Optimize code

src/Rules/Domainname.php

@@ -69,7 +69,7 @@ private function isValidLabel(string $value): bool
      */
     private function isValidALabel(string $value): bool
     {
-        return substr($value, 0, 4) === 'xn--' && $this->idnToUtf8($value) !== false;
+        return substr($value, 0, 4) === 'xn--' && $this->idnToUtf8($value) != false;
     }
 
     /**

src/Rules/Grid.php

@@ -73,6 +73,14 @@ private function hasValidChecksum(string $value): bool
      */
     private function charValue(string $char): int
     {
-        return is_numeric($char) ? (int) $char : (int) str_replace(range('A', 'Z'), range(10, 35), strtoupper($char));
+        if (is_numeric($char)) {
+            return (int) $char;
+        }
+
+        return (int) str_replace(
+            range('A', 'Z'),
+            array_map(fn (int $val) => strval($val), range(10, 35)),
+            strtoupper($char),
+        );
     }
 }

src/Rules/Isin.php

@@ -69,7 +69,11 @@ public function normalize(string $value): string
      */
     private function replaceChars(string $value): string
     {
-        return str_replace($this->chars, array_keys($this->chars), $value);
+        return str_replace(
+            $this->chars,
+            array_map(fn (int $value) => strval($value), array_keys($this->chars)),
+            $value,
+        );
     }
 
     /**

src/Rules/Postalcode.php

@@ -14,7 +14,7 @@ class Postalcode extends AbstractRule implements DataAwareRule
      *
      * @var ?string
      */
-    private ?string $reference;
+    private ?string $reference = null;
 
     /**
      * Data set used for validation
@@ -30,6 +30,7 @@ class Postalcode extends AbstractRule implements DataAwareRule
      */
     public function __construct(protected array $countrycodes = [])
     {
+        //
     }
 
     /**
@@ -112,7 +113,7 @@ private function countryCodes(): array
     {
         if (count($this->countrycodes) == 0) {
             // return country code by reference
-            if (is_array($this->data) && array_key_exists($this->reference, $this->data)) {
+            if (!is_null($this->reference) && array_key_exists($this->reference, $this->data)) {
                 return [$this->data[$this->reference]];
             }
         }
@@ -151,7 +152,7 @@ private function pattern(string $countrycode): ?string
             'sz' => "/^[a-z]{1}[0-9]{3}$/i",
             'tw' => "/^[0-9]{3}([0-9]{2})?$/",
             'gb' => "/^(([a-z][0-9])|([a-z][0-9]{2})|([a-z][0-9][a-z])|([a-z]{2}[0-9])" .
-                    "|([a-z]{2}[0-9]{2})|([a-z]{2}[0-9][a-z])) [0-9][a-z]{2}$/i",
+                "|([a-z]{2}[0-9]{2})|([a-z]{2}[0-9][a-z])) [0-9][a-z]{2}$/i",
             'ie' => "/^[A-Za-z][A-Za-z0-9]{2} [A-Za-z0-9]{4}$/i",
             default => null,
         };