Merge branch 'lt/diff-tree'

* lt/diff-tree:
  combine-diff: Record diff status a bit more faithfully
  find_unique_abbrev() simplification.

combine-diff.c

@@ -39,6 +39,7 @@ static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr,
 			p->mode = q->queue[i]->two->mode;
 			memcpy(p->parent[n].sha1, q->queue[i]->one->sha1, 20);
 			p->parent[n].mode = q->queue[i]->one->mode;
+			p->parent[n].status = q->queue[i]->status;
 			*tail = p;
 			tail = &p->next;
 		}
@@ -62,6 +63,7 @@ static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr,
 				memcpy(p->parent[n].sha1,
 				       q->queue[i]->one->sha1, 20);
 				p->parent[n].mode = q->queue[i]->one->mode;
+				p->parent[n].status = q->queue[i]->status;
 				break;
 			}
 		}
@@ -716,10 +718,7 @@ static int show_patch_diff(struct combine_diff_path *elem, int num_parent,
 
 	if (show_hunks || mode_differs) {
 		const char *abb;
-		char null_abb[DEFAULT_ABBREV + 1];
 
-		memset(null_abb, '0', DEFAULT_ABBREV);
-		null_abb[DEFAULT_ABBREV] = 0;
 		if (header) {
 			shown_header++;
 			puts(header);
@@ -734,26 +733,33 @@ static int show_patch_diff(struct combine_diff_path *elem, int num_parent,
 		for (i = 0; i < num_parent; i++) {
 			if (elem->parent[i].mode != elem->mode)
 				mode_differs = 1;
-			if (memcmp(elem->parent[i].sha1, null_sha1, 20))
-				abb = find_unique_abbrev(elem->parent[i].sha1,
-							 DEFAULT_ABBREV);
-			else
-				abb = null_abb;
+			abb = find_unique_abbrev(elem->parent[i].sha1,
+						 DEFAULT_ABBREV);
 			printf("%s%s", i ? "," : "", abb);
 		}
-		if (memcmp(elem->sha1, null_sha1, 20))
-			abb = find_unique_abbrev(elem->sha1, DEFAULT_ABBREV);
-		else
-			abb = null_abb;
+		abb = find_unique_abbrev(elem->sha1, DEFAULT_ABBREV);
 		printf("..%s\n", abb);
 
 		if (mode_differs) {
-			printf("mode ");
-			for (i = 0; i < num_parent; i++) {
-				printf("%s%06o", i ? "," : "",
-				       elem->parent[i].mode);
+			int added = !!elem->mode;
+			for (i = 0; added && i < num_parent; i++)
+				if (elem->parent[i].status !=
+				    DIFF_STATUS_ADDED)
+					added = 0;
+			if (added)
+				printf("new file mode %06o", elem->mode);
+			else {
+				if (!elem->mode)
+					printf("deleted file ");
+				printf("mode ");
+				for (i = 0; i < num_parent; i++) {
+					printf("%s%06o", i ? "," : "",
+					       elem->parent[i].mode);
+				}
+				if (elem->mode)
+					printf("..%06o", elem->mode);
 			}
-			printf("..%06o\n", elem->mode);
+			putchar('\n');
 		}
 		dump_sline(sline, cnt, num_parent);
 	}
@@ -820,8 +826,11 @@ static void show_raw_diff(struct combine_diff_path *p, int num_parent, const cha
 	}
 
 	if (opt->output_format == DIFF_FORMAT_RAW ||
-	    opt->output_format == DIFF_FORMAT_NAME_STATUS)
-		printf("%c%c", mod_type, inter_name_termination);
+	    opt->output_format == DIFF_FORMAT_NAME_STATUS) {
+		for (i = 0; i < num_parent; i++)
+			putchar(p->parent[i].status);
+		putchar(inter_name_termination);
+	}
 
 	if (line_termination) {
 		if (quote_c_style(p->path, NULL, NULL, 0))

diff.c

@@ -963,7 +963,7 @@ void diff_free_filepair(struct diff_filepair *p)
 }
 
 /* This is different from find_unique_abbrev() in that
- * it needs to deal with 0{40} SHA1.
+ * it stuffs the result with dots for alignment.
  */
 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
 {
@@ -973,16 +973,8 @@ const char *diff_unique_abbrev(const unsigned char *sha1, int len)
 		return sha1_to_hex(sha1);
 
 	abbrev = find_unique_abbrev(sha1, len);
-	if (!abbrev) {
-		if (!memcmp(sha1, null_sha1, 20)) {
-			char *buf = sha1_to_hex(null_sha1);
-			if (len < 37)
-				strcpy(buf + len, "...");
-			return buf;
-		}
-		else 
-			return sha1_to_hex(sha1);
-	}
+	if (!abbrev)
+		return sha1_to_hex(sha1);
 	abblen = strlen(abbrev);
 	if (abblen < 37) {
 		static char hex[41];

diff.h

@@ -66,6 +66,7 @@ struct combine_diff_path {
 	unsigned int mode;
 	unsigned char sha1[20];
 	struct combine_diff_parent {
+		char status;
 		unsigned int mode;
 		unsigned char sha1[20];
 	} parent[FLEX_ARRAY];

sha1_name.c

@@ -186,16 +186,18 @@ static int get_short_sha1(const char *name, int len, unsigned char *sha1,
 
 const char *find_unique_abbrev(const unsigned char *sha1, int len)
 {
-	int status;
+	int status, is_null;
 	static char hex[41];
 
+	is_null = !memcmp(sha1, null_sha1, 20);
 	memcpy(hex, sha1_to_hex(sha1), 40);
 	if (len == 40)
 		return hex;
 	while (len < 40) {
 		unsigned char sha1_ret[20];
 		status = get_short_sha1(hex, len, sha1_ret, 1);
-		if (!status) {
+		if (!status ||
+		    (is_null && status != SHORT_NAME_AMBIGUOUS)) {
 			hex[len] = 0;
 			return hex;
 		}