[PATCH] Show dissimilarity index for D and N case.

The way broken deletes and creates are shown in the -p
(diff-patch) output format has become consistent with how
rename/copy edits are shown.  They will show "dissimilarity
index" value, immediately following the "deleted file mode" and
"new file mode" lines.

The git-apply is taught to grok such an extended header.

Signed-off-by: Junio C Hamano <junkio@cox.net>

2 files changed, 24 insertions, 2 deletions

diff --git a/apply.c b/apply.c
index 3160207..74908cd 100644
--- a/apply.c
+++ b/apply.c
@@ -336,6 +336,11 @@ static int gitdiff_similarity(const char *line, struct patch *patch)
 	return 0;
 }
 
+static int gitdiff_dissimilarity(const char *line, struct patch *patch)
+{
+	return 0;
+}
+
 /*
  * This is normal for a diff that doesn't change anything: we'll fall through
  * into the next diff. Tell the parser to break out.
@@ -437,6 +442,7 @@ static int parse_git_header(char *line, int len, unsigned int size, struct patch
 			{ "rename from ", gitdiff_renamesrc },
 			{ "rename to ", gitdiff_renamedst },
 			{ "similarity index ", gitdiff_similarity },
+			{ "dissimilarity index ", gitdiff_dissimilarity },
 			{ "", gitdiff_unrecognized },
 		};
 		int i;
diff --git a/diff.c b/diff.c
index d5881c7..d7cde8f 100644
--- a/diff.c
+++ b/diff.c
@@ -132,10 +132,16 @@ static void builtin_diff(const char *name_a,
 			    diff_arg, input_name_sq[0], input_name_sq[1]);
 
 	printf("diff --git a/%s b/%s\n", name_a, name_b);
-	if (!path1[0][0])
+	if (!path1[0][0]) {
 		printf("new file mode %s\n", temp[1].mode);
-	else if (!path1[1][0])
+		if (xfrm_msg && xfrm_msg[0])
+			puts(xfrm_msg);
+	}
+	else if (!path1[1][0]) {
 		printf("deleted file mode %s\n", temp[0].mode);
+		if (xfrm_msg && xfrm_msg[0])
+			puts(xfrm_msg);
+	}
 	else {
 		if (strcmp(temp[0].mode, temp[1].mode)) {
 			printf("old mode %s\n", temp[0].mode);
@@ -733,6 +739,16 @@ static void diff_flush_patch(struct diff_filepair *p)
 			p->one->path, p->two->path);
 		msg = msg_;
 		break;
+	case 'D': case 'N':
+		if (DIFF_PAIR_BROKEN(p)) {
+			sprintf(msg_,
+				"dissimilarity index %d%%",
+				(int)(0.5 + p->score * 100.0/MAX_SCORE));
+			msg = msg_;
+		}
+		else
+			msg = NULL;
+		break;
 	default:
 		msg = NULL;
 	}