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2018-08-15Merge branch 'es/diff-color-moved-fix'Libravatar Junio C Hamano1-1/+2
One of the "diff --color-moved" mode "dimmed_zebra" that was named in an unusual way has been deprecated and replaced by "dimmed-zebra". * es/diff-color-moved-fix: diff: --color-moved: rename "dimmed_zebra" to "dimmed-zebra"
2018-08-02Merge branch 'sb/diff-color-move-more'Libravatar Junio C Hamano1-2/+31
"git diff --color-moved" feature has further been tweaked. * sb/diff-color-move-more: diff.c: offer config option to control ws handling in move detection diff.c: add white space mode to move detection that allows indent changes diff.c: factor advance_or_nullify out of mark_color_as_moved diff.c: decouple white space treatment from move detection algorithm diff.c: add a blocks mode for moved code detection diff.c: adjust hash function signature to match hashmap expectation diff.c: do not pass diff options as keydata to hashmap t4015: avoid git as a pipe input xdiff/xdiffi.c: remove unneeded function declarations xdiff/xdiff.h: remove unused flags
2018-07-25diff: --color-moved: rename "dimmed_zebra" to "dimmed-zebra"Libravatar Eric Sunshine1-1/+2
The --color-moved "dimmed_zebra" mode (with an underscore) is an anachronism. Most options and modes are hyphenated. It is more difficult to type and somewhat more difficult to read than those which are hyphenated. Therefore, rename it to "dimmed-zebra", and nominally deprecate "dimmed_zebra". Signed-off-by: Eric Sunshine <sunshine@sunshineco.com> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-19diff.c: offer config option to control ws handling in move detectionLibravatar Stefan Beller1-2/+5
Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-19diff.c: add white space mode to move detection that allows indent changesLibravatar Stefan Beller1-0/+5
The option of --color-moved has proven to be useful as observed on the mailing list. However when refactoring sometimes the indentation changes, for example when partitioning a functions into smaller helper functions the code usually mostly moved around except for a decrease in indentation. To just review the moved code ignoring the change in indentation, a mode to ignore spaces in the move detection as implemented in a previous patch would be enough. However the whole move coloring as motivated in commit 2e2d5ac (diff.c: color moved lines differently, 2017-06-30), brought up the notion of the reviewer being able to trust the move of a "block". As there are languages such as python, which depend on proper relative indentation for the control flow of the program, ignoring any white space change in a block would not uphold the promises of 2e2d5ac that allows reviewers to pay less attention to the inside of a block, as inside the reviewer wants to assume the same program flow. This new mode of white space ignorance will take this into account and will only allow the same white space changes per line in each block. This patch even allows only for the same change at the beginning of the lines. As this is a white space mode, it is made exclusive to other white space modes in the move detection. This patch brings some challenges, related to the detection of blocks. We need a wide net to catch the possible moved lines, but then need to narrow down to check if the blocks are still intact. Consider this example (ignoring block sizes): - A - B - C + A + B + C At the beginning of a block when checking if there is a counterpart for A, we have to ignore all space changes. However at the following lines we have to check if the indent change stayed the same. Checking if the indentation change did stay the same, is done by computing the indentation change by the difference in line length, and then assume the change is only in the beginning of the longer line, the common tail is the same. That is why the test contains lines like: - <TAB> A ... + A <TAB> ... As the first line starting a block is caught using a compare function that ignores white spaces unlike the rest of the block, where the white space delta is taken into account for the comparison, we also have to think about the following situation: - A - B - A - B + A + B + A + B When checking if the first A (both in the + and - lines) is a start of a block, we have to check all 'A' and record all the white space deltas such that we can find the example above to be just one block that is indented. Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-17diff.c: decouple white space treatment from move detection algorithmLibravatar Stefan Beller1-0/+17
