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2017-02-15Merge branch 'rs/swap'Libravatar Junio C Hamano1-8/+4
Code clean-up. * rs/swap: graph: use SWAP macro diff: use SWAP macro use SWAP macro apply: use SWAP macro add SWAP macro
2017-02-10Merge branch 'jk/log-graph-name-only'Libravatar Junio C Hamano1-0/+1
"git log --graph" did not work well with "--name-only", even though other forms of "diff" output were handled correctly. * jk/log-graph-name-only: diff: print line prefix for --name-only output
2017-02-08diff: print line prefix for --name-only outputLibravatar Jeff King1-0/+1
If you run "git log --graph --name-only", the pathnames are not indented to go along with their matching commits (unlike all of the other diff formats). We need to output the line prefix for each item before writing it. The tests cover both --name-status and --name-only. The former actually gets this right already, because it builds on the --raw format functions. It's only --name-only which uses its own code (and this fix mirrors the code in diff_flush_raw()). Note that the tests don't follow our usual style of setting up the "expect" output inside the test block. This matches the surrounding style, but more importantly it is easier to read: we don't have to worry about embedded single-quotes, and the leading indentation is more obvious. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-30use oid_to_hex_r() for converting struct object_id hashes to hex stringsLibravatar René Scharfe1-1/+1
Patch generated by Coccinelle and contrib/coccinelle/object_id.cocci. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-30diff: use SWAP macroLibravatar René Scharfe1-3/+1
Use the macro SWAP to exchange the value of pairs of variables instead of swapping them manually with the help of a temporary variable. The resulting code is shorter and easier to read. The two cases were not transformed by the semantic patch swap.cocci because it's extra careful and handles only cases where the types of all variables are the same -- and here we swap two ints and use an unsigned temporary variable for that. Nevertheless the conversion is safe, as the value range is preserved with and without the patch. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-30use SWAP macroLibravatar René Scharfe1-5/+3
Apply the semantic patch swap.cocci to convert hand-rolled swaps to use the macro SWAP. The resulting code is shorter and easier to read, the object code is effectively unchanged. The patch for object.c had to be hand-edited in order to preserve the comment before the change; Coccinelle tried to eat it for some reason. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-12diff: add interhunk context config optionLibravatar Vegard Nossum1-0/+8
The --inter-hunk-context= option was added in commit 6d0e674a5754 ("diff: add option to show context between close hunks"). This patch allows configuring a default for this option. Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-10Merge branch 'jc/retire-compaction-heuristics'Libravatar Junio C Hamano1-20/+3
"git diff" and its family had two experimental heuristics to shift the contents of a hunk to make the patch easier to read. One of them turns out to be better than the other, so leave only the "--indent-heuristic" option and remove the other one. * jc/retire-compaction-heuristics: diff: retire "compaction" heuristics
2016-12-23diff: retire "compaction" heuristicsLibravatar Junio C Hamano1-20/+3
When a patch inserts a block of lines, whose last lines are the same as the existing lines that appear before the inserted block, "git diff" can choose any place between these existing lines as the boundary between the pre-context and the added lines (adjusting the end of the inserted block as appropriate) to come up with variants of the same patch, and some variants are easier to read than others. We have been trying to improve the choice of this boundary, and Git 2.11 shipped with an experimental "compaction-heuristic". Since then another attempt to improve the logic further resulted in a new "indent-heuristic" logic. It is agreed that the latter gives better result overall, and the former outlived its usefulness. Retire "compaction", and keep "indent" as an experimental feature. The latter hopefully will be turned on by default in a future release, but that should be done as a separate step. Suggested-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-12-08diff: handle --no-abbrev in no-index caseLibravatar Jack Bates1-1/+5
