[PATCH] diff: code clean-up and removal of rename hack.

A new macro, DIFF_PAIR_RENAME(), is introduced to distinguish a
filepair that is a rename/copy (the definition of which is src
and dst are different paths, of course).  This removes the hack
used in the record_rename_pair() to always put a non-zero value
in the score field.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff.c

@@ -796,7 +796,7 @@ static void diff_resolve_rename_copy(void)
 			for (j = 0; j < q->nr; j++) {
 				pp = q->queue[j];
 				if (!strcmp(p->one->path, pp->one->path) &&
-				    pp->score) {
+				    DIFF_PAIR_RENAME(pp)) {
 					/* rename/copy are always valid
 					 * so we do not say DIFF_FILE_VALID()
 					 * on pp->one and pp->two.
@@ -815,7 +815,7 @@ static void diff_resolve_rename_copy(void)
 		 * whose both sides are valid and of the same type, i.e.
 		 * either in-place edit or rename/copy edit.
 		 */
-		else if (p->score) {
+		else if (DIFF_PAIR_RENAME(p)) {
 			if (p->source_stays) {
 				p->status = 'C';
 				continue;
@@ -828,7 +828,7 @@ static void diff_resolve_rename_copy(void)
 				pp = q->queue[j];
 				if (strcmp(pp->one->path, p->one->path))
 					continue; /* not us */
-				if (!pp->score)
+				if (!DIFF_PAIR_RENAME(pp))
 					continue; /* not a rename/copy */
 				/* pp is a rename/copy from the same source */
 				p->status = 'C';

diffcore-rename.c

@@ -207,7 +207,7 @@ static void record_rename_pair(struct diff_queue_struct *renq,
 	fill_filespec(two, dst->sha1, dst->mode);
 
 	dp = diff_queue(renq, one, two);
-	dp->score = score ? : 1; /* make sure it is at least 1 */
+	dp->score = score;
 	dp->source_stays = rename_src[src_index].src_stays;
 	rename_dst[dst_index].pair = dp;
 }

diffcore.h

@@ -39,15 +39,15 @@ extern void diff_free_filespec_data(struct diff_filespec *);
 struct diff_filepair {
 	struct diff_filespec *one;
 	struct diff_filespec *two;
-	unsigned short int score; /* only valid when one and two are
-				   * different paths
-				   */
+	unsigned short int score;
 	char source_stays; /* all of R/C are copies */
 	char status; /* M C R N D U (see Documentation/diff-format.txt) */
 };
 #define DIFF_PAIR_UNMERGED(p) \
 	(!DIFF_FILE_VALID((p)->one) && !DIFF_FILE_VALID((p)->two))
 
+#define DIFF_PAIR_RENAME(p) (strcmp((p)->one->path, (p)->two->path))
+
 #define DIFF_PAIR_TYPE_CHANGED(p) \
 	((S_IFMT & (p)->one->mode) != (S_IFMT & (p)->two->mode))