In the original implementation of the move detection logic the choice for ignoring white space changes is the same for the move detection as it is for the regular diff. Some cases came up where different treatment would have been nice. Allow the user to specify that white space should be ignored differently during detection of moved lines than during generation of added and removed lines. This is done by providing analogs to the --ignore-space-at-eol, -b, and -w options by introducing the option --color-moved-ws=<modes> with the modes named "ignore-space-at-eol", "ignore-space-change" and "ignore-all-space", which is used only during the move detection phase. As we change the default, we'll adjust the tests. For now we do not infer any options to treat white spaces in the move detection from the generic white space options given to diff. This can be tuned later to reasonable default. As we plan on adding more white space related options in a later patch, that interferes with the current white space options, use a flag field and clamp it down to XDF_WHITESPACE_FLAGS, as that (a) allows to easily check at parse time if we give invalid combinations and (b) can reuse parts of this patch. By having the white space treatment in its own option, we'll also make it easier for a later patch to have an config option for spaces in the move detection. Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-17diff.c: add a blocks mode for moved code detectionLibravatar Stefan Beller1-2/+6
The new "blocks" mode provides a middle ground between plain and zebra. It is as intuitive (few colors) as plain, but still has the requirement for a minimum of lines/characters to count a block as moved. Suggested-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> (https://public-inbox.org/git/87o9j0uljo.fsf@evledraar.gmail.com/) Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-19doc: fix typos in documentation and release notesLibravatar Karthikeyan Singaravelan1-1/+1
Signed-off-by: Karthikeyan Singaravelan <tir.karthi@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-06-18Merge branch 'rd/diff-options-typofix'Libravatar Junio C Hamano1-4/+4
Typofix. * rd/diff-options-typofix: diff-options.txt: fix minor typos, font inconsistencies, in docs
2018-06-11diff-options.txt: fix minor typos, font inconsistencies, in docsLibravatar Robert P. J. Day1-4/+4
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-04-25Merge branch 'en/doc-typoes'Libravatar Junio C Hamano1-2/+2
Docfix. * en/doc-typoes: Documentation: normalize spelling of 'normalised' Documentation: fix several one-character-off spelling errors
2018-04-09Documentation: fix several one-character-off spelling errorsLibravatar Elijah Newren1-2/+2
Signed-off-by: Elijah Newren <newren@gmail.com> Reviewed-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-03-14Merge branch 'nd/diff-stat-with-summary'Libravatar Junio C Hamano1-0/+8
"git diff" and friends learned "--compact-summary" that shows the information usually given with the "--summary" option on the same line as the diffstat output of the "--stat" option (which saves vertical space and keeps info on a single path at the same place). * nd/diff-stat-with-summary: diff: add --compact-summary diff.c: refactor pprint_rename() to use strbuf
2018-02-27diff: add --compact-summaryLibravatar Nguyễn Thái Ngọc Duy1-0/+8
Certain information is currently shown with --summary, but when used in combination with --stat it's a bit hard to read since info of the same file is in two places (--stat and --summary). On top of that, commits that add or remove files double the number of display lines, which could be a lot if you add or remove a lot of files. --compact-summary embeds most of --summary back in --stat in the little space between the file name part and the graph line, e.g. with commit 0433d533f1: Documentation/merge-config.txt | 4 + builtin/merge.c | 2 + ...-pull-verify-signatures.sh (new +x) | 81 ++++++++++++++ t/t7612-merge-verify-signatures.sh | 45 ++++++++ 4 files changed, 132 insertions(+) It helps both condensing information and saving some text space. What's new in diffstat is: - A new 0644 file is shown as (new) - A new 0755 file is shown as (new +x) - A new symlink is shown as (new +l) - A deleted file is shown as (gone) - A mode change adding executable bit is shown as (mode +x) - A mode change removing it is shown as (mode -x) Note that --compact-summary does not contain all the information --summary provides. Rewrite percentage is not shown but it could be added later, like R50% or C20%. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-01-23Merge branch 'sb/diff-blobfind-pickaxe'Libravatar Junio C Hamano1-0/+10