There are two different places where the --no-abbrev option is parsed, and two different places where SHA-1s are abbreviated. We normally parse --no-abbrev with setup_revisions(), but in the no-index case, "git diff" calls diff_opt_parse() directly, and diff_opt_parse() didn't handle --no-abbrev until now. (It did handle --abbrev, however.) We normally abbreviate SHA-1s with find_unique_abbrev(), but commit 4f03666 ("diff: handle sha1 abbreviations outside of repository, 2016-10-20) recently introduced a special case when you run "git diff" outside of a repository. setup_revisions() does also call diff_opt_parse(), but not for --abbrev or --no-abbrev, which it handles itself. setup_revisions() sets rev_info->abbrev, and later copies that to diff_options->abbrev. It handles --no-abbrev by setting abbrev to zero. (This change doesn't touch that.) Setting abbrev to zero was broken in the outside-of-a-repository special case, which until now resulted in a truly zero-length SHA-1, rather than taking zero to mean do not abbreviate. The only way to trigger this bug, however, was by running "git diff --raw" without either the --abbrev or --no-abbrev options, because 1) without --raw it doesn't respect abbrev (which is bizarre, but has been that way forever), 2) we silently clamp --abbrev=0 to MINIMUM_ABBREV, and 3) --no-abbrev wasn't handled until now. The outside-of-a-repository case is one of three no-index cases. The other two are when one of the files you're comparing is outside of the repository you're in, and the --no-index option. Signed-off-by: Jack Bates <jack@nottheoilrig.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-11-17Merge branch 'tk/diffcore-delta-remove-unused'Libravatar Junio C Hamano1-1/+1
Code cleanup. * tk/diffcore-delta-remove-unused: diffcore-delta: remove unused parameter to diffcore_count_changes()
2016-11-14diffcore-delta: remove unused parameter to diffcore_count_changes()Libravatar Tobias Klauser1-1/+1
The delta_limit parameter to diffcore_count_changes() has been unused since commit ba23bbc8e ("diffcore-delta: make change counter to byte oriented again.", 2006-03-04). Remove the parameter and adjust all callers. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-27Merge branch 'nd/ita-empty-commit'Libravatar Junio C Hamano1-0/+4
When new paths were added by "git add -N" to the index, it was enough to circumvent the check by "git commit" to refrain from making an empty commit without "--allow-empty". The same logic prevented "git status" to show such a path as "new file" in the "Changes not staged for commit" section. * nd/ita-empty-commit: commit: don't be fooled by ita entries when creating initial commit commit: fix empty commit creation when there's no changes but ita entries diff: add --ita-[in]visible-in-index diff-lib: allow ita entries treated as "not yet exist in index"
2016-10-27Merge branch 'jk/no-looking-at-dotgit-outside-repo'Libravatar Junio C Hamano1-16/+29
Update "git diff --no-index" codepath not to try to peek into .git/ directory that happens to be under the current directory, when we know we are operating outside any repository. * jk/no-looking-at-dotgit-outside-repo: diff: handle sha1 abbreviations outside of repository diff_aligned_abbrev: use "struct oid" diff_unique_abbrev: rename to diff_aligned_abbrev find_unique_abbrev: use 4-buffer ring test-*-cache-tree: setup git dir read info/{attributes,exclude} only when in repository
2016-10-27Merge branch 'lt/abbrev-auto'Libravatar Junio C Hamano1-1/+1
Allow the default abbreviation length, which has historically been 7, to scale as the repository grows. The logic suggests to use 12 hexdigits for the Linux kernel, and 9 to 10 for Git itself. * lt/abbrev-auto: abbrev: auto size the default abbreviation abbrev: prepare for new world order abbrev: add FALLBACK_DEFAULT_ABBREV to prepare for auto sizing
2016-10-26diff: handle sha1 abbreviations outside of repositoryLibravatar Jeff King1-4/+17
