t6030: use test_path_is_missing()

The test_must_fail() function should only be used for git commands since
we should assume that external commands work sanely. Replace
`test_must_fail test -e` with `test_path_is_missing`.

Signed-off-by: Denton Liu <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: Denton-L

t/t6030-bisect-porcelain.sh

@@ -148,7 +148,7 @@ test_expect_success 'bisect start: no ".git/BISECT_START" created if junk rev' '
 	test_must_fail git bisect start $HASH4 foo -- &&
 	git branch > branch.output &&
 	grep "* other" branch.output > /dev/null &&
-	test_must_fail test -e .git/BISECT_START
+	test_path_is_missing .git/BISECT_START
 '
 
 test_expect_success 'bisect start: existing ".git/BISECT_START" not modified if junk rev' '
@@ -166,7 +166,7 @@ test_expect_success 'bisect start: no ".git/BISECT_START" if mistaken rev' '
 	test_must_fail git bisect start $HASH1 $HASH4 -- &&
 	git branch > branch.output &&
 	grep "* other" branch.output > /dev/null &&
-	test_must_fail test -e .git/BISECT_START
+	test_path_is_missing .git/BISECT_START
 '
 
 test_expect_success 'bisect start: no ".git/BISECT_START" if checkout error' '
@@ -175,7 +175,7 @@ test_expect_success 'bisect start: no ".git/BISECT_START" if checkout error' '
 	git branch &&
 	git branch > branch.output &&
 	grep "* other" branch.output > /dev/null &&
-	test_must_fail test -e .git/BISECT_START &&
+	test_path_is_missing .git/BISECT_START &&
 	test -z "$(git for-each-ref "refs/bisect/*")" &&
 	git checkout HEAD hello
 '
@@ -485,7 +485,7 @@ test_expect_success 'optimized merge base checks' '
 	git bisect bad &&
 	git bisect good "$A_HASH" > my_bisect_log4.txt &&
 	test_i18ngrep "merge base must be tested" my_bisect_log4.txt &&
-	test_must_fail test -f ".git/BISECT_ANCESTORS_OK"
+	test_path_is_missing ".git/BISECT_ANCESTORS_OK"
 '
 
 # This creates another side branch called "parallel" with some files