions. Unless otherwise noted, all "git" commands +that operate on a set of commits work on a single revision range. +In other words, writing two "two-dot range notation" next to each +other, e.g. + + $ git log A..B C..D + +does *not* specify two revision ranges for most commands. Instead +it will name a single connected set of commits, i.e. those that are +reachable from either B or D but are reachable from neither A or C. +In a linear history like this: + + ---A---B---o---o---C---D + +because A and B are reachable from C, the revision range specified +by these two dotted ranges is a single commit D. + + Other <rev>{caret} Parent Shorthand Notations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Three other shorthands exist, particularly useful for merge commits, diff --git a/Documentation/technical/api-error-handling.txt b/Documentation/technical/api-error-handling.txt index ceeedd485c..8be4f4d0d6 100644 --- a/Documentation/technical/api-error-handling.txt +++ b/Documentation/technical/api-error-handling.txt @@ -1,8 +1,11 @@ Error reporting in git ====================== -`die`, `usage`, `error`, and `warning` report errors of various -kinds. +`BUG`, `die`, `usage`, `error`, and `warning` report errors of +various kinds. + +- `BUG` is for failed internal assertions that should never happen, + i.e. a bug in git itself. - `die` is for fatal application errors. It prints a message to the user and exits with status 128. @@ -20,6 +23,9 @@ kinds. without running into too many problems. Like `error`, it returns -1 after reporting the situation to the caller. +These reports will be logged via the trace2 facility. See the "error" +event in link:api-trace2.txt[trace2 API]. + Customizable error handlers --------------------------- diff --git a/Documentation/technical/api-trace2.txt b/Documentation/technical/api-trace2.txt index c65ffafc48..b9f3198fbe 100644 --- a/Documentation/technical/api-trace2.txt +++ b/Documentation/technical/api-trace2.txt @@ -396,14 +396,14 @@ only present on the "start" and "atexit" events. } ------------ -`"discard"`:: +`"too_many_files"`:: This event is written to the git-trace2-discard sentinel file if there are too many files in the target trace directory (see the trace2.maxFiles config option). + ------------ { - "event":"discard", + "event":"too_many_files", ... } ------------ @@ -465,7 +465,7 @@ completed.) ------------ `"error"`:: - This event is emitted when one of the `error()`, `die()`, + This event is emitted when one of the `BUG()`, `error()`, `die()`, `warning()`, or `usage()` functions are called. + ------------ @@ -493,6 +493,20 @@ about specific error arguments. } ------------ +`"cmd_ancestry"`:: + This event contains the text command name for the parent (and earlier + generations of parents) of the current process, in an array ordered from + nearest parent to furthest great-grandparent. It may not be implemented + on all platforms. ++ +------------ +{ + "event":"cmd_ancestry", + ... + "ancestry":["bash","tmux: server","systemd"] +} +------------ + `"cmd_name"`:: This event contains the command name for this git process and the hierarchy of commands from parent git processes. diff --git a/Documentation/technical/directory-rename-detection.txt b/Documentation/technical/directory-rename-detection.txt index 49b83ef3cc..029ee2cedc 100644 --- a/Documentation/technical/directory-rename-detection.txt +++ b/Documentation/technical/directory-rename-detection.txt @@ -2,9 +2,9 @@ Directory rename detection ========================== Rename detection logic in diffcore-rename that checks for renames of -individual files is aggregated and analyzed in merge-recursive for cases -where combinations of renames indicate that a full directory has been -renamed. +individual files is also aggregated there and then analyzed in either +merge-ort or merge-recursive for cases where combinations of renames +indicate that a full directory has been renamed. Scope of abilities ------------------ @@ -88,9 +88,11 @@ directory rename detection support in: Folks have requested in the past that `git diff` detect directory renames and somehow simplify its output. It is not clear whether this would be desirable or how the output should be simplified, so this was - simply not implemented. Further, to implement this, directory rename - detection logic would need to move from merge-recursive to - diffcore-rename. + simply not implemented. Also, while diffcore-rename has most of the + logic for detecting directory renames, some of the logic is still found + within merge-ort and merge-recursive. Fully supporting directory + rename detection in diffs would require copying or moving the remaining + bits of logic to the diff machinery. * am diff --git a/Documentation/technical/hash-function-transition.txt b/Documentation/technical/hash-function-transition.txt index 7c1630bf83..260224b033 100644 --- a/Documentation/technical/hash-function-transition.txt +++ b/Documentation/technical/hash-function-transition.txt @@ -599,7 +599,7 @@ supports four different modes of operation: convert any object names written to output to SHA-1, but store objects using SHA-256. This allows users to test the code with no visible behavior change except for performance. This allows - allows running even tests that assume the SHA-1 hash function, to + running even tests that assume the SHA-1 hash function, to sanity-check the behavior of the new mode. 2. ("early transition") Allow both SHA-1 and SHA-256 object names in diff --git a/Documentation/technical/index-format.txt b/Documentation/technical/index-format.txt index d363a71c37..65da0daaa5 100644 --- a/Documentation/technical/index-format.txt +++ b/Documentation/technical/index-format.txt @@ -44,6 +44,13 @@ Git index format localization, no special casing of directory separator '/'). Entries with the same name are sorted by their stage field. + An index entry typically represents a file. However, if sparse-checkout + is enabled in cone mode (`core.sparseCheckoutCone` is enabled) and the + `extensions.sparseIndex` extension is enabled, then the index may + contain entries for directories outside of the sparse-checkout definition. + These entries have mode `040000`, include the `SKIP_WORKTREE` bit, and + the path ends in a directory separator. + 32-bit ctime seconds, the last time a file's metadata changed this is stat(2) data @@ -385,3 +392,15 @@ The remaining data of each directory block is grouped by type: in this block of entries. - 32-bit count of cache entries in this block + +== Sparse Directory Entries + + When using sparse-checkout in cone mode, some entire directories within + the index can be summarized by pointing to a tree object instead of the + entire expanded list of paths within that tree. An index containing such + entries is a "sparse index". Index format versions 4 and less were not + implemented with such entries in mind. Thus, for these versions, an + index containing sparse directory entries will include this extension + with signature { 's', 'd', 'i', 'r' }. Like the split-index extension, + tools should avoid interacting with a sparse index unless they understand + this extension. diff --git a/Documentation/technical/packfile-uri.txt b/Documentation/technical/packfile-uri.txt index f7eabc6c76..1eb525fe76 100644 --- a/Documentation/technical/packfile-uri.txt +++ b/Documentation/technical/packfile-uri.txt @@ -35,13 +35,14 @@ include some sort of non-trivial implementation in the Minimum Viable Product, at least so that we can test the client. This is the implementation: a feature, marked experimental, that allows the -server to be configured by one or more `uploadpack.blobPackfileUri=<sha1> -<uri>` entries. Whenever the list of objects to be sent is assembled, all such -blobs are excluded, replaced with URIs. As noted in "Future work" below, the -server can evolve in the future to support excluding other objects (or other -implementations of servers could be made that support excluding other objects) -without needing a protocol change, so clients should not expect that packfiles -downloaded in this way only contain single blobs. +server to be configured by one or more `uploadpack.blobPackfileUri= +<object-hash> <pack-hash> <uri>` entries. Whenever the list of objects