describe: when failing, tell the user about options that work

diff --git a/builtin-describe.c b/builtin-describe.c
index 7a662980d102a275fceb8299bba0b84b41a8f9cb..504d9b120976e7d65d4a229b251e1a006c69e715 100644 (file)
--- a/builtin-describe.c
+++ b/builtin-describe.c
@@ -20,6 +20,7 @@ static int tags;      /* Allow lightweight tags */
 static int longformat;
 static int abbrev = DEFAULT_ABBREV;
 static int max_candidates = 10;
+static int found_names;
 static const char *pattern;
 static int always;
 
@@ -49,6 +50,7 @@ static void add_to_known_names(const char *path,
                memcpy(e->path, path, len);
                commit->util = e;
        }
+       found_names = 1;
 }
 
 static int get_name(const char *path, const unsigned char *sha1, int flag, void *cb_data)
@@ -94,8 +96,6 @@ static int get_name(const char *path, const unsigned char *sha1, int flag, void
        if (!all) {
                if (!prio)
                        return 0;
-               if (!tags && prio < 2)
-                       return 0;
        }
        add_to_known_names(all ? path + 5 : path + 10, commit, prio, sha1);
        return 0;
@@ -178,11 +178,11 @@ static void describe(const char *arg, int last_one)
        unsigned char sha1[20];
        struct commit *cmit, *gave_up_on = NULL;
        struct commit_list *list;
-       static int initialized = 0;
        struct commit_name *n;
        struct possible_tag all_matches[MAX_TAGS];
        unsigned int match_cnt = 0, annotated_cnt = 0, cur_match;
        unsigned long seen_commits = 0;
+       unsigned int unannotated_cnt = 0;
 
        if (get_sha1(arg, sha1))
                die("Not a valid object name %s", arg);
@@ -190,11 +190,6 @@ static void describe(const char *arg, int last_one)
        if (!cmit)
                die("%s is not a valid '%s' object", arg, commit_type);
 
-       if (!initialized) {
-               initialized = 1;
-               for_each_ref(get_name, NULL);
-       }
-
        n = cmit->util;
        if (n) {
                /*
@@ -221,7 +216,9 @@ static void describe(const char *arg, int last_one)
                seen_commits++;
                n = c->util;
                if (n) {
-                       if (match_cnt < max_candidates) {
+                       if (!tags && !all && n->prio < 2) {
+                               unannotated_cnt++;
+                       } else if (match_cnt < max_candidates) {
                                struct possible_tag *t = &all_matches[match_cnt++];
                                t->name = n;
                                t->depth = seen_commits - 1;
@@ -263,7 +260,14 @@ static void describe(const char *arg, int last_one)
                        printf("%s\n", find_unique_abbrev(sha1, abbrev));
                        return;
                }
-               die("cannot describe '%s'", sha1_to_hex(sha1));
+               if (unannotated_cnt)
+                       die("No annotated tags can describe '%s'.\n"
+                           "However, there were unannotated tags: try --tags.",
+                           sha1_to_hex(sha1));
+               else
+                       die("No tags can describe '%s'.\n"
+                           "Try --always, or create some tags.",
+                           sha1_to_hex(sha1));
        }
 
        qsort(all_matches, match_cnt, sizeof(all_matches[0]), compare_pt);
@@ -354,6 +358,10 @@ int cmd_describe(int argc, const char **argv, const char *prefix)
                return cmd_name_rev(i + argc, args, prefix);
        }
 
+       for_each_ref(get_name, NULL);
+       if (!found_names && !always)
+               die("No names found, cannot describe anything.");
+
        if (argc == 0) {
                describe("HEAD", 1);
        } else {