t/: Use "test_must_fail git" instead of "! git"

diff --git a/t/t4150-am.sh b/t/t4150-am.sh
index bc982607d09bbdeb0d486eb282f5756a48ae5bcb..476f20b50a402f6843b4588d93d3acfdacf3603b 100755 (executable)
--- a/t/t4150-am.sh
+++ b/t/t4150-am.sh
@@ -182,7 +182,7 @@ test_expect_success 'am -3 falls back to 3-way merge' '
 
 test_expect_success 'am pauses on conflict' '
        git checkout lorem2^^ &&
-       ! git am lorem-move.patch &&
+       test_must_fail git am lorem-move.patch &&
        test -d .dotest
 '
 
@@ -195,7 +195,7 @@ test_expect_success 'am --skip works' '
 
 test_expect_success 'am --resolved works' '
        git checkout lorem2^^ &&
-       ! git am lorem-move.patch &&
+       test_must_fail git am lorem-move.patch &&
        test -d .dotest &&
        echo resolved >>file &&
        git add file &&
@@ -212,13 +212,13 @@ test_expect_success 'am takes patches from a Pine mailbox' '
 '
 
 test_expect_success 'am fails on mail without patch' '
-       ! git am <failmail &&
+       test_must_fail git am <failmail &&
        rm -r .dotest/
 '
 
 test_expect_success 'am fails on empty patch' '
        echo "---" >>failmail &&
-       ! git am <failmail &&
+       test_must_fail git am <failmail &&
        git am --skip &&
        ! test -d .dotest
 '