to be +sent is assembled, all such blobs are excluded, replaced with URIs. As noted +in "Future work" below, the server can evolve in the future to support +excluding other objects (or other implementations of servers could be made +that support excluding other objects) without needing a protocol change, so +clients should not expect that packfiles downloaded in this way only contain +single blobs. Client design ------------- diff --git a/Documentation/technical/parallel-checkout.txt b/Documentation/technical/parallel-checkout.txt new file mode 100644 index 0000000000..e790258a1a --- /dev/null +++ b/Documentation/technical/parallel-checkout.txt @@ -0,0 +1,270 @@ +Parallel Checkout Design Notes +============================== + +The "Parallel Checkout" feature attempts to use multiple processes to +parallelize the work of uncompressing the blobs, applying in-core +filters, and writing the resulting contents to the working tree during a +checkout operation. It can be used by all checkout-related commands, +such as `clone`, `checkout`, `reset`, `sparse-checkout`, and others. + +These commands share the following basic structure: + +* Step 1: Read the current index file into memory. + +* Step 2: Modify the in-memory index based upon the command, and + temporarily mark all cache entries that need to be updated. + +* Step 3: Populate the working tree to match the new candidate index. + This includes iterating over all of the to-be-updated cache entries + and delete, create, or overwrite the associated files in the working + tree. + +* Step 4: Write the new index to disk. + +Step 3 is the focus of the "parallel checkout" effort described here. + +Sequential Implementation +------------------------- + +For the purposes of discussion here, the current sequential +implementation of Step 3 is divided in 3 parts, each one implemented in +its own function: + +* Step 3a: `unpack-trees.c:check_updates()` contains a series of + sequential loops iterating over the `cache_entry`'s array. The main + loop in this function calls the Step 3b function for each of the + to-be-updated entries. + +* Step 3b: `entry.c:checkout_entry()` examines the existing working tree + for file conflicts, collisions, and unsaved changes. It removes files + and creates leading directories as necessary. It calls the Step 3c + function for each entry to be written. + +* Step 3c: `entry.c:write_entry()` loads the blob into memory, smudges + it if necessary, creates the file in the working tree, writes the + smudged contents, calls `fstat()` or `lstat()`, and updates the + associated `cache_entry` struct with the stat information gathered. + +It wouldn't be safe to perform Step 3b in parallel, as there could be +race conditions between file creations and removals. Instead, the +parallel checkout framework lets the sequential code handle Step 3b, +and uses parallel workers to replace the sequential +`entry.c:write_entry()` calls from Step 3c. + +Rejected Multi-Threaded Solution +-------------------------------- + +The most "straightforward" implementation would be to spread the set of +to-be-updated cache entries across multiple threads. But due to the +thread-unsafe functions in the ODB code, we would have to use locks to +coordinate the parallel operation. An early prototype of this solution +showed that the multi-threaded checkout would bring performance +improvements over the sequential code, but there was still too much lock +contention. A `perf` profiling indicated that around 20% of the runtime +during a local Linux clone (on an SSD) was spent in locking functions. +For this reason this approach was rejected in favor of using multiple +child processes, which led to a better performance. + +Multi-Process Solution +---------------------- + +Parallel checkout alters the aforementioned Step 3 to use multiple +`checkout--worker` background processes to distribute the work. The +long-running worker processes are controlled by the foreground Git +command using the existing run-command API. + +Overview +~~~~~~~~ + +Step 3b is only slightly altered; for each entry to be checked out, the +main process performs the following steps: + +* M1: Check whether there is any untracked or unclean file in the + working tree which would be overwritten by this entry, and decide + whether to proceed (removing the file(s)) or not. + +* M2: Create the leading directories. + +* M3: Load the conversion attributes for the entry's path. + +* M4: Check, based on the entry's type and conversion attributes, + whether the entry is eligible for parallel checkout (more on this + later). If it is eligible, enqueue the entry and the loaded + attributes to later write the entry in parallel. If not, write the + entry right away, using the default sequential code. + +Note: we save the conversion attributes associated with each entry +because the workers don't have access to the main process' index state, +so they can't load the attributes by themselves (and the attributes are +needed to properly smudge the entry). Additionally, this has a positive +impact on performance as (1) we don't need to load the attributes twice +and (2) the attributes machinery is optimized to handle paths in +sequential order. + +After all entries have passed through the above steps, the main process +checks if the number of enqueued entries is sufficient to spread among +the workers. If not, it just writes them sequentially. Otherwise, it +spawns the workers and distributes the queued entries uniformly in +continuous chunks. This aims to minimize the chances of two workers +writing to the same directory simultaneously, which could increase lock +contention in the kernel. + +Then, for each assigned item, each worker: + +* W1: Checks if there is any non-directory file in the leading part of + the entry's path or if there already exists a file at the entry' path. + If so, mark the entry with `PC_ITEM_COLLIDED` and skip it (more on + this later). + +* W2: Creates the file (with O_CREAT and O_EXCL). + +* W3: Loads the blob into memory (inflating and delta reconstructing + it). + +* W4: Applies any required in-process filter, like end-of-line + conversion and re-encoding. + +* W5: Writes the result to the file descriptor opened at W2. + +* W6: Calls `fstat()` or lstat()` on the just-written path, and sends + the result back to the main process, together with the end status of + the operation and the item's identification number. + +Note that, when possible, steps W3 to W5 are delegated to the streaming +machinery, removing the need to keep the entire blob in memory. + +If the worker fails to read the blob or to write it to the working tree, +it removes the created file to avoid leaving empty files behind. This is +the *only* time a worker is allowed to remove a file. + +As mentioned earlier, it is the responsibility of the main process to +remove any file that blocks the checkout operation (or abort if the +removal(s) would cause data loss and the user didn't ask to `--force`). +This is crucial to avoid race conditions and also to properly detect +path collisions at Step W1. + +After the workers finish writing the items and sending back the required +information, the main process handles the results in two steps: + +- First, it updates the in-memory index with the `lstat()` information + sent by the workers. (This must be done first as this information + might me required in the following step.) + +- Then it writes the items which collided on disk (i.e. items marked + with `PC_ITEM_COLLIDED`). More on this below. + +Path Collisions +--------------- + +Path collisions happen when two different paths correspond to the same +entry in the file system. E.g. the paths 'a' and 'A' would collide in a +case-insensitive file system. + +The sequential checkout deals with collisions in the same way that it +deals with files that were already present in the working tree before +checkout. Basically, it checks if the path that it wants to write +already exists on disk, makes sure the existing file doesn't have +unsaved data, and then overwrites it. (To be more pedantic: it deletes +the existing file and creates the new one.) So, if there are multiple +colliding files to be checked out, the sequential code will write each +one of