rename conversion function

Author: edudobay

src/JWK.php

@@ -174,7 +174,7 @@ public static function parseKey(array $jwk, string $defaultAlg = null): ?Key
                     throw new UnexpectedValueException('x not set');
                 }
 
-                $publicKey = JWT::urlsafeToStandardB64($jwk['x']);
+                $publicKey = JWT::convertBase64urlToBase64($jwk['x']);
                 $alg = self::OKP_CURVES[$jwk['crv']];
                 return new Key($publicKey, $alg);
             default:

src/JWT.php

@@ -400,18 +400,20 @@ public static function jsonEncode(array $input): string
      */
     public static function urlsafeB64Decode(string $input): string
     {
-        return \base64_decode(self::urlsafeToStandardB64($input));
+        return \base64_decode(self::convertBase64urlToBase64($input));
     }
 
     /**
-     * Convert a string from URL-safe Base64 to standard Base64.
+     * Convert a string in the base64url (URL-safe Base64) encoding to standard base64.
      *
      * @param string $input A Base64 encoded string with URL-safe characters (-_ and no padding)
      *
      * @return string A Base64 encoded string with standard characters (+/) and padding (=), when
      * needed.
+     *
+     * @see https://www.rfc-editor.org/rfc/rfc4648
      */
-    public static function urlsafeToStandardB64(string $input): string
+    public static function convertBase64urlToBase64(string $input): string
     {
         $remainder = \strlen($input) % 4;
         if ($remainder) {