test-lib: refactor $GIT_SKIP_TESTS matching

It's already used twice, and we will have more of the same kind of
matching in a minute.

Helped-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Thomas Rast <trast@inf.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/test-lib.sh b/t/test-lib.sh
index 229f5f7..4c583b0 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -328,6 +328,20 @@
 	test "$debug" = "" || eval "$1"
 }
 
+match_pattern_list () {
+	arg="$1"
+	shift
+	test -z "$*" && return 1
+	for pattern_
+	do
+		case "$arg" in
+		$pattern_)
+			return 0
+		esac
+	done
+	return 1
+}
+
 test_eval_ () {
 	# This is a separate function because some tests use
 	# "return" to end a test_expect_success block early.
@@ -358,14 +372,10 @@
 test_skip () {
 	test_count=$(($test_count+1))
 	to_skip=
-	for skp in $GIT_SKIP_TESTS
-	do
-		case $this_test.$test_count in
-		$skp)
-			to_skip=t
-			break
-		esac
-	done
+	if match_pattern_list $this_test.$test_count $GIT_SKIP_TESTS
+	then
+		to_skip=t
+	fi
 	if test -z "$to_skip" && test -n "$test_prereq" &&
 	   ! test_have_prereq "$test_prereq"
 	then
@@ -630,15 +640,12 @@
 
 this_test=${0##*/}
 this_test=${this_test%%-*}
-for skp in $GIT_SKIP_TESTS
-do
-	case "$this_test" in
-	$skp)
-		say_color info >&3 "skipping test $this_test altogether"
-		skip_all="skip all tests in $this_test"
-		test_done
-	esac
-done
+if match_pattern_list "$this_test" $GIT_SKIP_TESTS
+then
+	say_color info >&3 "skipping test $this_test altogether"
+	skip_all="skip all tests in $this_test"
+	test_done
+fi
 
 # Provide an implementation of the 'yes' utility
 yes () {