them but only the last will actually survive on disk. + +Parallel checkout aims to reproduce the same behavior. However, we +cannot let the workers racily write to the same file on disk. Instead, +the workers detect when the entry that they want to check out would +collide with an existing file, and mark it with `PC_ITEM_COLLIDED`. +Later, the main process can sequentially feed these entries back to +`checkout_entry()` without the risk of race conditions. On clone, this +also has the effect of marking the colliding entries to later emit a +warning for the user, like the classic sequential checkout does. + +The workers are able to detect both collisions among the entries being +concurrently written and collisions between a parallel-eligible entry +and an ineligible entry. The general idea for collision detection is +quite straightforward: for each parallel-eligible entry, the main +process must remove all files that prevent this entry from being written +(before enqueueing it). This includes any non-directory file in the +leading path of the entry. Later, when a worker gets assigned the entry, +it looks again for the non-directories files and for an already existing +file at the entry's path. If any of these checks finds something, the +worker knows that there was a path collision. + +Because parallel checkout can distinguish path collisions from the case +where the file was already present in the working tree before checkout, +we could alternatively choose to skip the checkout of colliding entries. +However, each entry that doesn't get written would have NULL `lstat()` +fields on the index. This could cause performance penalties for +subsequent commands that need to refresh the index, as they would have +to go to the file system to see if the entry is dirty. Thus, if we have +N entries in a colliding group and we decide to write and `lstat()` only +one of them, every subsequent `git-status` will have to read, convert, +and hash the written file N - 1 times. By checking out all colliding +entries (like the sequential code does), we only pay the overhead once, +during checkout. + +Eligible Entries for Parallel Checkout +-------------------------------------- + +As previously mentioned, not all entries passed to `checkout_entry()` +will be considered eligible for parallel checkout. More specifically, we +exclude: + +- Symbolic links; to avoid race conditions that, in combination with + path collisions, could cause workers to write files at the wrong + place. For example, if we were to concurrently check out a symlink + 'a' -> 'b' and a regular file 'A/f' in a case-insensitive file system, + we could potentially end up writing the file 'A/f' at 'a/f', due to a + race condition. + +- Regular files that require external filters (either "one shot" filters + or long-running process filters). These filters are black-boxes to Git + and may have their own internal locking or non-concurrent assumptions. + So it might not be safe to run multiple instances in parallel. ++ +Besides, long-running filters may use the delayed checkout feature to +postpone the return of some filtered blobs. The delayed checkout queue +and the parallel checkout queue are not compatible and should remain +separate. ++ +Note: regular files that only require internal filters, like end-of-line +conversion and re-encoding, are eligible for parallel checkout. + +Ineligible entries are checked out by the classic sequential codepath +*before* spawning workers. + +Note: submodules's files are also eligible for parallel checkout (as +long as they don't fall into any of the excluding categories mentioned +above). But since each submodule is checked out in its own child +process, we don't mix the superproject's and the submodules' files in +the same parallel checkout process or queue. + +The API +------- + +The parallel checkout API was designed with the goal of minimizing +changes to the current users of the checkout machinery. This means that +they don't have to call a different function for sequential or parallel +checkout. As already mentioned, `checkout_entry()` will automatically +insert the given entry in the parallel checkout queue when this feature +is enabled and the entry is eligible; otherwise, it will just write the +entry right away, using the sequential code. In general, callers of the +parallel checkout API should look similar to this: + +---------------------------------------------- +int pc_workers, pc_threshold, err = 0; +struct checkout state; + +get_parallel_checkout_configs(&pc_workers, &pc_threshold); + +/* + * This check is not strictly required, but it + * should save some time in sequential mode. + */ +if (pc_workers > 1) + init_parallel_checkout(); + +for (each cache_entry ce to-be-updated) + err |= checkout_entry(ce, &state, NULL, NULL); + +err |= run_parallel_checkout(&state, pc_workers, pc_threshold, NULL, NULL); +---------------------------------------------- diff --git a/Documentation/technical/partial-clone.txt b/Documentation/technical/partial-clone.txt index 0780d30cac..a0dd7c66f2 100644 --- a/Documentation/technical/partial-clone.txt +++ b/Documentation/technical/partial-clone.txt @@ -242,8 +242,7 @@ remote in a specific order. repository and can satisfy all such requests. - Repack essentially treats promisor and non-promisor packfiles as 2 - distinct partitions and does not mix them. Repack currently only works - on non-promisor packfiles and loose objects. + distinct partitions and does not mix them. - Dynamic object fetching invokes fetch-pack once *for each item* because most algorithms stumble upon a missing object and need to have @@ -273,9 +272,6 @@ to use those promisor remotes in that order." The user might want to work in a triangular work flow with multiple promisor remotes that each have an incomplete view of the repository. -- Allow repack to work on promisor packfiles (while keeping them distinct - from non-promisor packfiles). - - Allow non-pathname-based filters to make use of packfile bitmaps (when present). This was just an omission during the initial implementation. diff --git a/Documentation/technical/protocol-v2.txt b/Documentation/technical/protocol-v2.txt index f4ed141774..1040d85319 100644 --- a/Documentation/technical/protocol-v2.txt +++ b/Documentation/technical/protocol-v2.txt @@ -346,6 +346,14 @@ explained below. client should download from all given URIs. Currently, the protocols supported are "http" and "https". +If the 'wait-for-done' feature is advertised, the following argument +can be included in the client's request. + + wait-for-done + Indicates to the server that it should never send "ready", but + should wait for the client to say "done" before sending the + packfile. + The response of `fetch` is broken into a number of sections separated by delimiter packets (0001), with each section beginning with its section header. Most sections are sent only when the packfile is sent. @@ -532,7 +540,7 @@ An `object-info` request takes the following arguments: Indicates to the server an object which the client wants to obtain information for. -The response of `object-info` is a list of the the requested object ids +The response of `object-info` is a list of the requested object ids and associated requested information, each separated by a single space. output = info flush-pkt diff --git a/Documentation/technical/reftable.txt b/Documentation/technical/reftable.txt index 3ef169af27..d7c3b645cf 100644 --- a/Documentation/technical/reftable.txt +++ b/Documentation/technical/reftable.txt @@ -1011,8 +1011,13 @@ reftable stack, reload `tables.list`, and delete any tables no longer mentioned in `tables.list`. Irregular program exit may still leave about unused files. In this case, a -cleanup operation can read `tables.list`, note its modification timestamp, and -delete any unreferenced `*.ref` files that are older. +cleanup operation should proceed as follows: + +* take a lock `tables.list.lock` to prevent concurrent modifications +* refresh the reftable stack, by reading `tables.list` +* for each `*.ref` file, remove it if +** it is not mentioned in `tables.list`, and +** its max update_index is not beyond the max update_index of the stack Alternatives considered diff --git a/Documentation/technical/remembering-renames.txt