t4001: don't run 'git status' upstream of a pipe

The primary purpose of three tests in 't4001-diff-rename.sh' is to
check rename detection in 'git status', but all three do so by running
'git status' upstream of a pipe, hiding its exit code.  Consequently,
the test could continue even if 'git status' exited with error.

Use an intermediate file between 'git status' and 'test_i18ngrep' to
catch a potential failure of the former.

Signed-off-by: SZEDER Gábor <[email protected]>
Reviewed-by: Jeff King <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: szeder

t/t4001-diff-rename.sh

@@ -134,11 +134,15 @@ test_expect_success 'favour same basenames over different ones' '
 	git rm path1 &&
 	mkdir subdir &&
 	git mv another-path subdir/path1 &&
-	git status | test_i18ngrep "renamed: .*path1 -> subdir/path1"'
+	git status >out &&
+	test_i18ngrep "renamed: .*path1 -> subdir/path1" out
+'
 
 test_expect_success 'favour same basenames even with minor differences' '
 	git show HEAD:path1 | sed "s/15/16/" > subdir/path1 &&
-	git status | test_i18ngrep "renamed: .*path1 -> subdir/path1"'
+	git status >out &&
+	test_i18ngrep "renamed: .*path1 -> subdir/path1" out
+'
 
 test_expect_success 'two files with same basename and same content' '
 	git reset --hard &&
@@ -148,7 +152,8 @@ test_expect_success 'two files with same basename and same content' '
 	git add dir &&
 	git commit -m 2 &&
 	git mv dir other-dir &&
-	git status | test_i18ngrep "renamed: .*dir/A/file -> other-dir/A/file"
+	git status >out &&
+	test_i18ngrep "renamed: .*dir/A/file -> other-dir/A/file" out
 '
 
 test_expect_success 'setup for many rename source candidates' '