[PATCH] Ensure that commit/status don't stat all files when core.ignoreStat = true

[Marius Storm-Olsen <marius@trolltech.com>]

The core.ignoreStat option is used to assume that files in the
index are unchanged, thus avoiding expensive lstat()s on slow
systems. However, due to refresh_cache_ent still stating but
ignoring the info, and the listing of untracked files in
commit/status, we would still lstat() all the files.

This change shortcuts the refresh_cache_ent(), and makes
commit/status not list untracked files, unless the -u option
is specified.

Signed-off-by: Marius Storm-Olsen <marius@trolltech.com>
---
 read-cache.c |   10 ++++++++++
 wt-status.c  |   11 ++++++++++-
 2 files changed, 20 insertions(+), 1 deletions(-)

diff --git a/read-cache.c b/read-cache.c
index 8b467f8..104e387 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -882,6 +882,16 @@ static struct cache_entry *refresh_cache_ent(struct index_state *istate,
 	if (ce_uptodate(ce))
 		return ce;
 
+	/*
+	 * assume_unchanged is used to avoid lstats to check if the
+	 * file has been modified. When true, the user need to
+	 * manually update the index.
+	 */
+	if (assume_unchanged) {
+		ce_mark_uptodate(ce);
+		return ce;
+	}
+
 	if (lstat(ce->name, &st) < 0) {
 		if (err)
 			*err = errno;
diff --git a/wt-status.c b/wt-status.c
index a44c543..72db466 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -342,7 +342,14 @@ void wt_status_print(struct wt_status *s)
 	wt_status_print_changed(s);
 	if (wt_status_submodule_summary)
 		wt_status_print_submodule_summary(s);
-	wt_status_print_untracked(s);
+
+	if (assume_unchanged && !s->untracked) {
+		if (s->commitable)
+			fprintf(s->fp, "# Untracked files not listed (use -u option to show untracked files)\n");
+		/* !s->commitable message displayed below */
+	}
+	else
+		wt_status_print_untracked(s);
 
 	if (s->verbose && !s->is_initial)
 		wt_status_print_verbose(s);
@@ -357,6 +364,8 @@ void wt_status_print(struct wt_status *s)
 			printf("nothing added to commit but untracked files present (use \"git add\" to track)\n");
 		else if (s->is_initial)
 			printf("nothing to commit (create/copy files and use \"git add\" to track)\n");
+		else if (assume_unchanged && !s->untracked)
+			printf("nothing to commit (use -u to show untracked files)\n");
 		else
 			printf("nothing to commit (working directory clean)\n");
 	}
-- 
1.5.5.1.501.gefb4