b/Documentation/technical/remembering-renames.txt new file mode 100644 index 0000000000..2fd5cc88e0 --- /dev/null +++ b/Documentation/technical/remembering-renames.txt @@ -0,0 +1,671 @@ +Rebases and cherry-picks involve a sequence of merges whose results are +recorded as new single-parent commits. The first parent side of those +merges represent the "upstream" side, and often include a far larger set of +changes than the second parent side. Traditionally, the renames on the +first-parent side of that sequence of merges were repeatedly re-detected +for every merge. This file explains why it is safe and effective during +rebases and cherry-picks to remember renames on the upstream side of +history as an optimization, assuming all merges are automatic and clean +(i.e. no conflicts and not interrupted for user input or editing). + +Outline: + + 0. Assumptions + + 1. How rebasing and cherry-picking work + + 2. Why the renames on MERGE_SIDE1 in any given pick are *always* a + superset of the renames on MERGE_SIDE1 for the next pick. + + 3. Why any rename on MERGE_SIDE1 in any given pick is _almost_ always also + a rename on MERGE_SIDE1 for the next pick + + 4. A detailed description of the the counter-examples to #3. + + 5. Why the special cases in #4 are still fully reasonable to use to pair + up files for three-way content merging in the merge machinery, and why + they do not affect the correctness of the merge. + + 6. Interaction with skipping of "irrelevant" renames + + 7. Additional items that need to be cached + + 8. How directory rename detection interacts with the above and why this + optimization is still safe even if merge.directoryRenames is set to + "true". + + +=== 0. Assumptions === + +There are two assumptions that will hold throughout this document: + + * The upstream side where commits are transplanted to is treated as the + first parent side when rebase/cherry-pick call the merge machinery + + * All merges are fully automatic + +and a third that will hold in sections 2-5 for simplicity, that I'll later +address in section 8: + + * No directory renames occur + + +Let me explain more about each assumption and why I include it: + + +The first assumption is merely for the purposes of making this document +clearer; the optimization implementation does not actually depend upon it. +However, the assumption does hold in all cases because it reflects the way +that both rebase and cherry-pick were implemented; and the implementation +of cherry-pick and rebase are not readily changeable for backwards +compatibility reasons (see for example the discussion of the --ours and +--theirs flag in the documentation of `git checkout`, particularly the +comments about how they behave with rebase). The optimization avoids +checking first-parent-ness, though. It checks the conditions that make the +optimization valid instead, so it would still continue working if someone +changed the parent ordering that cherry-pick and rebase use. But making +this assumption does make this document much clearer and prevents me from +having to repeat every example twice. + +If the second assumption is violated, then the optimization simply is +turned off and thus isn't relevant to consider. The second assumption can +also be stated as "there is no interruption for a user to resolve conflicts +or to just further edit or tweak files". While real rebases and +cherry-picks are often interrupted (either because it's an interactive +rebase where the user requested to stop and edit, or because there were +conflicts that the user needs to resolve), the cache of renames is not +stored on disk, and thus is thrown away as soon as the rebase or cherry +pick stops for the user to resolve the operation. + +The third assumption makes sections 2-5 simpler, and allows people to +understand the basics of why this optimization is safe and effective, and +then I can go back and address the specifics in section 8. It is probably +also worth noting that if directory renames do occur, then the default of +merge.directoryRenames being set to "conflict" means that the operation +will stop for users to resolve the conflicts and the cache will be thrown +away, and thus that there won't be an optimization to apply. So, the only +reason we need to address directory renames specifically, is that some +users will have set merge.directoryRenames to "true" to allow the merges to +continue to proceed automatically. The optimization is still safe with +this config setting, but we have to discuss a few more cases to show why; +this discussion is deferred until section 8. + + +=== 1. How rebasing and cherry-picking work === + +Consider the following setup (from the git-rebase manpage): + + A---B---C topic + / + D---E---F---G main + +After rebasing or cherry-picking topic onto main, this will appear as: + + A'--B'--C' topic + / + D---E---F---G main + +The way the commits A', B', and C' are created is through a series of +merges, where rebase or cherry-pick sequentially uses each of the three +A-B-C commits in a special merge operation. Let's label the three commits +in the merge operation as MERGE_BASE, MERGE_SIDE1, and MERGE_SIDE2. For +this picture, the three commits for each of the three merges would be: + +To create A': + MERGE_BASE: E + MERGE_SIDE1: G + MERGE_SIDE2: A + +To create B': + MERGE_BASE: A + MERGE_SIDE1: A' + MERGE_SIDE2: B + +To create C': + MERGE_BASE: B + MERGE_SIDE1: B' + MERGE_SIDE2: C + +Sometimes, folks are surprised that these three-way merges are done. It +can be useful in understanding these three-way merges to view them in a +slightly different light. For example, in creating C', you can view it as +either: + + * Apply the changes between B & C to B' + * Apply the changes between B & B' to C + +Conceptually the two statements above are the same as a three-way merge of +B, B', and C, at least the parts before you decide to record a commit. + + +=== 2. Why the renames on MERGE_SIDE1 in any given pick are always a === +=== superset of the renames on MERGE_SIDE1 for the next pick. === + +The merge machinery uses the filenames it is fed from MERGE_BASE, +MERGE_SIDE1, and MERGE_SIDE2. It will only move content to a different +filename under one of three conditions: + + * To make both pieces of a conflict available to a user during conflict + resolution (examples: directory/file conflict, add/add type conflict + such as symlink vs. regular file) + + * When MERGE_SIDE1 renames the file. + + * When MERGE_SIDE2 renames the file. + +First, let's remember what commits are involved in the first and second +picks of the cherry-pick or rebase sequence: + +To create A': + MERGE_BASE: E + MERGE_SIDE1: G + MERGE_SIDE2: A + +To create B': + MERGE_BASE: A + MERGE_SIDE1: A' + MERGE_SIDE2: B + +So, in particular, we need to show that the renames between E and G are a +superset of those between A and A'. + +A' is created by the first merge. A' will only have renames for one of the +three reasons listed above. The first case, a conflict, results in a +situation where the cache is dropped and thus this optimization doesn't +take effect, so we need not consider that case. The third case, a rename +on MERGE_SIDE2 (i.e. from G to A), will show up in A' but it also shows up +in A -- therefore when diffing A and A' that path does not show up as a +rename. The only remaining way for renames to show up in A' is for the +rename to come from MERGE_SIDE1. Therefore, all renames between A and A' +are a subset of those between E and G. Equivalently, all renames between E +and G are a superset of those between A and A'. + + +=== 3. Why any rename on MERGE_SIDE1 in any given pick is _almost_ === +=== always also a rename on MERGE_SIDE1 for the next pick. === + +Let's again look at the first two picks: + +To create A': + MERGE_BASE: E + MERGE_SIDE1: G + MERGE_SIDE2: A + +To create B': + MERGE_BASE: A + MERGE_SIDE1: A' + MERGE_SIDE2: B + +Now let's look at any given rename from MERGE_SIDE1 of the first pick, i.e. +any given rename from E to G. Let's use the filenames 'oldfile' and +'newfile' for demonstration purposes. That first pick will function as +follows; when the rename is detected, the merge machinery will do a +three-way content merge of the following: + E:oldfile + G:newfile + A:oldfile +and produce a new result: + A':newfile + +Note above that I've assumed that E->A did not rename oldfile. If that +side did rename, then we most likely have a rename/rename(1to2) conflict +that will cause the rebase or cherry-pick operation to halt and drop the +in-memory cache of renames and thus doesn't need to be considered further. +In the special case that E->A does rename the file but also renames it to +newfile, then there is no conflict from the renaming and the merge can +succeed. In this special case, the rename is not valid to cache because +the second merge will find A:newfile in the MERGE_BASE (see also the new +testcases in t6429 with "rename same file identically" in their +description). So a rename/rename(1to1) needs to be specially handled by +pruning renames from the cache and decrementing the dir_rename_counts in +the current and leading directories associated with those renames. Or, +since these are really rare, one could just take the easy way out and +disable the remembering renames optimization when a rename/rename(1to1) +happens. + +The previous paragraph handled the cases for E->A renaming oldfile, let's +continue assuming that oldfile is not renamed in A. + +As per the diagram for creating B', MERGE_SIDE1 involves the changes from A +to A'. So, we are curious whether A:oldfile and A':newfile will be viewed +as renames. Note that: + + * There will be no A':oldfile (because there could not have been a + G:oldfile as we do not do break detection in the merge machinery and + G:newfile was detected as a rename, and by the construction of the + rename above that merged cleanly, the merge machinery will ensure there + is no 'oldfile' in the result). + + * There will be no A:newfile (if there had been, we would have had a + rename/add conflict). + + * Clearly A:oldfile and A':newfile are "related" (A':newfile came from a + clean three-way content merge involving A:oldfile). + +We can also expound on the third point above, by noting that three-way +content merges can also be viewed as applying the differences between the +base and one side to the other side. Thus we can view A':newfile as +having been created by taking the changes between E:oldfile and G:newfile +(which were detected as being related, i.e. <50% changed) to A:oldfile. + +Thus A:oldfile and A':newfile are just as related as E:oldfile and +G:newfile are -- they have exactly identical differences. Since the latter +were detected as renames, A:oldfile and A':newfile should also be +detectable as renames almost always. + + +=== 4. A detailed description of the counter-examples to #3. === + +We already noted in section 3 that rename/rename(1to1) (i.e. both sides +renaming a file the same way) was one counter-example. The more +interesting bit, though, is why did we need to use the "almost" qualifier +when stating that A:oldfile and A':newfile are "almost" always detectable +as renames? + +Let's repeat an earlier point that section 3 made: + + A':newfile was created by applying the changes between E:oldfile and + G:newfile to A:oldfile. The changes between E:oldfile and G:newfile were + <50% of the size of E:oldfile. + +If those changes that were <50% of the size of E:oldfile are also <50% of +the size of A:oldfile, then A:oldfile and A':newfile will be detectable as +renames. However, if there is a dramatic size reduction between E:oldfile +and A:oldfile (but the changes between E:oldfile, G:newfile, and A:oldfile +still somehow merge cleanly), then traditional rename detection would not +detect A:oldfile and A':newfile as renames. + +Here's an example where that can happen: + * E:oldfile had 20 lines + * G:newfile added 10 new lines at the beginning of the file + * A:oldfile kept the first 3 lines of the file, and deleted all the rest +then + => A':newfile would have 13 lines, 3 of which matches those in A:oldfile. +E:oldfile -> G:newfile would be detected as a rename, but A:oldfile and +A':newfile would not be. + + +=== 5. Why the special cases in #4 are still fully reasonable to use to === +=== pair up files for three-way content merging in the merge machinery, === +=== and why they do not affect the correctness of the merge. === + +In the rename/rename(1to1) case, A:newfile and A':newfile are not renames +since they use the *same* filename. However, files with the same filename +are obviously fine to pair up for three-way content merging (the merge +machinery has never employed break detection). The interesting +counter-example case is thus not the rename/rename(1to1) case, but the case +where A did not rename oldfile. That was the case that we spent most of +the time discussing in sections 3 and 4. The remainder of this section +will be devoted to that case as well. + +So, even if A:oldfile and A':newfile aren't detectable as renames, why is +it still reasonable to pair them up for three-way content merging in the +merge machinery? There are multiple reasons: + + * As noted in sections 3 and 4, the diff between A:oldfile and A':newfile + is *exactly* the same as the diff between E:oldfile and G:newfile. The + latter pair were detected as renames, so it seems unlikely to surprise + users for us to treat A:oldfile and A':newfile as renames. + + * In fact, "oldfile" and "newfile" were at one point detected as renames + due to how they were constructed in the E..G chain. And we used that + information once already in this rebase/cherry-pick. I think users + would be unlikely to be surprised at us continuing to treat the files + as renames and would quickly understand why we had done so. + + * Marking or declaring files as renames is *not* the end goal for merges. + Merges use renames to determine which files make sense to be paired up + for three-way content merges. + + * A:oldfile and A':newfile were _already_ paired up in a three-way + content merge; that is how A':newfile was created. In fact, that + three-way content merge was clean. So using them again in a later + three-way content merge seems very reasonable. + +However, the above is focusing on the common scenarios. Let's try to look +at all possible unusual scenarios and compare without the optimization to +with the optimization. Consider the following theoretical cases; we will +then dive into each to determine which of them are possible, +and if so, what they mean: + + 1. Without the optimization, the second merge results in a conflict. + With the optimization, the second merge also results in a conflict. + Questions: Are the conflicts confusingly different? Better in one case? + + 2. Without the optimization, the second merge results in NO conflict. + With the optimization, the second merge also results in NO conflict. + Questions: Are the merges the same? + + 3. Without the optimization, the second merge results in a conflict. + With the optimization, the second merge results in NO conflict. + Questions: Possible? Bug, bugfix, or something else? + + 4. Without the optimization, the second merge results in NO conflict. + With the optimization, the second merge results in a conflict. + Questions: Possible? Bug, bugfix, or something else? + +I'll consider all four cases, but out of order. + +The fourth case is impossible. For the code without the remembering +renames optimization to not get a conflict, B:oldfile would need to exactly +match A:oldfile -- if it doesn't, there would be a modify/delete conflict. +If A:oldfile matches B:oldfile exactly, then a three-way content merge +between A:oldfile, A':newfile, and B:oldfile would have no conflict and +just give us the version of newfile from A' as the result. + +From the same logic as the above paragraph, the second case would indeed +result in identical merges. When A:oldfile exactly matches B:oldfile, an +undetected rename would say, "Oh, I see one side didn't modify 'oldfile' +and the other side deleted it. I'll delete it. And I see you have this +brand new file named 'newfile' in A', so I'll keep it." That gives the +same results as three-way content merging A:oldfile, A':newfile, and +B:oldfile -- a removal of oldfile with the version of newfile from A' +showing up in the result. + +The third case is interesting. It means that A:oldfile and A':newfile were +not just similar