Re: git blame gives an ambiguous short revision
From: Junio C Hamano <hidden>
Date: 2016-06-15 22:54:12
Subsystem:
the rest · Maintainer:
Linus Torvalds
Possibly related (same subject, not in this thread)
- 2016-06-15 · git blame gives an ambiguous short revision · Julia Lawall <hidden>
- 2016-06-15 · Re: git blame gives an ambiguous short revision · Julia Lawall <hidden>
- 2016-06-15 · Re: git blame gives an ambiguous short revision · Junio C Hamano <hidden>
- 2016-06-15 · Re: git blame gives an ambiguous short revision · Junio C Hamano <hidden>
Junio C Hamano [off-list ref] writes:
Something like this, perhaps, but I didn't test the patch beyond "it compiles".
OK, now I tested it ;-) I'll queue this and eventually merge down
to older maintenance releases.
-- >8 --
Subject: [PATCH] blame: compute abbreviation width that ensures uniqueness
Julia Lawall noticed that in linux-next repository the commit object
60d5c9f5 (shown with the default abbreviation width baked into "git
blame") in output from
$ git blame -L 3675,3675 60d5c9f5b -- \
drivers/staging/brcm80211/brcmfmac/wl_iw.c
is no longer unique in the repository, which results in "short SHA1
60d5c9f5 is ambiguous".
Compute the minimum abbreviation width that ensures uniqueness when
the user did not specify the --abbrev option to avoid this.
Signed-off-by: Junio C Hamano <redacted>
---
Incidentally, "git show v2.6.39-rc4-181-g60d5c9f5" is resolved
correctly with the recent "prolong the shelf-life of decribed name"
topic that will hopefully be ready by the next release, and it
resolves even shorter "v2.6.39-rc4-181-g60d5c" just fine ;-).
builtin/blame.c | 25 +++++++++++++++++++++----
1 file changed, 21 insertions(+), 4 deletions(-)
diff --git a/builtin/blame.c b/builtin/blame.c
index 3e1f7e1..f13ec32 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c@@ -1828,6 +1828,16 @@ static int read_ancestry(const char *graft_file) return 0; } +static int update_auto_abbrev(int auto_abbrev, struct origin *suspect) +{ + const char *uniq = find_unique_abbrev(suspect->commit->object.sha1, + auto_abbrev); + int len = strlen(uniq); + if (auto_abbrev < len) + return len; + return auto_abbrev; +} + /* * How many columns do we need to show line numbers in decimal? */
@@ -1850,12 +1860,16 @@ static void find_alignment(struct scoreboard *sb, int *option) int longest_dst_lines = 0; unsigned largest_score = 0; struct blame_entry *e; + int compute_auto_abbrev = (abbrev < 0); + int auto_abbrev = default_abbrev; for (e = sb->ent; e; e = e->next) { struct origin *suspect = e->suspect; struct commit_info ci; int num; + if (compute_auto_abbrev) + auto_abbrev = update_auto_abbrev(auto_abbrev, suspect); if (strcmp(suspect->path, sb->path)) *option |= OUTPUT_SHOW_NAME; num = strlen(suspect->path);
@@ -1883,6 +1897,10 @@ static void find_alignment(struct scoreboard *sb, int *option) max_orig_digits = lineno_width(longest_src_lines); max_digits = lineno_width(longest_dst_lines); max_score_digits = lineno_width(largest_score); + + if (compute_auto_abbrev) + /* one more abbrev length is needed for the boundary commit */ + abbrev = auto_abbrev + 1; } /*
@@ -2360,10 +2378,9 @@ int cmd_blame(int argc, const char **argv, const char *prefix) parse_done: argc = parse_options_end(&ctx); - if (abbrev == -1) - abbrev = default_abbrev; - /* one more abbrev length is needed for the boundary commit */ - abbrev++; + if (0 < abbrev) + /* one more abbrev length is needed for the boundary commit */ + abbrev++; if (revs_file && read_ancestry(revs_file)) die_errno("reading graft file '%s' failed", revs_file);
--
1.7.11.1.212.g52fe12e