xdiff: don't trim common tail with -W

The function trim_common_tail() exits early if context lines are
requested.  If -U0 and -W are specified together then it can still trim
context lines that might belong to a changed function.  As a result
that function is shown incompletely.

Fix that by calling trim_common_tail() only if no function context or
fixed context is requested.  The parameter ctx is no longer needed now;
remove it.

While at it fix an outdated comment as well.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
René Scharfe 2016-05-28 17:04:31 +02:00 коммит произвёл Junio C Hamano
Родитель 9e6a4cfc38
Коммит e0876bca4d
2 изменённых файлов: 5 добавлений и 7 удалений

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@ -145,7 +145,7 @@ test_expect_success ' context includes begin' '
grep "^ .*Begin of first part" long_common_tail.diff
'
test_expect_failure ' context includes end' '
test_expect_success ' context includes end' '
grep "^ .*End of second part" long_common_tail.diff
'

Просмотреть файл

@ -100,9 +100,9 @@ static int xdiff_outf(void *priv_, mmbuffer_t *mb, int nbuf)
/*
* Trim down common substring at the end of the buffers,
* but leave at least ctx lines at the end.
* but end on a complete line.
*/
static void trim_common_tail(mmfile_t *a, mmfile_t *b, long ctx)
static void trim_common_tail(mmfile_t *a, mmfile_t *b)
{
const int blk = 1024;
long trimmed = 0, recovered = 0;
@ -110,9 +110,6 @@ static void trim_common_tail(mmfile_t *a, mmfile_t *b, long ctx)
char *bp = b->ptr + b->size;
long smaller = (a->size < b->size) ? a->size : b->size;
if (ctx)
return;
while (blk + trimmed <= smaller && !memcmp(ap - blk, bp - blk, blk)) {
trimmed += blk;
ap -= blk;
@ -134,7 +131,8 @@ int xdi_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp, xdemitconf_t co
if (mf1->size > MAX_XDIFF_SIZE || mf2->size > MAX_XDIFF_SIZE)
return -1;
trim_common_tail(&a, &b, xecfg->ctxlen);
if (!xecfg->ctxlen && !(xecfg->flags & XDL_EMIT_FUNCCONTEXT))
trim_common_tail(&a, &b);
return xdl_diff(&a, &b, xpp, xecfg, xecb);
}