diff: Fix rename pretty-print when suffix and prefix overlap

When considering a rename for two files that have a suffix and a prefix
that can overlap, a confusing line is shown. As an example, renaming
"a/b/b/c" to "a/b/c" shows "a/b/{ => }/b/c".

Currently, what we do is calculate the common prefix ("a/b/"), and the
common suffix ("/b/c"), but the same "/b/" is actually counted both in
prefix and suffix. Then when calculating the size of the non-common part,
we end-up with a negative value which is reset to 0, thus the "{ => }".

Do not allow the common suffix to overlap the common prefix and stop
when reaching a "/" that would be in both.

Signed-off-by: Antoine Pelisse <apelisse@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Antoine Pelisse 2013-02-23 17:48:45 +01:00 committed by Junio C Hamano
parent f174a2583c
commit d020e27fda

11
diff.c
View file

@ -1177,7 +1177,16 @@ static char *pprint_rename(const char *a, const char *b)
old = a + len_a;
new = b + len_b;
sfx_length = 0;
while (a <= old && b <= new && *old == *new) {
/*
* Note:
* if pfx_length is 0, old/new will never reach a - 1 because it
* would mean the whole string is common suffix. But then, the
* whole string would also be a common prefix, and we would not
* have pfx_length equals 0.
*/
while (a + pfx_length - 1 <= old &&
b + pfx_length - 1 <= new &&
*old == *new) {
if (*old == '/')
sfx_length = len_a - (old - a);
old--;