check-ref-format --branch: strip refs/heads/ using skip_prefix

diff --git a/builtin/name-rev.c b/builtin/name-rev.c
index e7a3fe7ee70759c34b9de12177078a55f27bfb9a..1767af750dde7f5184b4df25067f9f616c1918b3 100644 (file)
--- a/builtin/name-rev.c
+++ b/builtin/name-rev.c
@@ -13,6 +13,7 @@ typedef struct rev_name {
        unsigned long taggerdate;
        int generation;
        int distance;
+       int from_tag;
 } rev_name;
 
 static long cutoff = LONG_MAX;
@@ -20,9 +21,47 @@ static long cutoff = LONG_MAX;
 /* How many generations are maximally preferred over _one_ merge traversal? */
 #define MERGE_TRAVERSAL_WEIGHT 65535
 
+static int is_better_name(struct rev_name *name,
+                         const char *tip_name,
+                         unsigned long taggerdate,
+                         int generation,
+                         int distance,
+                         int from_tag)
+{
+       /*
+        * When comparing names based on tags, prefer names
+        * based on the older tag, even if it is farther away.
+        */
+       if (from_tag && name->from_tag)
+               return (name->taggerdate > taggerdate ||
+                       (name->taggerdate == taggerdate &&
+                        name->distance > distance));
+
+       /*
+        * We know that at least one of them is a non-tag at this point.
+        * favor a tag over a non-tag.
+        */
+       if (name->from_tag != from_tag)
+               return from_tag;
+
+       /*
+        * We are now looking at two non-tags.  Tiebreak to favor
+        * shorter hops.
+        */
+       if (name->distance != distance)
+               return name->distance > distance;
+
+       /* ... or tiebreak to favor older date */
+       if (name->taggerdate != taggerdate)
+               return name->taggerdate > taggerdate;
+
+       /* keep the current one if we cannot decide */
+       return 0;
+}
+
 static void name_rev(struct commit *commit,
                const char *tip_name, unsigned long taggerdate,
-               int generation, int distance,
+               int generation, int distance, int from_tag,
                int deref)
 {
        struct rev_name *name = (struct rev_name *)commit->util;
@@ -46,14 +85,14 @@ static void name_rev(struct commit *commit,
                name = xmalloc(sizeof(rev_name));
                commit->util = name;
                goto copy_data;
-       } else if (name->taggerdate > taggerdate ||
-                       (name->taggerdate == taggerdate &&
-                        name->distance > distance)) {
+       } else if (is_better_name(name, tip_name, taggerdate,
+                                 generation, distance, from_tag)) {
 copy_data:
                name->tip_name = tip_name;
                name->taggerdate = taggerdate;
                name->generation = generation;
                name->distance = distance;
+               name->from_tag = from_tag;
        } else {
                free(to_free);
                return;
@@ -75,10 +114,12 @@ static void name_rev(struct commit *commit,
                                                   parent_number);
 
                        name_rev(parents->item, new_name, taggerdate, 0,
-                               distance + MERGE_TRAVERSAL_WEIGHT, 0);
+                                distance + MERGE_TRAVERSAL_WEIGHT,
+                                from_tag, 0);
                } else {
                        name_rev(parents->item, tip_name, taggerdate,
-                               generation + 1, distance + 1, 0);
+                                generation + 1, distance + 1,
+                                from_tag, 0);
                }
        }
 }
@@ -209,9 +250,13 @@ static int name_ref(const char *path, const struct object_id *oid, int flags, vo
        }
        if (o && o->type == OBJ_COMMIT) {
                struct commit *commit = (struct commit *)o;
+               int from_tag = starts_with(path, "refs/tags/");
 
+               if (taggerdate == ULONG_MAX)
+                       taggerdate = ((struct commit *)o)->date;
                path = name_ref_abbrev(path, can_abbreviate_output);
-               name_rev(commit, xstrdup(path), taggerdate, 0, 0, deref);
+               name_rev(commit, xstrdup(path), taggerdate, 0, 0,
+                        from_tag, deref);
        }
        return 0;
 }