t5801: teach compare_refs() to accept !

Before, testing if two refs weren't equal with compare_refs() was done
with `test_must_fail compare_refs`. This was wrong for two reasons.
First, test_must_fail should only be used on git commands. Second,
negating the error code is a little heavy-handed since in the case where
one of the git invocations within compare_refs() fails, we will report
success, even though it failed at an unexpected point.

Teach compare_refs() to accept `!` as the first argument which would
_only_ negate the test_cmp()'s return code.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/t/t5801-remote-helpers.sh b/t/t5801-remote-helpers.sh
index 121e5c6edb0a21eb8a6d72d01c7edd5f45d11b2f..0f04b6cddb723316b0edf1135086405a09e4205b 100755 (executable)
--- a/t/t5801-remote-helpers.sh
+++ b/t/t5801-remote-helpers.sh
@@ -11,9 +11,15 @@ test_description='Test remote-helper import and export commands'
 PATH="$TEST_DIRECTORY/t5801:$PATH"
 
 compare_refs() {
+       fail= &&
+       if test "x$1" = 'x!'
+       then
+               fail='!' &&
+               shift
+       fi &&
        git --git-dir="$1/.git" rev-parse --verify $2 >expect &&
        git --git-dir="$3/.git" rev-parse --verify $4 >actual &&
-       test_cmp expect actual
+       eval $fail test_cmp expect actual
 }
 
 test_expect_success 'setup repository' '
@@ -189,7 +195,7 @@ test_expect_success GPG 'push signed tag' '
        git push origin signed-tag
        ) &&
        compare_refs local signed-tag^{} server signed-tag^{} &&
-       test_must_fail compare_refs local signed-tag server signed-tag
+       compare_refs ! local signed-tag server signed-tag
 '
 
 test_expect_success GPG 'push signed tag with signed-tags capability' '