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@xxxxxxxx>
---
Noticed while digging on the nearby thread:
http://public-inbox.org/git/20170227090233.uk7dfruggytgmuw2@xxxxxxxxxxxxxxxxxxxxx/
sha1_name.c | 3 ++-
t/t0100-previous.sh | 8 ++++++++
2 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/sha1_name.c b/sha1_name.c
index 73a915ff1..9b5d14b4b 100644
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -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) {
diff --git a/t/t0100-previous.sh b/t/t0100-previous.sh
index e0a694023..58c0b7e9b 100755
--- a/t/t0100-previous.sh
+++ b/t/t0100-previous.sh
@@ -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
--
2.12.0.624.gbb1b07a2c