"diff" family of commands learned "--find-object=<object-id>" option to limit the findings to changes that involve the named object. * sb/diff-blobfind-pickaxe: diff: use HAS_MULTI_BITS instead of counting bits manually diff: properly error out when combining multiple pickaxe options diffcore: add a pickaxe option to find a specific blob diff: introduce DIFF_PICKAXE_KINDS_MASK diff: migrate diff_flags.pickaxe_ignore_case to a pickaxe_opts bit diff.h: make pickaxe_opts an unsigned bit field
2018-01-09Merge branch 'jk/doc-diff-options'Libravatar Junio C Hamano1-0/+6
Doc update. * jk/doc-diff-options: docs/diff-options: clarify scope of diff-filter types
2018-01-04diffcore: add a pickaxe option to find a specific blobLibravatar Stefan Beller1-0/+10
Sometimes users are given a hash of an object and they want to identify it further (ex.: Use verify-pack to find the largest blobs, but what are these? or [1]) One might be tempted to extend git-describe to also work with blobs, such that `git describe <blob-id>` gives a description as '<commit-ish>:<path>'. This was implemented at [2]; as seen by the sheer number of responses (>110), it turns out this is tricky to get right. The hard part to get right is picking the correct 'commit-ish' as that could be the commit that (re-)introduced the blob or the blob that removed the blob; the blob could exist in different branches. Junio hinted at a different approach of solving this problem, which this patch implements. Teach the diff machinery another flag for restricting the information to what is shown. For example: $ ./git log --oneline --find-object=v2.0.0:Makefile b2feb64309 Revert the whole "ask curl-config" topic for now 47fbfded53 i18n: only extract comments marked with "TRANSLATORS:" we observe that the Makefile as shipped with 2.0 was appeared in v1.9.2-471-g47fbfded53 and in v2.0.0-rc1-5-gb2feb6430b. The reason why these commits both occur prior to v2.0.0 are evil merges that are not found using this new mechanism. [1] https://stackoverflow.com/questions/223678/which-commit-has-this-blob [2] https://public-inbox.org/git/20171028004419.10139-1-sbeller@google.com/ Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-01-04docs/diff-options: clarify scope of diff-filter typesLibravatar Jeff King1-0/+6
The same document for "--diff-filter" is included by many programs in the diff family. Because it mentions all possible types (added, removed, etc), this may imply to the reader that all types can be generated by a particular command. But this isn't necessarily the case; "diff-files" cannot generally produce an "Added" entry, since the diff is limited to what is already in the index. Let's make it clear that the list here is the full one, and does not imply anything about what a particular invocation may produce. Note that conditionally including items (e.g., omitting "Added" in the git-diff-files manpage) isn't the right solution here for two reasons: - The problem isn't diff-files, but doing an index to working tree diff. "git diff" can do the same diff, but also has other modes where "Added" does show up. - The direction of the diff matters. Doing "diff-files -R" can get you Added entries (but not Deleted ones). So it's best just to explain that the set of available types depends on the specific diff invocation. Reported-by: John Cheng <johnlicheng@gmail.com> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-28diff: support anchoring line(s)Libravatar Jonathan Tan1-0/+10
Teach diff a new algorithm, one that attempts to prevent user-specified lines from appearing as a deletion or addition in the end result. The end user can use this by specifying "--anchored=<text>" one or more times when using Git commands like "diff" and "show". Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-27Merge branch 'jc/ignore-cr-at-eol'Libravatar Junio C Hamano1-0/+3
The "diff" family of commands learned to ignore differences in carriage return at the end of line. * jc/ignore-cr-at-eol: diff: --ignore-cr-at-eol xdiff: reassign xpparm_t.flags bits
2017-11-15Merge branch 'cn/diff-indent-no-longer-is-experimental' into maintLibravatar Junio C Hamano1-1/+6
Doc update. * cn/diff-indent-no-longer-is-experimental: diff: --indent-heuristic is no longer experimental
2017-11-08diff: --ignore-cr-at-eolLibravatar Junio C Hamano1-0/+3
A new option --ignore-cr-at-eol tells the diff machinery to treat a carriage-return at the end of a (complete) line as if it does not exist. Just like other "--ignore-*" options to ignore various kinds of whitespace differences, this will help reviewing the real changes you made without getting distracted by spurious CRLF<->LF conversion made by your editor program. Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de> [jch: squashed in command line completion by Dscho] Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-11-06Merge branch 'cn/diff-indent-no-longer-is-experimental'Libravatar Junio C Hamano1-1/+6