When generating diffs outside a repository (e.g., with "diff --no-index"), we may write abbreviated sha1s as part of "--raw" output or the "index" lines of "--patch" output. Since we have no object database, we never find any collisions, and these sha1s get whatever static abbreviation length is configured (typically 7). However, we do blindly look in ".git/objects" to see if any objects exist, even though we know we are not in a repository. This is usually harmless because such a directory is unlikely to exist, but could be wrong in rare circumstances. Let's instead notice when we are not in a repository and behave as if the object database is empty (i.e., just use the default abbrev length). It would perhaps make sense to be conservative and show full sha1s in that case, but showing the default abbreviation is what we've always done (and is certainly less ugly). Note that this does mean that: cd /not/a/repo GIT_OBJECT_DIRECTORY=/some/real/objdir git diff --no-index ... used to look for collisions in /some/real/objdir but now does not. This could be considered either a bugfix (we do not look at objects if we have no repository) or a regression, but it seems unlikely that anybody would care much either way. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-26diff_aligned_abbrev: use "struct oid"Libravatar Jeff King1-9/+11
Since we're modifying this function anyway, it's a good time to update it to the more modern "struct oid". We can also drop some of the magic numbers in favor of GIT_SHA1_HEXSZ, along with some descriptive comments. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-26diff_unique_abbrev: rename to diff_aligned_abbrevLibravatar Jeff King1-7/+3
The word "align" describes how the function actually differs from find_unique_abbrev, and will make it less confusing when we add more diff-specific abbrevation functions that do not do this alignment. Since this is a globally available function, let's also move its descriptive comment to the header file, where we typically document function interfaces. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-26Merge branch 'va/i18n'Libravatar Junio C Hamano1-7/+7
More i18n. * va/i18n: i18n: diff: mark warnings for translation i18n: credential-cache--daemon: mark advice for translation i18n: convert mark error messages for translation i18n: apply: mark error message for translation i18n: apply: mark error messages for translation i18n: apply: mark info messages for translation i18n: apply: mark plural string for translation
2016-10-26Merge branch 'jc/ws-error-highlight'Libravatar Junio C Hamano1-34/+55
"git diff/log --ws-error-highlight=<kind>" lacked the corresponding configuration variable to set it by default. * jc/ws-error-highlight: diff: introduce diff.wsErrorHighlight option diff.c: move ws-error-highlight parsing helpers up diff.c: refactor parse_ws_error_highlight() t4015: split out the "setup" part of ws-error-highlight test
2016-10-26Merge branch 'jc/diff-unique-abbrev-comments'Libravatar Junio C Hamano1-1/+22
A bit more comments in a tricky code. * jc/diff-unique-abbrev-comments: diff_unique_abbrev(): document its assumption and limitation
2016-10-24diff: add --ita-[in]visible-in-indexLibravatar Nguyễn Thái Ngọc Duy1-0/+4
The option --ita-invisible-in-index exposes the "ita_invisible_in_index" diff flag to outside to allow easier experimentation with this new mode. The "plan" is to make --ita-invisible-in-index default to keep consistent behavior with 'status' and 'commit', but a bunch other commands like 'apply', 'merge', 'reset'.... need to be taken into consideration as well. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-17i18n: diff: mark warnings for translationLibravatar Vasco Almeida1-7/+7
Mark rename_limit_warning and degrade_cc_to_c_warning and rename_limit_warning for translation. Signed-off-by: Vasco Almeida <vascomalmeida@sapo.pt> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-10Merge branch 'rs/qsort'Libravatar Junio C Hamano1-3/+3
We call "qsort(array, nelem, sizeof(array[0]), fn)", and most of the time third parameter is redundant. A new QSORT() macro lets us omit it. * rs/qsort: show-branch: use QSORT use QSORT, part 2 coccicheck: use --all-includes by default remove unnecessary check before QSORT use QSORT add QSORT
2016-10-06Merge branch 'rs/cocci'Libravatar Junio C Hamano1-1/+1
Code clean-up with help from coccinelle tool continues. * rs/cocci: coccicheck: make transformation for strbuf_addf(sb, "...") more precise use strbuf_add_unique_abbrev() for adding short hashes, part 2 use strbuf_addstr() instead of strbuf_addf() with "%s", part 2 gitignore: ignore output files of coccicheck make target
2016-10-04diff: introduce diff.wsErrorHighlight optionLibravatar Junio C Hamano1-1/+10
With the preparatory steps, it has become trivial to teach the system a new diff.wsErrorHighlight configuration that gives the default value for --ws-error-highlight command line option. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-04diff.c: move ws-error-highlight parsing helpers upLibravatar Junio C Hamano1-37/+37
