interpret_branch_name(): handle auto-namelen for @{-1}

The interpret_branch_name() function takes a ptr/len pair
for the name, but you can pass "0" for "namelen", which will
cause it to check the length with strlen().

However, before we do that auto-namelen magic, we call
interpret_nth_prior_checkout(), which gets fed the bogus
"0". This was broken by 8cd4249c4 (interpret_branch_name:
always respect "namelen" parameter, 2014-01-15).  Though to
be fair to that commit, it was broken in the _opposite_
direction before, where we would always treat "name" as a
string even if a length was passed.

You can see the bug with "git log -g @{-1}". That code path
always passes "0", and without this patch it cannot figure
out which branch's reflog to show.

We can fix it by a small reordering of the code.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Jeff King 2017-02-27 04:25:40 -05:00 committed by Junio C Hamano
parent 3b9e3c2ced
commit 13228c30a6
2 changed files with 10 additions and 1 deletions

View File

@ -1263,11 +1263,12 @@ int interpret_branch_name(const char *name, int namelen, struct strbuf *buf)
{
char *at;
const char *start;
int len = interpret_nth_prior_checkout(name, namelen, buf);
int len;
if (!namelen)
namelen = strlen(name);
len = interpret_nth_prior_checkout(name, namelen, buf);
if (!len) {
return len; /* syntax Ok, not enough switches */
} else if (len > 0) {

View File

@ -56,5 +56,13 @@ test_expect_success 'merge @{-100} before checking out that many branches yet' '
test_must_fail git merge @{-100}
'
test_expect_success 'log -g @{-1}' '
git checkout -b last_branch &&
git checkout -b new_branch &&
echo "last_branch@{0}" >expect &&
git log -g --format=%gd @{-1} >actual &&
test_cmp expect actual
'
test_done