Doc update. * cn/diff-indent-no-longer-is-experimental: diff: --indent-heuristic is no longer experimental
2017-11-02diff: --indent-heuristic is no longer experimentalLibravatar Carlos Martín Nieto1-1/+6
This heuristic has been the default since 2.14 so we should not confuse our users by saying that it's experimental and off by default. Signed-off-by: Carlos Martín Nieto <cmn@dwim.me> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-26Merge branch 'jt/diff-color-move-fix'Libravatar Junio C Hamano1-5/+3
A handful of bugfixes and an improvement to "diff --color-moved". * jt/diff-color-move-fix: diff: define block by number of alphanumeric chars diff: respect MIN_BLOCK_LENGTH for last block diff: avoid redundantly clearing a flag
2017-08-26Merge branch 'sb/diff-color-move'Libravatar Junio C Hamano1-0/+36
"git diff" has been taught to optionally paint new lines that are the same as deleted lines elsewhere differently from genuinely new lines. * sb/diff-color-move: (25 commits) diff: document the new --color-moved setting diff.c: add dimming to moved line detection diff.c: color moved lines differently, plain mode diff.c: color moved lines differently diff.c: buffer all output if asked to diff.c: emit_diff_symbol learns about DIFF_SYMBOL_SUMMARY diff.c: emit_diff_symbol learns about DIFF_SYMBOL_STAT_SEP diff.c: convert word diffing to use emit_diff_symbol diff.c: convert show_stats to use emit_diff_symbol diff.c: convert emit_binary_diff_body to use emit_diff_symbol submodule.c: migrate diff output to use emit_diff_symbol diff.c: emit_diff_symbol learns DIFF_SYMBOL_REWRITE_DIFF diff.c: emit_diff_symbol learns about DIFF_SYMBOL_BINARY_FILES diff.c: emit_diff_symbol learns DIFF_SYMBOL_HEADER diff.c: emit_diff_symbol learns DIFF_SYMBOL_FILEPAIR_{PLUS, MINUS} diff.c: emit_diff_symbol learns DIFF_SYMBOL_CONTEXT_INCOMPLETE diff.c: emit_diff_symbol learns DIFF_SYMBOL_WORDS[_PORCELAIN] diff.c: migrate emit_line_checked to use emit_diff_symbol diff.c: emit_diff_symbol learns DIFF_SYMBOL_NO_LF_EOF diff.c: emit_diff_symbol learns DIFF_SYMBOL_CONTEXT_FRAGINFO ...
2017-08-23Merge branch 'ah/doc-wserrorhighlight' into maintLibravatar Junio C Hamano1-9/+8
Doc update. * ah/doc-wserrorhighlight: doc: add missing values "none" and "default" for diff.wsErrorHighlight
2017-08-16diff: define block by number of alphanumeric charsLibravatar Jonathan Tan1-5/+3
The existing behavior of diff --color-moved=zebra does not define the minimum size of a block at all, instead relying on a heuristic applied later to filter out sets of adjacent moved lines that are shorter than 3 lines long. This can be confusing, because a block could thus be colored as moved at the source but not at the destination (or vice versa), depending on its neighbors. Instead, teach diff that the minimum size of a block is 20 alphanumeric characters, the same heuristic used by "git blame". This allows diff to still exclude uninteresting lines appearing on their own (such as those solely consisting of one or a few closing braces), as was the intention of the adjacent-moved-line heuristic. This requires a change in some tests in that some of their lines are no longer considered to be part of a block, because they are too short. Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-11Merge branch 'ah/doc-wserrorhighlight'Libravatar Junio C Hamano1-9/+8
Doc update. * ah/doc-wserrorhighlight: doc: add missing values "none" and "default" for diff.wsErrorHighlight
2017-07-31diff-options doc: grammar fixLibravatar Anthony Sottile1-1/+1
Signed-off-by: Anthony Sottile <asottile@umich.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-25doc: add missing values "none" and "default" for diff.wsErrorHighlightLibravatar Andreas Heiduk1-9/+8
The values have eluded documentation so far. While at it streamline the wording by grouping relevant parts together. Signed-off-by: Andreas Heiduk <asheiduk@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-30diff: document the new --color-moved settingLibravatar Stefan Beller1-0/+36
Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-02Documentation: improve description for core.quotePathLibravatar Andreas Heiduk1-4/+3
Linking the description for pathname quoting to the configuration variable "core.quotePath" removes inconstistent and incomplete sections while also giving two hints how to deal with it: Either with "-c core.quotePath=false" or with "-z". Signed-off-by: Andreas Heiduk <asheiduk@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-23Merge branch 'rh/diff-orderfile-doc'Libravatar Junio C Hamano1-2/+32
Documentation fix. * rh/diff-orderfile-doc: diff: document the format of the -O (diff.orderFile) file diff: document behavior of relative diff.orderFile
