[PATCH] Add -B flag to diff-* brothers.
A new diffcore transformation, diffcore-break.c, is introduced.
When the -B flag is given, a patch that represents a complete
rewrite is broken into a deletion followed by a creation. This
makes it easier to review such a complete rewrite patch.
The -B flag takes the same syntax as the -M and -C flags to
specify the minimum amount of non-source material the resulting
file needs to have to be considered a complete rewrite, and
defaults to 99% if not specified.
As the new test t4008-diff-break-rewrite.sh demonstrates, if a
file is a complete rewrite, it is broken into a delete/create
pair, which can further be subjected to the usual rename
detection if -M or -C is used. For example, if file0 gets
completely rewritten to make it as if it were rather based on
file1 which itself disappeared, the following happens:
The original change looks like this:
file0 --> file0' (quite different from file0)
file1 --> /dev/null
After diffcore-break runs, it would become this:
file0 --> /dev/null
/dev/null --> file0'
file1 --> /dev/null
Then diffcore-rename matches them up:
file1 --> file0'
The internal score values are finer grained now. Earlier
maximum of 10000 has been raised to 60000; there is no user
visible changes but there is no reason to waste available bits.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/diff.c b/diff.c
index a080d94..38a1bab 100644
--- a/diff.c
+++ b/diff.c
@@ -603,6 +603,7 @@
dp->two = two;
dp->score = 0;
dp->source_stays = 0;
+ dp->broken_pair = 0;
diff_q(queue, dp);
return dp;
}
@@ -637,6 +638,16 @@
sprintf(status, "%c%03d", p->status,
(int)(0.5 + p->score * 100.0/MAX_SCORE));
break;
+ case 'N': case 'D':
+ two_paths = 0;
+ if (p->score)
+ sprintf(status, "%c%03d", p->status,
+ (int)(0.5 + p->score * 100.0/MAX_SCORE));
+ else {
+ status[0] = p->status;
+ status[1] = 0;
+ }
+ break;
default:
two_paths = 0;
status[0] = p->status;
@@ -760,8 +771,9 @@
{
diff_debug_filespec(p->one, i, "one");
diff_debug_filespec(p->two, i, "two");
- fprintf(stderr, "score %d, status %c source_stays %d\n",
- p->score, p->status ? : '?', p->source_stays);
+ fprintf(stderr, "score %d, status %c stays %d broken %d\n",
+ p->score, p->status ? : '?',
+ p->source_stays, p->broken_pair);
}
void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
@@ -875,10 +887,13 @@
void diffcore_std(const char **paths,
int detect_rename, int rename_score,
- const char *pickaxe, int pickaxe_opts)
+ const char *pickaxe, int pickaxe_opts,
+ int break_opt)
{
if (paths && paths[0])
diffcore_pathspec(paths);
+ if (0 <= break_opt)
+ diffcore_break(break_opt);
if (detect_rename)
diffcore_rename(detect_rename, rename_score);
if (pickaxe)