enough, but that the changes between them did not conflict +with the changes between A:oldfile and B:oldfile. This would validate our +hunch that the files were similar enough to be used in a three-way content +merge, and thus seems entirely correct for us to have used them that way. +(Sidenote: One particular example here may be enlightening. Let's say that +B was an immediate revert of A. B clearly would have been a clean revert +of A, since A was B's immediate parent. One would assume that if you can +pick a commit, you should also be able to cherry-pick its immediate revert. +However, this is one of those funny corner cases; without this +optimization, we just successfully picked a commit cleanly, but we are +unable to cherry-pick its immediate revert due to the size differences +between E:oldfile and A:oldfile.) + +That leaves only the first case to consider -- when we get conflicts both +with or without the optimization. Without the optimization, we'll have a +modify/delete conflict, where both A':newfile and B:oldfile are left in the +tree for the user to deal with and no hints about the potential similarity +between the two. With the optimization, we'll have a three-way content +merged A:oldfile, A':newfile, and B:oldfile with conflict markers +suggesting we thought the files were related but giving the user the chance +to resolve. As noted above, I don't think users will find us treating +'oldfile' and 'newfile' as related as a surprise since they were between E +and G. In any event, though, this case shouldn't be concerning since we +hit a conflict in both cases, told the user what we know, and asked them to +resolve it. + +So, in summary, case 4 is impossible, case 2 yields the same behavior, and +cases 1 and 3 seem to provide as good or better behavior with the +optimization than without. + + +=== 6. Interaction with skipping of "irrelevant" renames === + +Previous optimizations involved skipping rename detection for paths +considered to be "irrelevant". See for example the following commits: + + * 32a56dfb99 ("merge-ort: precompute subset of sources for which we + need rename detection", 2021-03-11) + * 2fd9eda462 ("merge-ort: precompute whether directory rename + detection is needed", 2021-03-11) + * 9bd342137e ("diffcore-rename: determine which relevant_sources are + no longer relevant", 2021-03-13) + +Relevance is always determined by what the _other_ side of history has +done, in terms of modifing a file that our side renamed, or adding a +file to a directory which our side renamed. This means that a path +that is "irrelevant" when picking the first commit of a series in a +rebase or cherry-pick, may suddenly become "relevant" when picking the +next commit. + +The upshot of this is that we can only cache rename detection results +for relevant paths, and need to re-check relevance in subsequent +commits. If those subsequent commits have additional paths that are +relevant for rename detection, then we will need to redo rename +detection -- though we can limit it to the paths for which we have not +already detected renames. + + +=== 7. Additional items that need to be cached === + +It turns out we have to cache more than just renames; we also cache: + + A) non-renames (i.e. unpaired deletes) + B) counts of renames within directories + C) sources that were marked as RELEVANT_LOCATION, but which were + downgraded to RELEVANT_NO_MORE + D) the toplevel trees involved in the merge + +These are all stored in struct rename_info, and respectively appear in + * cached_pairs (along side actual renames, just with a value of NULL) + * dir_rename_counts + * cached_irrelevant + * merge_trees + +The reason for (A) comes from the irrelevant renames skipping +optimization discussed in section 6. The fact that irrelevant renames +are skipped means we only get a subset of the potential renames +detected and subsequent commits may need to run rename detection on +the upstream side on a subset of the remaining renames (to get the +renames that are relevant for that later commit). Since unpaired +deletes are involved in rename detection too, we don't want to +repeatedly check that those paths remain unpaired on the upstream side +with every commit we are transplanting. + +The reason for (B) is that diffcore_rename_extended() is what +generates the counts of renames by directory which is needed in +directory rename detection, and if we don't run +diffcore_rename_extended() again then we need to have the output from +it, including dir_rename_counts, from the previous run. + +The reason for (C) is that merge-ort's tree traversal will again think +those paths are relevant (marking them as RELEVANT_LOCATION), but the +fact that they were downgraded to RELEVANT_NO_MORE means that +dir_rename_counts already has the information we need for directory +rename detection. (A path which becomes RELEVANT_CONTENT in a +subsequent commit will be removed from cached_irrelevant.) + +The reason for (D) is that is how we determine whether the remember +renames optimization can be used. In particular, remembering that our +sequence of merges looks like: + + Merge 1: + MERGE_BASE: E + MERGE_SIDE1: G + MERGE_SIDE2: A + => Creates A' + + Merge 2: + MERGE_BASE: A + MERGE_SIDE1: A' + MERGE_SIDE2: B + => Creates B' + +It is the fact that the trees A and A' appear both in Merge 1 and in +Merge 2, with A as a parent of A' that allows this optimization. So +we store the trees to compare with what we are asked to merge next +time. + + +=== 8. How directory rename detection interacts with the above and === +=== why this optimization is still safe even if === +=== merge.directoryRenames is set to "true". === + +As noted in the assumptions section: + + """ + ...if directory renames do occur, then the default of + merge.directoryRenames being set to "conflict" means that the operation + will stop for users to resolve the conflicts and the cache will be + thrown away, and thus that there won't be an optimization to apply. + So, the only reason we need to address directory renames specifically, + is that some users will have set merge.directoryRenames to "true" to + allow the merges to continue to proceed automatically. + """ + +Let's remember that we need to look at how any given pick affects the next +one. So let's again use the first two picks from the diagram in section +one: + + First pick does this three-way merge: + MERGE_BASE: E + MERGE_SIDE1: G + MERGE_SIDE2: A + => creates A' + + Second pick does this three-way merge: + MERGE_BASE: A + MERGE_SIDE1: A' + MERGE_SIDE2: B + => creates B' + +Now, directory rename detection exists so that if one side of history +renames a directory, and the other side adds a new file to the old +directory, then the merge (with merge.directoryRenames=true) can move the +file into the new directory. There are two qualitatively different ways to +add a new file to an old directory: create a new file, or rename a file +into that directory. Also, directory renames can be done on either side of +history, so there are four cases to consider: + + * MERGE_SIDE1 renames old dir, MERGE_SIDE2 adds new file to old dir + * MERGE_SIDE1 renames old dir, MERGE_SIDE2 renames file into old dir + * MERGE_SIDE1 adds new file to old dir, MERGE_SIDE2 renames old dir + * MERGE_SIDE1 renames file into old dir, MERGE_SIDE2 renames old dir + +One last note before we consider these four cases: There are some +important properties about how we implement this optimization with +respect to directory rename detection that we need to bear in mind +while considering all of these cases: + + * rename caching occurs *after* applying directory renames + + * a rename created by directory rename detection is recorded for the side + of history that did the directory rename. + + * dir_rename_counts, the nested map of + {oldname => {newname => count}}, + is cached between runs as well. This basically means that directory + rename detection is also cached, though only on the side of history + that we cache renames for (MERGE_SIDE1 as far as this document is + concerned; see the assumptions section). Two interesting sub-notes + about these counts: + + * If we need to perform rename-detection again on the given side (e.g. + some paths are relevant for rename