2017-01-15diff: document the format of the -O (diff.orderFile) fileLibravatar Richard Hansen1-2/+32
Signed-off-by: Richard Hansen <hansenr@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-12diff: add interhunk context config optionLibravatar Vegard Nossum1-0/+2
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>
2016-10-27Merge branch 'nd/ita-empty-commit'Libravatar Junio C Hamano1-0/+8
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"
2016-10-26Merge branch 'jc/ws-error-highlight'Libravatar Junio C Hamano1-0/+2
"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
2016-10-24diff: add --ita-[in]visible-in-indexLibravatar Nguyễn Thái Ngọc Duy1-0/+8
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>
2016-10-04diff: introduce diff.wsErrorHighlight optionLibravatar Junio C Hamano1-0/+2
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>
2016-09-26Merge branch 'mh/diff-indent-heuristic'Libravatar Junio C Hamano1-6/+1
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
2016-09-19blame: honor the diff heuristic options and configLibravatar Michael Haggerty1-7/+1
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 Haggerty1-4/+5
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>
2016-08-31diff: teach diff to display submodule difference with an inline diffLibravatar Jacob Keller1-7/+10
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>
2016-08-31graph: add support for --line-prefix on all graph-aware outputLibravatar Jacob Keller1-0/+3
Add an extension to git-diff and git-log (and any other graph-aware displayable output) such that "--line-prefix=<string>" will print the additional line-prefix on every line of output. To make this work, we have to fix a few bugs in the graph API that force graph_show_commit_msg to be used only when you have a valid graph. Additionally, we extend the default_diff_output_prefix handler to work even when no graph is enabled. This is somewhat of a hack on top of the graph API, but I think it should be acceptable here. This will be used by a future extension of submodule display which displays the submodule diff as the actual diff between the pre and post commit in the submodule project. Add some tests for both git-log and git-diff to ensure that the prefix is honored correctly. Signed-off-by: Jacob Keller <jacob.keller@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-07-25Merge branch 'jc/doc-diff-filter-exclude'Libravatar Junio C Hamano1-0/+3
Belated doc update for a feature added in v1.8.5. * jc/doc-diff-filter-exclude: diff: document diff-filter exclusion
2016-07-14diff: document diff-filter exclusionLibravatar Junio C Hamano1-0/+3
In v1.8.5 days, 7f2ea5f0 (diff: allow lowercase letter to specify what change class to exclude, 2013-07-17) taught the "--diff-filter" mechanism to take lowercase letters as exclusion, but we forgot to document it. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-10Merge branch 'jk/diff-compact-heuristic'Libravatar Junio C Hamano1-0/+7
It turns out that the earlier effort to update the heuristics may want to use a bit more time to mature. Turn it off by default. * jk/diff-compact-heuristic: diff: disable compaction heuristic for now
2016-06-10diff: disable compaction heuristic for nowLibravatar Junio C Hamano1-0/+7
http://lkml.kernel.org/g/20160610075043.GA13411@sigill.intra.peff.net reports that a change to add a new "function" with common ending with the existing one at the end of the file is shown like this: def foo do_foo_stuff() + common_ending() +end + +def bar + do_bar_stuff() + common_ending() end when the new heuristic is in use. In reality, the change is to add the blank line before "def bar" and everything below, which is what the code without the new heuristic shows. Disable the heuristics by default, and resurrect the documentation for the option and the configuration variables, while clearly marking the feature as still experimental. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-05-09Documentation: fix linkgit referencesLibravatar Junio C Hamano1-1/+1
There are a handful of incorrect "linkgit:<page>[<section>]" instances in our documentation set. * Some have an extra colon after "linkgit:"; fix them by removing the extra colon; * Some refer to a page outside the Git suite, namely curl(1); fix them by using the `curl(1)` that already appears on the same page for the same purpose of referring the readers to its manual page. * Some spell the name of the page incorrectly, e.g. "rev-list" when they mean "git-rev-list"; fix them. * Some list the manual section incorrectly; fix them to make sure they match what is at the top of the target of the link. Signed-off-by: Junio C Hamano <gitster@pobox.com>