Merge branch 'bw/submodule-branch-dot-doc'
[gitweb.git] / builtin / blame.c
index a7bd7a6fd80f7d68f58d094bdc5cd6c288fb0e29..4ddfadb71f7ef93958e2f236e166212e8b6bda2b 100644 (file)
@@ -2111,7 +2111,7 @@ static void find_alignment(struct scoreboard *sb, int *option)
        unsigned largest_score = 0;
        struct blame_entry *e;
        int compute_auto_abbrev = (abbrev < 0);
-       int auto_abbrev = default_abbrev;
+       int auto_abbrev = DEFAULT_ABBREV;
 
        for (e = sb->ent; e; e = e->next) {
                struct origin *suspect = e->suspect;
@@ -2456,6 +2456,41 @@ static char *prepare_final(struct scoreboard *sb)
        return xstrdup_or_null(name);
 }
 
+static const char *dwim_reverse_initial(struct scoreboard *sb)
+{
+       /*
+        * DWIM "git blame --reverse ONE -- PATH" as
+        * "git blame --reverse ONE..HEAD -- PATH" but only do so
+        * when it makes sense.
+        */
+       struct object *obj;
+       struct commit *head_commit;
+       unsigned char head_sha1[20];
+
+       if (sb->revs->pending.nr != 1)
+               return NULL;
+
+       /* Is that sole rev a committish? */
+       obj = sb->revs->pending.objects[0].item;
+       obj = deref_tag(obj, NULL, 0);
+       if (obj->type != OBJ_COMMIT)
+               return NULL;
+
+       /* Do we have HEAD? */
+       if (!resolve_ref_unsafe("HEAD", RESOLVE_REF_READING, head_sha1, NULL))
+               return NULL;
+       head_commit = lookup_commit_reference_gently(head_sha1, 1);
+       if (!head_commit)
+               return NULL;
+
+       /* Turn "ONE" into "ONE..HEAD" then */
+       obj->flags |= UNINTERESTING;
+       add_pending_object(sb->revs, &head_commit->object, "HEAD");
+
+       sb->final = (struct commit *)obj;
+       return sb->revs->pending.objects[0].name;
+}
+
 static char *prepare_initial(struct scoreboard *sb)
 {
        int i;
@@ -2474,14 +2509,17 @@ static char *prepare_initial(struct scoreboard *sb)
                if (obj->type != OBJ_COMMIT)
                        die("Non commit %s?", revs->pending.objects[i].name);
                if (sb->final)
-                       die("More than one commit to dig down to %s and %s?",
+                       die("More than one commit to dig up from, %s and %s?",
                            revs->pending.objects[i].name,
                            final_commit_name);
                sb->final = (struct commit *) obj;
                final_commit_name = revs->pending.objects[i].name;
        }
+
+       if (!final_commit_name)
+               final_commit_name = dwim_reverse_initial(sb);
        if (!final_commit_name)
-               die("No commit to dig down to?");
+               die("No commit to dig up from?");
        return xstrdup(final_commit_name);
 }