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 <gitster@pobox.com>
Junio C Hamano committed
Jul 2, 2012 at 00:54 UTC
b31272f704d03258a90b0e83e0f5c8df5c038ae6
1 file changed
+21
-4
builtin/blame.c
+21
-4
@@ -1828,6 +1828,16 @@ static int read_ancestry(const char *graft_file)
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return 0;
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}
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+static int update_auto_abbrev(int auto_abbrev, struct origin *suspect)
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+{
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+ const char *uniq = find_unique_abbrev(suspect->commit->object.sha1,
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+ auto_abbrev);
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+ int len = strlen(uniq);
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+ if (auto_abbrev < len)
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+ return len;
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+ return auto_abbrev;
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+}
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+
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/*
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* How many columns do we need to show line numbers in decimal?
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*/
@@ -1850,12 +1860,16 @@ static void find_alignment(struct scoreboard *sb, int *option)
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int longest_dst_lines = 0;
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unsigned largest_score = 0;
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struct blame_entry *e;
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+ int compute_auto_abbrev = (abbrev < 0);
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+ int auto_abbrev = default_abbrev;
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for (e = sb->ent; e; e = e->next) {
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struct origin *suspect = e->suspect;
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struct commit_info ci;
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int num;
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+ if (compute_auto_abbrev)
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+ auto_abbrev = update_auto_abbrev(auto_abbrev, suspect);
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if (strcmp(suspect->path, sb->path))
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*option |= OUTPUT_SHOW_NAME;
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num = strlen(suspect->path);
@@ -1883,6 +1897,10 @@ static void find_alignment(struct scoreboard *sb, int *option)
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max_orig_digits = lineno_width(longest_src_lines);
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max_digits = lineno_width(longest_dst_lines);
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max_score_digits = lineno_width(largest_score);
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+
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+ if (compute_auto_abbrev)
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+ /* one more abbrev length is needed for the boundary commit */
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+ abbrev = auto_abbrev + 1;
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}
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/*
@@ -2360,10 +2378,9 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
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parse_done:
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argc = parse_options_end(&ctx);
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- if (abbrev == -1)
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- abbrev = default_abbrev;
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- /* one more abbrev length is needed for the boundary commit */
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- abbrev++;
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+ if (0 < abbrev)
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+ /* one more abbrev length is needed for the boundary commit */
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+ abbrev++;
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if (revs_file && read_ancestry(revs_file))
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die_errno("reading graft file '%s' failed", revs_file);