Add test for corner case

Author: youkidearitai

ext/intl/tests/grapheme_levenshtein.phpt

@@ -60,8 +60,28 @@ var_dump(grapheme_levenshtein($nabe, $nabe_E0100));
 
 // combining character
 var_dump(grapheme_levenshtein("\u{0065}\u{0301}", "\u{00e9}"));
+
+// Corner case
+echo '--- Corner case ---' . PHP_EOL;
+try {
+	grapheme_levenshtein($nabe, $nabe_E0100, 0, 1, 1);
+} catch (ValueError $e) {
+	var_dump($e->getMessage());
+}
+
+try {
+	grapheme_levenshtein($nabe, $nabe_E0100, 1, 0, 1);
+} catch (ValueError $e) {
+	var_dump($e->getMessage());
+}
+
+try {
+	grapheme_levenshtein($nabe, $nabe_E0100, 1, 1, 0);
+} catch (ValueError $e) {
+	var_dump($e->getMessage());
+}
 ?>
---EXPECT--
+--EXPECTF--
 --- Equal ---
 int(0)
 --- First string empty ---
@@ -102,3 +122,7 @@ int(2)
 int(1)
 int(0)
 int(0)
+--- Corner case ---
+string(%d) "grapheme_levenshtein(): Argument #3 ($insertion_cost) must be greater than 0 and less than or equal to %d"
+string(%d) "grapheme_levenshtein(): Argument #4 ($replacement_cost) must be greater than 0 and less than or equal to %d"
+string(%d) "grapheme_levenshtein(): Argument #5 ($deletion_cost) must be greater than 0 and less than or equal to %d"