These need to be usable from git_diff_ui_config() code to help parsing a configuration variable, so move them up. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-04diff.c: refactor parse_ws_error_highlight()Libravatar Junio C Hamano1-5/+16
Rename the function to parse_ws_error_highlight_opt(), because it is meant to parse a command line option, and then refactor the meat of the function into a helper function that reports the parsed result which is typically a small unsigned int (these are OR'ed bitmask after all), or a negative offset that indicates where in the input string a parse error happened. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-03abbrev: prepare for new world orderLibravatar Junio C Hamano1-1/+1
The code that sets custom abbreviation length, in response to command line argument, often does something like this: if (skip_prefix(arg, "--abbrev=", &arg)) abbrev = atoi(arg); else if (!strcmp("--abbrev", &arg)) abbrev = DEFAULT_ABBREV; /* make the value sane */ if (abbrev < 0 || 40 < abbrev) abbrev = ... some sane value ... However, it is pointless to sanity-check and tweak the value obtained from DEFAULT_ABBREV. We are going to allow it to be initially set to -1 to signal that the default abbreviation length must be auto sized upon the first request to abbreviate, based on the number of objects in the repository, and when that happens, rejecting or tweaking a negative value to a "saner" one will negatively interfere with the auto sizing. The codepaths for git rev-parse --short <object> git diff --raw --abbrev do exactly that; allow them to pass possibly negative abbrevs intact, that will come from DEFAULT_ABBREV in the future. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-30diff_unique_abbrev(): document its assumption and limitationLibravatar Junio C Hamano1-1/+22
This function is used to add "..." to displayed object names in "diff --raw --abbrev[=<n>]" output. It bases its behaviour on an untold assumption that the abbreviation length requested by the caller is "reasonble", i.e. most of the objects will abbreviate within the requested length and the resulting length would never exceed it by more than a few hexdigits (otherwise the resulting columns would not align). Explain that in a comment. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-29Merge branch 'js/regexec-buf' into maintLibravatar Junio C Hamano1-1/+2
Some codepaths in "git diff" used regexec(3) on a buffer that was mmap(2)ed, which may not have a terminating NUL, leading to a read beyond the end of the mapped region. This was fixed by introducing a regexec_buf() helper that takes a <ptr,len> pair with REG_STARTEND extension. * js/regexec-buf: regex: use regexec_buf() regex: add regexec_buf() that can work on a non NUL-terminated string regex: -G<pattern> feeds a non NUL-terminated string to regexec() and fails
2016-09-29use QSORTLibravatar René Scharfe1-3/+3
Apply the semantic patch contrib/coccinelle/qsort.cocci to the code base, replacing calls of qsort(3) with QSORT. The resulting code is shorter and supports empty arrays with NULL pointers. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-27use strbuf_add_unique_abbrev() for adding short hashes, part 2Libravatar René Scharfe1-1/+1
Call strbuf_add_unique_abbrev() to add abbreviated hashes to strbufs instead of taking detours through find_unique_abbrev() and its static buffer. This is shorter and a bit more efficient. 1eb47f167d65d1d305b9c196a1bb40eb96117cb1 already converted six cases, this patch covers three more. A semantic patch for Coccinelle is included for easier checking for new cases that might be introduced in the future. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-26Merge branch 'js/regexec-buf'Libravatar Junio C Hamano1-1/+2
Some codepaths in "git diff" used regexec(3) on a buffer that was mmap(2)ed, which may not have a terminating NUL, leading to a read beyond the end of the mapped region. This was fixed by introducing a regexec_buf() helper that takes a <ptr,len> pair with REG_STARTEND extension. * js/regexec-buf: regex: use regexec_buf() regex: add regexec_buf() that can work on a non NUL-terminated string regex: -G<pattern> feeds a non NUL-terminated string to regexec() and fails
2016-09-26Merge branch 'va/i18n-more'Libravatar Junio C Hamano1-5/+10
Even more i18n. * va/i18n-more: i18n: stash: mark messages for translation i18n: notes-merge: mark die messages for translation i18n: ident: mark hint for translation i18n: i18n: diff: mark die messages for translation i18n: connect: mark die messages for translation i18n: commit: mark message for translation
