"diff --check" should affect exit status

"git diff" has a --check option that can be used to check for whitespace
problems but it only reported by printing warnings to the
console.

Now when the --check option is used we give a non-zero exit status,
making "git diff --check" nicer to use in scripts and hooks.

Signed-off-by: Wincent Colaiuta <win@wincent.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 14 insertions, 14 deletions

diff --git a/builtin-diff-tree.c b/builtin-diff-tree.c
index 2e13716..9ab90cb 100644
--- a/builtin-diff-tree.c
+++ b/builtin-diff-tree.c
@@ -117,23 +117,23 @@ int cmd_diff_tree(int argc, const char **argv, const char *prefix)
 		break;
 	}
 
-	if (!read_stdin)
-		return DIFF_OPT_TST(&opt->diffopt, EXIT_WITH_STATUS)
-			&& DIFF_OPT_TST(&opt->diffopt, HAS_CHANGES);
+	if (read_stdin) {
+		if (opt->diffopt.detect_rename)
+			opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
+					       DIFF_SETUP_USE_CACHE);
+		while (fgets(line, sizeof(line), stdin)) {
+			unsigned char sha1[20];
 
-	if (opt->diffopt.detect_rename)
-		opt->diffopt.setup |= (DIFF_SETUP_USE_SIZE_CACHE |
-				       DIFF_SETUP_USE_CACHE);
-	while (fgets(line, sizeof(line), stdin)) {
-		unsigned char sha1[20];
-
-		if (get_sha1_hex(line, sha1)) {
-			fputs(line, stdout);
-			fflush(stdout);
+			if (get_sha1_hex(line, sha1)) {
+				fputs(line, stdout);
+				fflush(stdout);
+			}
+			else
+				diff_tree_stdin(line);
 		}
-		else
-			diff_tree_stdin(line);
 	}
+	if (opt->diffopt.output_format & DIFF_FORMAT_CHECKDIFF)
+		return DIFF_OPT_TST(&opt->diffopt, CHECK_FAILED) != 0;
 	return DIFF_OPT_TST(&opt->diffopt, EXIT_WITH_STATUS)
 		&& DIFF_OPT_TST(&opt->diffopt, HAS_CHANGES);
 }