[1/2] replaces "pickaxe regex" with "regex", as suggested by Junio.
[2/2] is now co-authored by Junio. I've taken what I think are the best changes introduced by both versions and merged them. The inter-diff follows. diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt index b61a666..2835eef 100644 --- a/Documentation/diff-options.txt +++ b/Documentation/diff-options.txt @@ -383,18 +383,19 @@ ifndef::git-format-patch that matches other criteria, nothing is selected. -S<string>:: - Look for commits that change the number of occurrences of the - specified string (i.e. addition/ deletion) in a file. + Look for differences that change the number of occurrences of + the specified string (i.e. addition/deletion) in a file. Intended for the scripter's use. + It is especially useful when you're looking for an exact block of code (like a struct), and want to know the history of that block since it -first came into being. +first came into being: use the feature iteratively to feed the +interesting block in the preimage back into `-S`, and keep going until +you get the very first version of the block. -G<regex>:: - Grep through the patch text of commits for added/removed lines - that match <regex>. `--pickaxe-regex` is implied in this - mode. + Look for differences whose patch text contains added/removed + lines that match <regex>. + To illustrate the difference between `-S<regex> --pickaxe-regex` and `-G<regex>`, consider a commit with the following diff in the same @@ -408,7 +409,7 @@ file: + While `git log -G"regexec\(regexp"` will show this commit, `git log -S"regexec\(regexp" --pickaxe-regex` will not (because the number of -occurrences of that string didn't change). +occurrences of that string did not change). + See the 'pickaxe' entry in linkgit:gitdiffcore for more information. @@ -419,8 +420,8 @@ information. in <string>. --pickaxe-regex:: - Treat the <string> not as a plain string, but an extended - POSIX regex to match. It is implied when `-G` is used. + Treat the <string> given to `-S` as an extended POSIX regular + expression to match. endif::git-format-patch -O<orderfile>:: diff --git a/Documentation/gitdiffcore.txt b/Documentation/gitdiffcore.txt index d0f2b91..ef4c04a 100644 --- a/Documentation/gitdiffcore.txt +++ b/Documentation/gitdiffcore.txt @@ -225,31 +225,29 @@ diffcore-pickaxe: For Detecting Addition/Deletion of Specified String There are two kinds of pickaxe: the S kind (corresponding to 'git log -S') and the G kind (mnemonic: grep; corresponding to 'git log -G'). -The S kind detects filepairs whose "result" side and "origin" side -have different number of occurrences of specified string. By -definition, it will not detect in-file moves. Also, when a commit -moves a file wholesale without affecting the string being looked at, -rename detection kicks in as usual, and 'git log -S' omits the commit -(since the number of occurrences of that string didn't change in that -rename-detected filepair). The implementation essentially runs a -count, and is significantly cheaper than the G kind. - -The G kind detects filepairs whose patch text has an added or a -deleted line that matches the given regexp. This means that it can -detect in-file (or what rename-detection considers the same file) -moves. The implementation of 'git log -G' runs diff twice and greps, -and this can be quite expensive. - -When `--pickaxe-regex` is used with `-S`, treat the <string> not as a -plain string, but an extended POSIX regex to match. It is implied -when `-G` is used. - -When `--pickaxe-all` is not in effect, diffcore-pickaxe leaves only -the filepairs that touch the specified string in its output. When in -effect, diffcore-pickaxe leaves all filepairs intact if there is such -a filepair, or makes the output empty otherwise. The latter behavior -is designed to make reviewing of the changes in the context of the -whole changeset easier. +"-S<block of text>" detects filepairs whose preimage and postimage +have different number of occurrences of the specified block of text. +By definition, it will not detect in-file moves. Also, when a +changeset moves a file wholesale without affecting the interesting +string, rename detection kicks in as usual, and `-S` omits the +filepair (since the number of occurrences of that string didn't change +in that rename-detected filepair). The implementation essentially +runs a count, and is significantly cheaper than the G kind. When used +with `--pickaxe-regex`, treat the <block of text> as an extended POSIX +regular expression to match, instead of a literal string. + +"-G<regular expression>" detects filepairs whose textual diff has an +added or a deleted line that matches the given regular expression. +This means that it can detect in-file (or what rename-detection +considers the same file) moves. The implementation runs diff twice +and greps, and this can be quite expensive. + +When `-S` or `-G` are used without `--pickaxe-all`, only filepairs +that match their respective criterion are kept in the output. When +`--pickaxe-all` is used, if even one filepair matches their respective +criterion in a changeset, the entire changeset is kept. This behavior +is designed to make reviewing changes in the context of the whole +changeset easier. diffcore-order: For Sorting the Output Based on Filenames --------------------------------------------------------- Ramkumar Ramachandra (2): diffcore-pickaxe: make error messages more consistent diffcore-pickaxe doc: document -S and -G properly Documentation/diff-options.txt | 38 +++++++++++++++++++++++++++++-------- Documentation/gitdiffcore.txt | 43 ++++++++++++++++++++++++------------------ diffcore-pickaxe.c | 4 ++-- 3 files changed, 57 insertions(+), 28 deletions(-) -- 1.8.3.rc3.17.gd95ec6c.dirty -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html