Subject: Re: git status: small difference between stating whole repository and small subdirectory

From: Nguyen Thai Ngoc Duy <[email-masked]>
Date: Mon, 20 Feb 2012 21:36:44 +0700

On Mon, Feb 20, 2012 at 03:09:57PM +0100, Thomas Rast wrote:
> > Interestingly, on my git.git repo, I had an empty cache. Running "git
> > read-tree HEAD" filled it (according to test-dump-cache-tree). It seems
> > that running "git checkout" empties the cache.  So perhaps git could do
> > better about keeping the cache valid over time.
> 
> test_expect_failure 'checkout gives cache-tree' '
> 	git checkout HEAD^ &&
> 	test_shallow_cache_tree
> '
> 
> ;-)

Quick and dirty that passes that test. I think we could do better if
we analyse two way merge rules carefully and avoid this diff, but
that's too much for me right now.

-- 8< --
diff --git a/builtin/checkout.c b/builtin/checkout.c
index 5bf96ba..c06287a 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c
@@ -319,6 +319,10 @@ static void show_local_changes(struct object *head, struct diff_options *opts)
 		die(_("diff_setup_done failed"));
 	add_pending_object(&rev, head, NULL);
 	run_diff_index(&rev, 0);
+	if (!DIFF_OPT_TST(&rev.diffopt, HAS_CHANGES)) {
+		struct tree *tree = parse_tree_indirect(head->sha1);
+		prime_cache_tree(&active_cache_tree, tree);
+	}
 }
 
 static void describe_detached_head(const char *msg, struct commit *commit)
@@ -493,13 +497,13 @@ static int merge_working_tree(struct checkout_opts *opts,
 		}
 	}
 
+	if (!opts->force && !opts->quiet)
+		show_local_changes(&new->commit->object, &opts->diff_options);
+
 	if (write_cache(newfd, active_cache, active_nr) ||
 	    commit_locked_index(lock_file))
 		die(_("unable to write new index file"));
 
-	if (!opts->force && !opts->quiet)
-		show_local_changes(&new->commit->object, &opts->diff_options);
-
 	return 0;
 }
 
-- 8< --
-- 
Duy