detection that weren't before), + then we clear dir_rename_counts and recompute it, making use of + cached_pairs. The reason it is important to do this is optimizations + around RELEVANT_LOCATION exist to prevent us from computing + unnecessary renames for directory rename detection and from computing + dir_rename_counts for irrelevant directories; but those same renames + or directories may become necessary for subsequent merges. The + easiest way to "fix up" dir_rename_counts in such cases is to just + recompute it. + + * If we prune rename/rename(1to1) entries from the cache, then we also + need to update dir_rename_counts to decrement the counts for the + involved directory and any relevant parent directories (to undo what + update_dir_rename_counts() in diffcore-rename.c incremented when the + rename was initially found). If we instead just disable the + remembering renames optimization when the exceedingly rare + rename/rename(1to1) cases occur, then dir_rename_counts will get + re-computed the next time rename detection occurs, as noted above. + + * the side with multiple commits to pick, is the side of history that we + do NOT cache renames for. Thus, there are no additional commits to + change the number of renames in a directory, except for those done by + directory rename detection (which always pad the majority). + + * the "renames" we cache are modified slightly by any directory rename, + as noted below. + +Now, with those notes out of the way, let's go through the four cases +in order: + +Case 1: MERGE_SIDE1 renames old dir, MERGE_SIDE2 adds new file to old dir + + This case looks like this: + + MERGE_BASE: E, Has olddir/ + MERGE_SIDE1: G, Renames olddir/ -> newdir/ + MERGE_SIDE2: A, Adds olddir/newfile + => creates A', With newdir/newfile + + MERGE_BASE: A, Has olddir/newfile + MERGE_SIDE1: A', Has newdir/newfile + MERGE_SIDE2: B, Modifies olddir/newfile + => expected B', with threeway-merged newdir/newfile from above + + In this case, with the optimization, note that after the first commit: + * MERGE_SIDE1 remembers olddir/ -> newdir/ + * MERGE_SIDE1 has cached olddir/newfile -> newdir/newfile + Given the cached rename noted above, the second merge can proceed as + expected without needing to perform rename detection from A -> A'. + +Case 2: MERGE_SIDE1 renames old dir, MERGE_SIDE2 renames file into old dir + + This case looks like this: + MERGE_BASE: E oldfile, olddir/ + MERGE_SIDE1: G oldfile, olddir/ -> newdir/ + MERGE_SIDE2: A oldfile -> olddir/newfile + => creates A', With newdir/newfile representing original oldfile + + MERGE_BASE: A olddir/newfile + MERGE_SIDE1: A' newdir/newfile + MERGE_SIDE2: B modify olddir/newfile + => expected B', with threeway-merged newdir/newfile from above + + In this case, with the optimization, note that after the first commit: + * MERGE_SIDE1 remembers olddir/ -> newdir/ + * MERGE_SIDE1 has cached olddir/newfile -> newdir/newfile + (NOT oldfile -> newdir/newfile; compare to case with + (p->status == 'R' && new_path) in possibly_cache_new_pair()) + + Given the cached rename noted above, the second merge can proceed as + expected without needing to perform rename detection from A -> A'. + +Case 3: MERGE_SIDE1 adds new file to old dir, MERGE_SIDE2 renames old dir + + This case looks like this: + + MERGE_BASE: E, Has olddir/ + MERGE_SIDE1: G, Adds olddir/newfile + MERGE_SIDE2: A, Renames olddir/ -> newdir/ + => creates A', With newdir/newfile + + MERGE_BASE: A, Has newdir/, but no notion of newdir/newfile + MERGE_SIDE1: A', Has newdir/newfile + MERGE_SIDE2: B, Has newdir/, but no notion of newdir/newfile + => expected B', with newdir/newfile from A' + + In this case, with the optimization, note that after the first commit there + were no renames on MERGE_SIDE1, and any renames on MERGE_SIDE2 are tossed. + But the second merge didn't need any renames so this is fine. + +Case 4: MERGE_SIDE1 renames file into old dir, MERGE_SIDE2 renames old dir + + This case looks like this: + + MERGE_BASE: E, Has olddir/ + MERGE_SIDE1: G, Renames oldfile -> olddir/newfile + MERGE_SIDE2: A, Renames olddir/ -> newdir/ + => creates A', With newdir/newfile representing original oldfile + + MERGE_BASE: A, Has oldfile + MERGE_SIDE1: A', Has newdir/newfile + MERGE_SIDE2: B, Modifies oldfile + => expected B', with threeway-merged newdir/newfile from above + + In this case, with the optimization, note that after the first commit: + * MERGE_SIDE1 remembers oldfile -> newdir/newfile + (NOT oldfile -> olddir/newfile; compare to case of second + block under p->status == 'R' in possibly_cache_new_pair()) + * MERGE_SIDE2 renames are tossed because only MERGE_SIDE1 is remembered + + Given the cached rename noted above, the second merge can proceed as + expected without needing to perform rename detection from A -> A'. + +Finally, I'll just note here that interactions with the +skip-irrelevant-renames optimization means we sometimes don't detect +renames for any files within a directory that was renamed, in which +case we will not have been able to detect any rename for the directory +itself. In such a case, we do not know whether the directory was +renamed; we want to be careful to avoid cacheing some kind of "this +directory was not renamed" statement. If we did, then a subsequent +commit being rebased could add a file to the old directory, and the +user would expect it to end up in the correct directory -- something +our erroneous "this directory was not renamed" cache would preclude. diff --git a/Documentation/technical/sparse-index.txt b/Documentation/technical/sparse-index.txt new file mode 100644 index 0000000000..3b24c1a219 --- /dev/null +++ b/Documentation/technical/sparse-index.txt @@ -0,0 +1,208 @@ +Git Sparse-Index Design Document +================================ + +The sparse-checkout feature allows users to focus a working directory on +a subset of the files at HEAD. The cone mode patterns, enabled by +`core.sparseCheckoutCone`, allow for very fast pattern matching to +discover which files at HEAD belong in the sparse-checkout cone. + +Three important scale dimensions for a Git working directory are: + +* `HEAD`: How many files are present at `HEAD`? + +* Populated: How many files are within the sparse-checkout cone. + +* Modified: How many files has the user modified in the working directory? + +We will use big-O notation -- O(X) -- to denote how expensive certain +operations are in terms of these dimensions. + +These dimensions are ordered by their magnitude: users (typically) modify +fewer files than are populated, and we can only populate files at `HEAD`. + +Problems occur if there is an extreme imbalance in these dimensions. For +example, if `HEAD` contains millions of paths but the populated set has +only tens of thousands, then commands like `git status` and `git add` can +be dominated by operations that require O(`HEAD`) operations instead of +O(Populated). Primarily, the cost is in parsing and rewriting the index, +which is filled primarily with files at `HEAD` that are marked with the +`SKIP_WORKTREE` bit. + +The sparse-index intends to take these commands that read and modify the +index from O(`HEAD`) to O(Populated). To do this, we need to modify the +index format in a significant way: add "sparse directory" entries. + +With cone mode patterns, it is possible to detect when an entire +directory will have its contents outside of the sparse-checkout definition. +Instead of listing all of the files it contains as individual entries, a +sparse-index contains an entry with the directory name, referencing the +object ID of the tree at `HEAD` and marked with the `SKIP_WORKTREE` bit. +If we need to discover the details for paths within that directory, we +can parse trees to find that list. + +At time of writing, sparse-directory entries violate expectations about the +index format and its in-memory data structure. There are many consumers in +the codebase that expect to iterate through all of the index entries and +see only files. In fact, these loops expect to see a reference to every +staged file. One way to handle this is to parse trees to replace a +sparse-directory entry with all of the files within that tree as the index +is loaded. However, parsing trees is slower than