2016-09-26Merge branch 'mh/diff-indent-heuristic'Libravatar Junio C Hamano1-7/+29
Output from "git diff" can be made easier to read by selecting which lines are common and which lines are added/deleted intelligently when the lines before and after the changed section are the same. A command line option is added to help with the experiment to find a good heuristics. * mh/diff-indent-heuristic: blame: honor the diff heuristic options and config parse-options: add parse_opt_unknown_cb() diff: improve positioning of add/delete blocks in diffs xdl_change_compact(): introduce the concept of a change group recs_match(): take two xrecord_t pointers as arguments is_blank_line(): take a single xrecord_t as argument xdl_change_compact(): only use heuristic if group can't be matched xdl_change_compact(): fix compaction heuristic to adjust ixo
2016-09-21regex: use regexec_buf()Libravatar Johannes Schindelin1-1/+2
The new regexec_buf() function operates on buffers with an explicitly specified length, rather than NUL-terminated strings. We need to use this function whenever the buffer we want to pass to regexec(3) may have been mmap(2)ed (and is hence not NUL-terminated). Note: the original motivation for this patch was to fix a bug where `git diff -G <regex>` would crash. This patch converts more callers, though, some of which allocated to construct NUL-terminated strings, or worse, modified buffers to temporarily insert NULs while calling regexec(3). By converting them to use regexec_buf(), the code has become much cleaner. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-21i18n: i18n: diff: mark die messages for translationLibravatar Jean-Noël AVILA1-5/+10
While marking individual messages for translation, consolidate some messages "option 'foo' requires a value" that is used for many options into one by introducing a helper function to die with the message with the option name embedded in it, and ask the translators to localize that single message instead. Signed-off-by: Vasco Almeida <vascomalmeida@sapo.pt> Signed-off-by: Jean-Noel Avila <jn.avila@free.fr> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-19Merge branch 'bc/object-id'Libravatar Junio C Hamano1-1/+1
The "unsigned char sha1[20]" to "struct object_id" conversion continues. Notable changes in this round includes that ce->sha1, i.e. the object name recorded in the cache_entry, turns into an object_id. It had merge conflicts with a few topics in flight (Christian's "apply.c split", Dscho's "cat-file --filters" and Jeff Hostetler's "status --porcelain-v2"). Extra sets of eyes double-checking for mismerges are highly appreciated. * bc/object-id: builtin/reset: convert to use struct object_id builtin/commit-tree: convert to struct object_id builtin/am: convert to struct object_id refs: add an update_ref_oid function. sha1_name: convert get_sha1_mb to struct object_id builtin/update-index: convert file to struct object_id notes: convert init_notes to use struct object_id builtin/rm: convert to use struct object_id builtin/blame: convert file to use struct object_id Convert read_mmblob to take struct object_id. notes-merge: convert struct notes_merge_pair to struct object_id builtin/checkout: convert some static functions to struct object_id streaming: make stream_blob_to_fd take struct object_id builtin: convert textconv_object to use struct object_id builtin/cat-file: convert some static functions to struct object_id builtin/cat-file: convert struct expand_data to use struct object_id builtin/log: convert some static functions to use struct object_id builtin/blame: convert struct origin to use struct object_id builtin/apply: convert static functions to struct object_id cache: convert struct cache_entry to use struct object_id
2016-09-19blame: honor the diff heuristic options and configLibravatar Michael Haggerty1-12/+17
Teach "git blame" and "git annotate" the --compaction-heuristic and --indent-heuristic options that are now supported by "git diff". Also teach them to honor the `diff.compactionHeuristic` and `diff.indentHeuristic` configuration options. It would be conceivable to introduce separate configuration options for "blame" and "annotate"; for example `blame.compactionHeuristic` and `blame.indentHeuristic`. But it would be confusing to users if blame output is inconsistent with diff output, so it makes more sense for them to respect the same configuration. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-19diff: improve positioning of add/delete blocks in diffsLibravatar Michael Haggerty1-3/+20
