blame: handle --no-abbrev

You can already ask blame for full sha1s with "-l" or with "--abbrev=40". But for consistency with other parts of Git, we should support "--no-abbrev". Worse, blame already accepts --no-abbrev, but it's totally broken. When we see --no-abbrev, the abbrev variable is set to 0, which is then used as a printf precision. For regular sha1s, that means we print nothing at all (which is very wrong). For boundary commits we decrement it to "-1", which printf interprets as "no limit" (which is almost correct, except it misses the 39-length magic explained in the previous commit). Let's detect --no-abbrev and behave as if --abbrev=40 was given. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jeff King committed Jan 5, 2017 at 23:18 UTC ed58d8088b570e7629bfc94b87e433f05229ef3c
2 files changed +6
builtin/blame.c
+2
@@ -2609,6 +2609,8 @@ parse_done:
2609 if (0 < abbrev && abbrev < GIT_SHA1_HEXSZ)
2610 /* one more abbrev length is needed for the boundary commit */
2611 abbrev++;
2612 + else if (!abbrev)
2613 + abbrev = GIT_SHA1_HEXSZ;
2614
2615 if (revs_file && read_ancestry(revs_file))
2616 die_errno("reading graft file '%s' failed", revs_file);
t/t8002-blame.sh
+4
@@ -114,4 +114,8 @@ test_expect_success 'blame --abbrev=40 behaves like -l' '
114 check_abbrev 39 --abbrev=40 ^HEAD
115 '
116
117 +test_expect_success '--no-abbrev works like --abbrev=40' '
118 + check_abbrev 40 --no-abbrev
119 +'
120 +
121 test_done