xdl_merge(): add optional ancestor label to diff3-style output

The ‘git checkout --conflict=diff3’ command can be used to
present conflicts hunks including text from the common ancestor:

	<<<<<<< ours
	ourside
	|||||||
	original
	=======
	theirside
	>>>>>>> theirs

The added information is helpful for resolving merges by hand, and
merge tools can usually grok it because it is very similar to the
output from diff3 -m.

A subtle change can help more tools to understand the output.  ‘diff3’
includes the name of the merge base on the ||||||| line of the output,
and some tools misparse the conflict hunks without it.  Add a new
xmp->ancestor parameter to xdl_merge() for use with conflict style
XDL_MERGE_DIFF3 as a label on the ||||||| line for any conflict hunks.

If xmp->ancestor is NULL, the output format is unchanged.  Thus, this
change only provides unexposed plumbing for the new feature; it does
not affect the outward behavior of git.

Requested-by: Stefan Monnier <monnier@iro.umontreal.ca>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Bert Wesarg <Bert.Wesarg@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Jonathan Nieder 2010-03-20 19:31:44 -05:00 committed by Junio C Hamano
parent 6a843348ab
commit 8a161433a0
2 changed files with 15 additions and 2 deletions

View File

@ -117,6 +117,7 @@ typedef struct s_xmparam {
int level;
int favor;
int style;
const char *ancestor; /* label for orig */
} xmparam_t;
#define DEFAULT_CONFLICT_MARKER_SIZE 7

View File

@ -145,11 +145,13 @@ static int xdl_orig_copy(xdfenv_t *xe, int i, int count, int add_nl, char *dest)
static int fill_conflict_hunk(xdfenv_t *xe1, const char *name1,
xdfenv_t *xe2, const char *name2,
const char *name3,
int size, int i, int style,
xdmerge_t *m, char *dest, int marker_size)
{
int marker1_size = (name1 ? strlen(name1) + 1 : 0);
int marker2_size = (name2 ? strlen(name2) + 1 : 0);
int marker3_size = (name3 ? strlen(name3) + 1 : 0);
int j;
if (marker_size <= 0)
@ -179,10 +181,15 @@ static int fill_conflict_hunk(xdfenv_t *xe1, const char *name1,
if (style == XDL_MERGE_DIFF3) {
/* Shared preimage */
if (!dest) {
size += marker_size + 1;
size += marker_size + 1 + marker3_size;
} else {
for (j = 0; j < marker_size; j++)
dest[size++] = '|';
if (marker3_size) {
dest[size] = ' ';
memcpy(dest + size + 1, name3, marker3_size - 1);
size += marker3_size;
}
dest[size++] = '\n';
}
size += xdl_orig_copy(xe1, m->i0, m->chg0, 1,
@ -217,6 +224,7 @@ static int fill_conflict_hunk(xdfenv_t *xe1, const char *name1,
static int xdl_fill_merge_buffer(xdfenv_t *xe1, const char *name1,
xdfenv_t *xe2, const char *name2,
const char *ancestor_name,
int favor,
xdmerge_t *m, char *dest, int style,
int marker_size)
@ -229,6 +237,7 @@ static int xdl_fill_merge_buffer(xdfenv_t *xe1, const char *name1,
if (m->mode == 0)
size = fill_conflict_hunk(xe1, name1, xe2, name2,
ancestor_name,
size, i, style, m, dest,
marker_size);
else if (m->mode & 3) {
@ -403,6 +412,7 @@ static int xdl_do_merge(xdfenv_t *xe1, xdchange_t *xscr1, const char *name1,
xmparam_t const *xmp, mmbuffer_t *result) {
xdmerge_t *changes, *c;
xpparam_t const *xpp = &xmp->xpp;
const char *const ancestor_name = xmp->ancestor;
int i0, i1, i2, chg0, chg1, chg2;
int level = xmp->level;
int style = xmp->style;
@ -540,6 +550,7 @@ static int xdl_do_merge(xdfenv_t *xe1, xdchange_t *xscr1, const char *name1,
if (result) {
int marker_size = xmp->marker_size;
int size = xdl_fill_merge_buffer(xe1, name1, xe2, name2,
ancestor_name,
favor, changes, NULL, style,
marker_size);
result->ptr = xdl_malloc(size);
@ -548,7 +559,8 @@ static int xdl_do_merge(xdfenv_t *xe1, xdchange_t *xscr1, const char *name1,
return -1;
}
result->size = size;
xdl_fill_merge_buffer(xe1, name1, xe2, name2, favor, changes,
xdl_fill_merge_buffer(xe1, name1, xe2, name2,
ancestor_name, favor, changes,
result->ptr, style, marker_size);
}
return xdl_cleanup_merge(changes);