Re: [PATCH v2] Introduce <branch>@{upstream} as shortcut to the tracked branch

Hi,

On Thu, 10 Sep 2009, Jeff King wrote:

I wrote:

quoted

+	ret = tracked_suffix(*string, *len);
+	if (ret) {
+		char *ref = xstrndup(*string, *len - ret);
+		struct branch *tracking = branch_get(*ref ? ref : NULL);
+
+		free(ref);
+		if (!tracking)
+			die ("No tracking branch found for '%s'", ref);
+		if (tracking->merge && tracking->merge[0]->dst) {
+			*string = xstrdup(tracking->merge[0]->dst);
+			*len = strlen(*string);
+			return (char *)*string;
+		}
+	}
+

I don't think it is a good idea to die for !tracking, but not for
!tracking->merge. That leads to inconsistent user-visible results:

  $ git checkout HEAD^0
  $ git rev-parse HEAD@{u}
  fatal: No tracking branch found for 'HEAD'
  $ git rev-parse bogus@{u}
  bogus@{u}
  fatal: ambiguous argument 'bogus@{u}': unknown revision or path not in the working tree.
  Use '--' to separate paths from revisions

Shouldn't both cases say the same thing?

Also, your die message has two problems:

 1. It looks at ref immediately after it is free'd, spewing junk.

 2. Ref can be the empty string, which gives you the ugly:

       fatal: No tracking branch found for ''

    Should we munge that into HEAD (or "the current branch") for the
    user?

All true, but I cannot take care of it today.

Ciao,
Dscho