fsck: exit with non-zero status upon error from fsck_obj()

Upon finding a corrupt loose object, we forgot to note the error to
signal it with the exit status of the entire process.

[jc: adjusted t1450 and added another test]

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/fsck.c

diff --git a/builtin/fsck.c b/builtin/fsck.c
index 1affdd5..8abe644 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -389,7 +389,8 @@
 		unsigned char *sha1 = entry->sha1;
 
 		sha1_list.entry[i] = NULL;
-		fsck_sha1(sha1);
+		if (fsck_sha1(sha1))
+			errors_found |= ERROR_OBJECT;
 		free(entry);
 	}
 	sha1_list.nr = 0;

t/t1450-fsck.sh

diff --git a/t/t1450-fsck.sh b/t/t1450-fsck.sh
index 8c739c9..0de755c 100755
--- a/t/t1450-fsck.sh
+++ b/t/t1450-fsck.sh
@@ -69,7 +69,7 @@
 	git update-ref refs/heads/bogus $cmt &&
 	test_when_finished "git update-ref -d refs/heads/bogus" &&
 
-	test_might_fail git fsck 2>out &&
+	test_must_fail git fsck 2>out &&
 	cat out &&
 	grep "$sha.*corrupt" out
 '
@@ -101,7 +101,7 @@
 	test_when_finished "remove_object $new" &&
 	git update-ref refs/heads/bogus "$new" &&
 	test_when_finished "git update-ref -d refs/heads/bogus" &&
-	git fsck 2>out &&
+	test_must_fail git fsck 2>out &&
 	cat out &&
 	grep "error in commit $new" out
 '
@@ -113,7 +113,7 @@
 	test_when_finished "remove_object $new" &&
 	git update-ref refs/heads/bogus "$new" &&
 	test_when_finished "git update-ref -d refs/heads/bogus" &&
-	git fsck 2>out &&
+	test_must_fail git fsck 2>out &&
 	cat out &&
 	grep "error in commit $new.* - bad name" out
 '
@@ -125,7 +125,7 @@
 	test_when_finished "remove_object $new" &&
 	git update-ref refs/heads/bogus "$new" &&
 	test_when_finished "git update-ref -d refs/heads/bogus" &&
-	git fsck 2>out &&
+	test_must_fail git fsck 2>out &&
 	cat out &&
 	grep "error in commit $new.* - missing email" out
 '
@@ -137,7 +137,7 @@
 	test_when_finished "remove_object $new" &&
 	git update-ref refs/heads/bogus "$new" &&
 	test_when_finished "git update-ref -d refs/heads/bogus" &&
-	git fsck 2>out &&
+	test_must_fail git fsck 2>out &&
 	cat out &&
 	grep "error in commit $new" out
 '
@@ -151,11 +151,31 @@
 	test_when_finished "remove_object $new" &&
 	git update-ref refs/heads/bogus "$new" &&
 	test_when_finished "git update-ref -d refs/heads/bogus" &&
-	git fsck 2>out &&
+	test_must_fail git fsck 2>out &&
 	cat out &&
 	grep "error in commit $new.*integer overflow" out
 '
 
+test_expect_success 'malformatted tree object' '
+	test_when_finished "git update-ref -d refs/tags/wrong" &&
+	test_when_finished "remove_object \$T" &&
+	T=$(
+		GIT_INDEX_FILE=test-index &&
+		export GIT_INDEX_FILE &&
+		rm -f test-index &&
+		>x &&
+		git add x &&
+		T=$(git write-tree) &&
+		(
+			git cat-file tree $T &&
+			git cat-file tree $T
+		) |
+		git hash-object -w -t tree --stdin
+	) &&
+	test_must_fail git fsck 2>out &&
+	grep "error in tree .*contains duplicate file entries" out
+'
+
 test_expect_success 'tag pointing to nonexistent' '
 	cat >invalid-tag <<-\EOF &&
 	object ffffffffffffffffffffffffffffffffffffffff

t/t4212-log-corrupt.sh

diff --git a/t/t4212-log-corrupt.sh b/t/t4212-log-corrupt.sh
index 58b792b..67bd8ec 100755
--- a/t/t4212-log-corrupt.sh
+++ b/t/t4212-log-corrupt.sh
@@ -14,7 +14,7 @@
 '
 
 test_expect_success 'fsck notices broken commit' '
-	git fsck 2>actual &&
+	test_must_fail git fsck 2>actual &&
 	test_i18ngrep invalid.author actual
 '