Upgrade to php 8.1 (#80)

* fix function signature

* more signature #[\ReturnTypeWillChange]

src/Schema.php

@@ -1906,6 +1906,7 @@ private function callValidators($value, ValidationField $field) {
      * @link http://php.net/manual/en/jsonserializable.jsonserialize.php
      * @link http://json-schema.org/
      */
+    #[\ReturnTypeWillChange]
     public function jsonSerialize() {
         $seen = [$this];
         return $this->jsonSerializeInternal($seen);
@@ -2080,6 +2081,7 @@ public function setID(string $id) {
      * @return boolean true on success or false on failure.
      * @link http://php.net/manual/en/arrayaccess.offsetexists.php
      */
+    #[\ReturnTypeWillChange]
     public function offsetExists($offset) {
         return isset($this->schema[$offset]);
     }
@@ -2091,6 +2093,7 @@ public function offsetExists($offset) {
      * @return mixed Can return all value types.
      * @link http://php.net/manual/en/arrayaccess.offsetget.php
      */
+    #[\ReturnTypeWillChange]
     public function offsetGet($offset) {
         return isset($this->schema[$offset]) ? $this->schema[$offset] : null;
     }
@@ -2102,6 +2105,7 @@ public function offsetGet($offset) {
      * @param mixed $value The value to set.
      * @link http://php.net/manual/en/arrayaccess.offsetset.php
      */
+    #[\ReturnTypeWillChange]
     public function offsetSet($offset, $value) {
         $this->schema[$offset] = $value;
     }
@@ -2112,6 +2116,7 @@ public function offsetSet($offset, $value) {
      * @param mixed $offset The offset to unset.
      * @link http://php.net/manual/en/arrayaccess.offsetunset.php
      */
+    #[\ReturnTypeWillChange]
     public function offsetUnset($offset) {
         unset($this->schema[$offset]);
     }

src/Validation.php

@@ -578,6 +578,7 @@ public function getConcatMessage($field = null, string $sep = ' ', bool $punctua
      * which is a value of any type other than a resource.
      * @link http://php.net/manual/en/jsonserializable.jsonserialize.php
      */
+    #[\ReturnTypeWillChange]
     public function jsonSerialize() {
         $errors = [];
 

src/ValidationException.php

@@ -36,6 +36,7 @@ public function __construct(Validation $validation) {
      * @return mixed data which can be serialized by <b>json_encode</b>,
      * which is a value of any type other than a resource.
      */
+    #[\ReturnTypeWillChange]
     public function jsonSerialize() {
         return $this->validation->jsonSerialize();
     }

tests/StringValidationTest.php

@@ -194,7 +194,7 @@ public function testPattern($str, $code = '', $pattern = '^[a-z]o+$') {
             if (!empty($code)) {
                 $this->fail("'$str' shouldn't validate against a pattern of $pattern.");
             } else {
-                $this->assertRegExp("/{$pattern}/", $str);
+                $this->assertMatchesRegularExpression("/{$pattern}/", $str);
             }
         } catch (ValidationException $ex) {
             $this->assertFieldHasError($ex->getValidation(), 'str', $code);