t7419: change test_must_fail to ! for grep

According to t/README, test_must_fail() should only be used to test for
failure in Git commands. Replace the invocations of
`test_must_fail grep` with `! grep`.

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

diff --git a/t/t7419-submodule-set-branch.sh b/t/t7419-submodule-set-branch.sh
index c4b370ea8533984e31a9ae501994ce9926627f98..fd25f786a3655e7486222b568e91779b9b5d99bb 100755 (executable)
--- a/t/t7419-submodule-set-branch.sh
+++ b/t/t7419-submodule-set-branch.sh
@@ -34,7 +34,7 @@ test_expect_success 'submodule config cache setup' '
 
 test_expect_success 'ensure submodule branch is unset' '
        (cd super &&
-               test_must_fail grep branch .gitmodules
+               ! grep branch .gitmodules
        )
 '
 
@@ -54,7 +54,7 @@ test_expect_success 'test submodule set-branch --branch' '
 test_expect_success 'test submodule set-branch --default' '
        (cd super &&
                git submodule set-branch --default submodule &&
-               test_must_fail grep branch .gitmodules &&
+               ! grep branch .gitmodules &&
                git submodule update --remote &&
                cat <<-\EOF >expect &&
                a
@@ -80,7 +80,7 @@ test_expect_success 'test submodule set-branch -b' '
 test_expect_success 'test submodule set-branch -d' '
        (cd super &&
                git submodule set-branch -d submodule &&
-               test_must_fail grep branch .gitmodules &&
+               ! grep branch .gitmodules &&
                git submodule update --remote &&
                cat <<-\EOF >expect &&
                a