tests: introduce test_must_fail

diff --git a/builtin-describe.c b/builtin-describe.c
index 3428483134156f4e1761aa47ed2e8098a294808c..05e309f5ad15f9a6f85df34322bb59152b4e37be 100644 (file)
--- a/builtin-describe.c
+++ b/builtin-describe.c
@@ -46,19 +46,34 @@ static void add_to_known_names(const char *path,
 
 static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 {
-       struct commit *commit = lookup_commit_reference_gently(sha1, 1);
+       int might_be_tag = !prefixcmp(path, "refs/tags/");
+       struct commit *commit;
        struct object *object;
-       int prio;
+       unsigned char peeled[20];
+       int is_tag, prio;
 
-       if (!commit)
+       if (!all && !might_be_tag)
                return 0;
-       object = parse_object(sha1);
+
+       if (!peel_ref(path, peeled) && !is_null_sha1(peeled)) {
+               commit = lookup_commit_reference_gently(peeled, 1);
+               if (!commit)
+                       return 0;
+               is_tag = !!hashcmp(sha1, commit->object.sha1);
+       } else {
+               commit = lookup_commit_reference_gently(sha1, 1);
+               object = parse_object(sha1);
+               if (!commit || !object)
+                       return 0;
+               is_tag = object->type == OBJ_TAG;
+       }
+
        /* If --all, then any refs are used.
         * If --tags, then any tags are used.
         * Otherwise only annotated tags are used.
         */
-       if (!prefixcmp(path, "refs/tags/")) {
-               if (object->type == OBJ_TAG) {
+       if (might_be_tag) {
+               if (is_tag) {
                        prio = 2;
                        if (pattern && fnmatch(pattern, path + 10, 0))
                                prio = 0;
@@ -159,6 +174,8 @@ static void describe(const char *arg, int last_one)
                return;
        }
 
+       if (!max_candidates)
+               die("no tag exactly matches '%s'", sha1_to_hex(cmit->object.sha1));
        if (debug)
                fprintf(stderr, "searching to describe %s\n", arg);
 
@@ -255,6 +272,8 @@ int cmd_describe(int argc, const char **argv, const char *prefix)
                OPT_BOOLEAN(0, "all",        &all, "use any ref in .git/refs"),
                OPT_BOOLEAN(0, "tags",       &tags, "use any tag in .git/refs/tags"),
                OPT__ABBREV(&abbrev),
+               OPT_SET_INT(0, "exact-match", &max_candidates,
+                           "only output exact matches", 0),
                OPT_INTEGER(0, "candidates", &max_candidates,
                            "consider <n> most recent tags (default: 10)"),
                OPT_STRING(0, "match",       &pattern, "pattern",
@@ -263,8 +282,8 @@ int cmd_describe(int argc, const char **argv, const char *prefix)
        };
 
        argc = parse_options(argc, argv, options, describe_usage, 0);
-       if (max_candidates < 1)
-               max_candidates = 1;
+       if (max_candidates < 0)
+               max_candidates = 0;
        else if (max_candidates > MAX_TAGS)
                max_candidates = MAX_TAGS;