Some groups of added/deleted lines in diffs can be slid up or down, because lines at the edges of the group are not unique. Picking good shifts for such groups is not a matter of correctness but definitely has a big effect on aesthetics. For example, consider the following two diffs. The first is what standard Git emits: --- a/9c572b21dd090a1e5c5bb397053bf8043ffe7fb4:git-send-email.perl +++ b/6dcfa306f2b67b733a7eb2d7ded1bc9987809edb:git-send-email.perl @@ -231,6 +231,9 @@ if (!defined $initial_reply_to && $prompting) { } if (!$smtp_server) { + $smtp_server = $repo->config('sendemail.smtpserver'); +} +if (!$smtp_server) { foreach (qw( /usr/sbin/sendmail /usr/lib/sendmail )) { if (-x $_) { $smtp_server = $_; The following diff is equivalent, but is obviously preferable from an aesthetic point of view: --- a/9c572b21dd090a1e5c5bb397053bf8043ffe7fb4:git-send-email.perl +++ b/6dcfa306f2b67b733a7eb2d7ded1bc9987809edb:git-send-email.perl @@ -230,6 +230,9 @@ if (!defined $initial_reply_to && $prompting) { $initial_reply_to =~ s/(^\s+|\s+$)//g; } +if (!$smtp_server) { + $smtp_server = $repo->config('sendemail.smtpserver'); +} if (!$smtp_server) { foreach (qw( /usr/sbin/sendmail /usr/lib/sendmail )) { if (-x $_) { This patch teaches Git to pick better positions for such "diff sliders" using heuristics that take the positions of nearby blank lines and the indentation of nearby lines into account. The existing Git code basically always shifts such "sliders" as far down in the file as possible. The only exception is when the slider can be aligned with a group of changed lines in the other file, in which case Git favors depicting the change as one add+delete block rather than one add and a slightly offset delete block. This naive algorithm often yields ugly diffs. Commit d634d61ed6 improved the situation somewhat by preferring to position add/delete groups to make their last line a blank line, when that is possible. This heuristic does more good than harm, but (1) it can only help if there are blank lines in the right places, and (2) always picks the last blank line, even if there are others that might be better. The end result is that it makes perhaps 1/3 as many errors as the default Git algorithm, but that still leaves a lot of ugly diffs. This commit implements a new and much better heuristic for picking optimal "slider" positions using the following approach: First observe that each hypothetical positioning of a diff slider introduces two splits: one between the context lines preceding the group and the first added/deleted line, and the other between the last added/deleted line and the first line of context following it. It tries to find the positioning that creates the least bad splits. Splits are evaluated based only on the presence and locations of nearby blank lines, and the indentation of lines near the split. Basically, it prefers to introduce splits adjacent to blank lines, between lines that are indented less, and between lines with the same level of indentation. In more detail: 1. It measures the following characteristics of a proposed splitting position in a `struct split_measurement`: * the number of blank lines above the proposed split * whether the line directly after the split is blank * the number of blank lines following that line * the indentation of the nearest non-blank line above the split * the indentation of the line directly below the split * the indentation of the nearest non-blank line after that line 2. It combines the measured attributes using a bunch of empirically-optimized weighting factors to derive a `struct split_score` that measures the "badness" of splitting the text at that position. 3. It combines the `split_score` for the top and the bottom of the slider at each of its possible positions, and selects the position that has the best `split_score`. I determined the initial set of weighting factors by collecting a corpus of Git histories from 29 open-source software projects in various programming languages. I generated many diffs from this corpus, and determined the best positioning "by eye" for about 6600 diff sliders. I used about half of the repositories in the corpus (corresponding to about 2/3 of the sliders) as a training set, and optimized the weights against this corpus using a crude automated search of the parameter space to get the best agreement with the manually-determined values. Then I tested the resulting heuristic against the full corpus. The results are summarized in the following table, in column `indent-1`: | repository | count | Git 2.9.0 | compaction | compaction-fixed | indent-1 | indent-2 | | --------------------- | ----- | -------------- | -------------- | ---------------- | -------------- | -------------- | | afnetworking | 109 | 89 (81.7%) | 37 (33.9%) | 37 (33.9%) | 2 (1.8%) | 2 (1.8%) | | alamofire | 30 | 18 (60.0%) | 14 (46.7%) | 15 (50.0%) | 0 (0.0%) | 0 (0.0%) | | angular | 184 | 127 (69.0%) | 39 (21.2%) | 23 (12.5%) | 5 (2.7%) | 5 (2.7%) | | animate | 313 | 2 (0.6%) | 2 (0.6%) | 2 (0.6%) | 2 (0.6%) | 2 (0.6%) | | ant | 380 | 356 (93.7%) | 152 (40.0%) | 148 (38.9%) | 15 (3.9%) | 15 (3.9%) | * | bugzilla | 306 | 263 (85.9%) | 109 (35.6%) | 99 (32.4%) | 14 (4.6%) | 15 (4.9%) | * | corefx | 126 | 91 (72.2%) | 22 (17.5%) | 21 (16.7%) | 6 (4.8%) | 6 (4.8%) | | couchdb | 78 | 44 (56.4%) | 26 (33.3%) | 28 (35.9%) | 6 (7.7%) | 6 (7.7%) | * | cpython | 937 | 158 (16.9%) | 50 (5.3%) | 49 (5.2%) | 5 (0.5%) | 5 (0.5%) | * | discourse | 160 | 95 (59.4%) | 42 (26.2%) | 36 (22.5%) | 18 (11.2%) | 13 (8.1%) | | docker | 307 | 194 (63.2%) | 198 (64.5%) | 253 (82.4%) | 8 (2.6%) | 8 (2.6%) | * | electron | 163 | 132 (81.0%) | 38 (23.3%) | 39 (23.9%) | 6 (3.7%) | 6 (3.7%) | | git | 536 | 470 (87.7%) | 73 (13.6%) | 78 (14.6%) | 16 (3.0%) | 16 (3.0%) | * | gitflow | 127 | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | | ionic | 133 | 89 (66.9%) | 29 (21.8%) | 38 (28.6%) | 1 (0.8%) | 1 (0.8%) | | ipython | 482 | 362 (75.1%) | 167 (34.6%) | 169 (35.1%) | 11 (2.3%) | 11 (2.3%) | * | junit | 161 | 147 (91.3%) | 67 (41.6%) | 66 (41.0%) | 1 (0.6%) | 1 (0.6%) | * | lighttable | 15 | 5 (33.3%) | 0 (0.0%) | 2 (13.3%) | 0 (0.0%) | 0 (0.0%) | | magit | 88 | 75 (85.2%) | 11 (12.5%) | 9 (10.2%) | 1 (1.1%) | 0 (0.0%) | | neural-style | 28 | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | | nodejs | 781 | 649 (83.1%) | 118 (15.1%) | 111 (14.2%) | 4 (0.5%) | 5 (0.6%) | * | phpmyadmin | 491 | 481 (98.0%) | 75 (15.3%) | 48 (9.8%) | 2 (0.4%) | 2 (0.4%) | * | react-native | 168 | 130 (77.4%) | 79 (47.0%) | 81 (48.2%) | 0 (0.0%) | 0 (0.0%) | | rust | 171 | 128 (74.9%) | 30 (17.5%) | 27 (15.8%) | 16 (9.4%) | 14 (8.2%) | | spark | 186 | 149 (80.1%) | 52 (28.0%) | 52 (28.0%) | 2 (1.1%) | 2 (1.1%) | | tensorflow | 115 | 66 (57.4%) | 48 (41.7%) | 48 (41.7%) | 5 (4.3%) | 5 (4.3%) | | test-more | 19 | 15 (78.9%) | 2 (10.5%) | 2 (10.5%) | 1 (5.3%) | 1 (5.3%) | * | test-unit | 51 | 34 (66.7%) | 14 (27.5%) | 8 (15.7%) | 2 (3.9%) | 2 (3.9%) | * | xmonad | 23 | 22 (95.7%) | 2 (8.7%) | 2 (8.7%) | 1 (4.3%) | 1 (4.3%) | * | --------------------- | ----- | -------------- | -------------- | ---------------- | -------------- | -------------- | | totals | 6668 | 4391 (65.9%) | 1496 (22.4%) | 1491 (22.4%) | 150 (2.2%) | 144 (2.2%) | | totals (training set) | 4552 | 3195 (70.2%) | 1053 (23.1%) | 1061 (23.3%) | 86 (1.9%) | 88 (1.9%) | | totals (test set) | 2116 | 1196 (56.5%) | 443 (20.9%) | 430 (20.3%) | 64 (3.0%) | 56 (2.6%) | In this table, the numbers are the count and percentage of human-rated sliders that the corresponding algorithm got *wrong*. The columns are * "repository" - the name of the repository used. I used the diffs between successive non-merge commits on the HEAD branch of the corresponding repository. * "count" - the number of sliders that were human-rated. I chose most, but not all, sliders to rate from those among which the various algorithms gave different answers. * "Git 2.9.0" - the default algorithm used by `git diff` in Git 2.9.0. * "compaction" - the heuristic used by `git diff --compaction-heuristic` in Git 2.9.0. * "compaction-fixed" - the heuristic used by `git diff --compaction-heuristic` after the fixes from earlier in this patch series. Note that the results are not dramatically different than those for "compaction". Both produce non-ideal diffs only about 1/3 as often as the default `git diff`. * "indent-1" - the new `--indent-heuristic` algorithm, using the first set of weighting factors, determined as described above. * "indent-2" - the new `--indent-heuristic` algorithm, using the final set of weighting factors, determined as described below. * `*` - indicates that repo was part of training set used to determine the first set of weighting factors. The fact that the heuristic performed nearly as well on the test set as on the training set in column "indent-1" is a good indication that the heuristic was not over-trained. Given that fact, I ran a second round of optimization, using the entire corpus as the training set. The resulting set of weights gave the results in column "indent-2". These