Validators: added support for ?nullable types

Author: dg

src/Utils/Validators.php

@@ -119,6 +119,11 @@ public static function is($value, string $expected): bool
 					return true;
 				}
 				continue;
+			} elseif (substr($item, 0, 1) === '?') {
+				$item = substr($item, 1);
+				if ($value === null) {
+					return true;
+				}
 			}
 
 			[$type] = $item = explode(':', $item, 2);

tests/Utils/Validators.is().phpt

@@ -399,3 +399,11 @@ test(function () {
 	Assert::true(Validators::is([['ABCD', 'EFGH'], ['IJKL']], 'string:4[][]'));
 	Assert::false(Validators::is([['ABCD', 'EFGH'], ['IJKLM']], 'string:4[][]'));
 });
+
+
+test(function () {
+	Assert::true(Validators::is(null, '?string'));
+	Assert::true(Validators::is('1', '?string'));
+	Assert::false(Validators::is(true, '?int'));
+	Assert::false(Validators::is(0, '?string'));
+});