From 15af58c1adba431c216e2a45fa0d22944560ba02 Mon Sep 17 00:00:00 2001 From: Stefan Beller Date: Thu, 4 Jan 2018 14:50:42 -0800 Subject: diffcore: add a pickaxe option to find a specific blob 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 ` gives a description as ':'. 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 Signed-off-by: Junio C Hamano --- Documentation/diff-options.txt | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'Documentation') diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt index dd0dba5b1d..f9cf85db05 100644 --- a/Documentation/diff-options.txt +++ b/Documentation/diff-options.txt @@ -492,6 +492,15 @@ occurrences of that string did not change). See the 'pickaxe' entry in linkgit:gitdiffcore[7] for more information. +--find-object=:: + Look for differences that change the number of occurrences of + the specified object. Similar to `-S`, just the argument is different + in that it doesn't search for a specific string but for a specific + object id. ++ +The object can be a blob or a submodule commit. It implies the `-t` option in +`git-log` to also find trees. + --pickaxe-all:: When `-S` or `-G` finds a change, show all the changes in that changeset, not just the files that contain the change @@ -500,6 +509,7 @@ information. --pickaxe-regex:: Treat the given to `-S` as an extended POSIX regular expression to match. + endif::git-format-patch[] -O:: -- cgit v1.2.3