are the weights included in this patch. The final result gives consistently and significantly better results across the whole corpus than either `git diff` or `git diff --compaction-heuristic`. It makes only about 1/30 as many errors as the former and about 1/10 as many errors as the latter. (And a good fraction of the remaining errors are for diffs that involve weirdly-formatted code, sometimes apparently machine-generated.) The tools that were used to do this optimization and analysis, along with the human-generated data values, are recorded in a separate project [1]. This patch adds a new command-line option `--indent-heuristic`, and a new configuration setting `diff.indentHeuristic`, that activate this heuristic. This interface is only meant for testing purposes, and should be finalized before including this change in any release. [1] https://github.com/mhagger/diff-slider-tools Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-15Merge branch 'sb/diff-cleanup'Libravatar Junio C Hamano1-21/+10
Code cleanup. * sb/diff-cleanup: diff: remove dead code diff: omit found pointer from emit_callback diff.c: use diff_options directly
2016-09-12Merge branch 'jk/diff-submodule-diff-inline'Libravatar Junio C Hamano1-17/+37
The "git diff --submodule={short,log}" mechanism has been enhanced to allow "--submodule=diff" to show the patch between the submodule commits bound to the superproject. * jk/diff-submodule-diff-inline: diff: teach diff to display submodule difference with an inline diff submodule: refactor show_submodule_summary with helper function submodule: convert show_submodule_summary to use struct object_id * allow do_submodule_path to work even if submodule isn't checked out diff: prepare for additional submodule formats graph: add support for --line-prefix on all graph-aware output diff.c: remove output_prefix_length field cache: add empty_tree_oid object and helper function
2016-09-08diff: remove dead codeLibravatar Stefan Beller1-8/+0
When `len < 1`, len has to be 0 or negative, emit_line will then remove the first character and by then `len` would be negative. As this doesn't happen, it is safe to assume it is dead code. This continues to simplify the code, which was started in b8d9c1a66b (2009-09-03, diff.c: the builtin_diff() deals with only two-file comparison). Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-08diff: omit found pointer from emit_callbackLibravatar Stefan Beller1-4/+2
We keep the actual data in the diff options, which are just as accessible. Remove the pointer stored in struct emit_callback for readability. Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-08diff.c: use diff_options directlyLibravatar Stefan Beller1-11/+10
The value of `ecbdata->opt` is accessible via the short variable `o` already, so let's use that instead. Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-07cache: convert struct cache_entry to use struct object_idLibravatar brian m. carlson1-1/+1
Convert struct cache_entry to use struct object_id by applying the following semantic patch and the object_id transforms from contrib, plus the actual change to the struct: @@ struct cache_entry E1; @@ - E1.sha1 + E1.oid.hash @@ struct cache_entry *E1; @@ - E1->sha1 + E1->oid.hash Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-08-31diff: teach diff to display submodule difference with an inline diffLibravatar Jacob Keller1-9/+22
Teach git-diff and friends a new format for displaying the difference of a submodule. The new format is an inline diff of the contents of the submodule between the commit range of the update. This allows the user to see the actual code change caused by a submodule update. Add tests for the new format and option. Signed-off-by: Jacob Keller <jacob.keller@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-08-31submodule: convert show_submodule_summary to use struct object_id *Libravatar Jacob Keller1-1/+1
Since we're going to be changing this function in a future patch, lets go ahead and convert this to use object_id now. Signed-off-by: Jacob Keller <jacob.keller@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-08-31diff: prepare for additional submodule formatsLibravatar Jacob Keller1-6/+6
A future patch will add a new format for displaying the difference of a submodule. Make it easier by changing how we store the current selected format. Replace the DIFF_OPT flag with an enumeration, as each format will be mutually exclusive. Signed-off-by: Jacob Keller <jacob.keller@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>