parsing the index format, +so that is a slower operation than if we left the index alone. The plan is +to make all of these integrations "sparse aware" so this expansion through +tree parsing is unnecessary and they use fewer resources than when using a +full index. + +The implementation plan below follows four phases to slowly integrate with +the sparse-index. The intention is to incrementally update Git commands to +interact safely with the sparse-index without significant slowdowns. This +may not always be possible, but the hope is that the primary commands that +users need in their daily work are dramatically improved. + +Phase I: Format and initial speedups +------------------------------------ + +During this phase, Git learns to enable the sparse-index and safely parse +one. Protections are put in place so that every consumer of the in-memory +data structure can operate with its current assumption of every file at +`HEAD`. + +At first, every index parse will call a helper method, +`ensure_full_index()`, which scans the index for sparse-directory entries +(pointing to trees) and replaces them with the full list of paths (with +blob contents) by parsing tree objects. This will be slower in all cases. +The only noticeable change in behavior will be that the serialized index +file contains sparse-directory entries. + +To start, we use a new required index extension, `sdir`, to allow +inserting sparse-directory entries into indexes with file format +versions 2, 3, and 4. This prevents Git versions that do not understand +the sparse-index from operating on one, while allowing tools that do not +understand the sparse-index to operate on repositories as long as they do +not interact with the index. A new format, index v5, will be introduced +that includes sparse-directory entries by default. It might also +introduce other features that have been considered for improving the +index, as well. + +Next, consumers of the index will be guarded against operating on a +sparse-index by inserting calls to `ensure_full_index()` or +`expand_index_to_path()`. If a specific path is requested, then those will +be protected from within the `index_file_exists()` and `index_name_pos()` +API calls: they will call `ensure_full_index()` if necessary. The +intention here is to preserve existing behavior when interacting with a +sparse-checkout. We don't want a change to happen by accident, without +tests. Many of these locations may not need any change before removing the +guards, but we should not do so without tests to ensure the expected +behavior happens. + +It may be desirable to _change_ the behavior of some commands in the +presence of a sparse index or more generally in any sparse-checkout +scenario. In such cases, these should be carefully communicated and +tested. No such behavior changes are intended during this phase. + +During a scan of the codebase, not every iteration of the cache entries +needs an `ensure_full_index()` check. The basic reasons include: + +1. The loop is scanning for entries with non-zero stage. These entries + are not collapsed into a sparse-directory entry. + +2. The loop is scanning for submodules. These entries are not collapsed + into a sparse-directory entry. + +3. The loop is part of the index API, especially around reading or + writing the format. + +4. The loop is checking for correct order of cache entries and that is + correct if and only if the sparse-directory entries are in the correct + location. + +5. The loop ignores entries with the `SKIP_WORKTREE` bit set, or is + otherwise already aware of sparse directory entries. + +6. The sparse-index is disabled at this point when using the split-index + feature, so no effort is made to protect the split-index API. + +Even after inserting these guards, we will keep expanding sparse-indexes +for most Git commands using the `command_requires_full_index` repository +setting. This setting will be on by default and disabled one builtin at a +time until we have sufficient confidence that all of the index operations +are properly guarded. + +To complete this phase, the commands `git status` and `git add` will be +integrated with the sparse-index so that they operate with O(Populated) +performance. They will be carefully tested for operations within and +outside the sparse-checkout definition. + +Phase II: Careful integrations +------------------------------ + +This phase focuses on ensuring that all index extensions and APIs work +well with a sparse-index. This requires significant increases to our test +coverage, especially for operations that interact with the working +directory outside of the sparse-checkout definition. Some of these +behaviors may not be the desirable ones, such as some tests already +marked for failure in `t1092-sparse-checkout-compatibility.sh`. + +The index extensions that may require special integrations are: + +* FS Monitor +* Untracked cache + +While integrating with these features, we should look for patterns that +might lead to better APIs for interacting with the index. Coalescing +common usage patterns into an API call can reduce the number of places +where sparse-directories need to be handled carefully. + +Phase III: Important command speedups +------------------------------------- + +At this point, the patterns for testing and implementing sparse-directory +logic should be relatively stable. This phase focuses on updating some of +the most common builtins that use the index to operate as O(Populated). +Here is a potential list of commands that could be valuable to integrate +at this point: + +* `git commit` +* `git checkout` +* `git merge` +* `git rebase` + +Hopefully, commands such as `git merge` and `git rebase` can benefit +instead from merge algorithms that do not use the index as a data +structure, such as the merge-ORT strategy. As these topics mature, we +may enable the ORT strategy by default for repositories using the +sparse-index feature. + +Along with `git status` and `git add`, these commands cover the majority +of users' interactions with the working directory. In addition, we can +integrate with these commands: + +* `git grep` +* `git rm` + +These have been proposed as some whose behavior could change when in a +repo with a sparse-checkout definition. It would be good to include this +behavior automatically when using a sparse-index. Some clarity is needed +to make the behavior switch clear to the user. + +This phase is the first where parallel work might be possible without too +much conflicts between topics. + +Phase IV: The long tail +----------------------- + +This last phase is less a "phase" and more "the new normal" after all of +the previous work. + +To start, the `command_requires_full_index` option could be removed in +favor of expanding only when hitting an API guard. + +There are many Git commands that could use special attention to operate as +O(Populated), while some might be so rare that it is acceptable to leave +them with additional overhead when a sparse-index is present. + +Here are some commands that might be useful to update: + +* `git sparse-checkout set` +* `git am` +* `git clean` +* `git stash` diff --git a/Documentation/user-manual.txt b/Documentation/user-manual.txt index f9e54b8674..865074bed4 100644 --- a/Documentation/user-manual.txt +++ b/Documentation/user-manual.txt @@ -2792,7 +2792,7 @@ A fast-forward looks something like this: In some cases it is possible that the new head will *not* actually be a descendant of the old head. For example, the developer may have -realized she made a serious mistake, and decided to backtrack, +realized a serious mistake was made and decided to backtrack, resulting in a situation like: ................................................ @@ -3190,7 +3190,7 @@ that *updated* thing--the old state that you added originally ends up not being pointed to by any commit or tree, so it's now a dangling blob object. -Similarly, when the "recursive" merge strategy runs, and finds that +Similarly, when the "ort" merge strategy runs, and finds that there are criss-cross merges and thus more than one merge base (which is fairly unusual, but it does happen), it will generate one temporary midway tree (or possibly even more, if you had lots of criss-crossing |