fix: Enhance BIC generation and add tests

CHANGELOG.md

@@ -5,6 +5,7 @@
 - Removed domain `gmail.com.au` from `Provider\en_AU\Internet` (#886)
 - Refreshed ISO currencies (#919)
 - Improved italian phone number formats
+- Fixed BIC generation for `Provider\Payment`
 
 ## [2024-11-09, v1.24.0](https://github.com/FakerPHP/Faker/compare/v1.23.1..v1.24.0)
 

src/Faker/Provider/Payment.php

@@ -302,11 +302,12 @@ public static function iban($countryCode = null, $prefix = '', $length = null)
      * @example 'RZTIAT22263'
      *
      * @see    http://en.wikipedia.org/wiki/ISO_9362
+     * @see    http://www.iso20022.org
      *
      * @return string Swift/Bic number
      */
-    public static function swiftBicNumber()
+    public static function swiftBicNumber(): string
     {
-        return self::regexify('^([A-Z]){4}([A-Z]){2}([0-9A-Z]){2}([0-9A-Z]{3})?$');
+        return self::regexify('^([A-Z]{6,6}[A-Z2-9][A-NP-Z0-9][A-Z0-9]{3,3}){0,1}$');
     }
 }

test/Faker/Provider/PaymentTest.php

@@ -187,6 +187,14 @@ public function testIban($countryCode, $regex): void
         self::assertTrue(Iban::isValid($iban), "Checksum for $iban is invalid");
     }
 
+    public function testSwitchBicNumber(): void
+    {
+        $bic = $this->faker->swiftBicNumber();
+
+        // Test format
+        self::assertMatchesRegularExpression('~^[A-Z]{6,6}[A-Z2-9][A-NP-Z0-9]([A-Z0-9]{3,3}){0,1}$~', $bic, "Bic for $bic is invalid");
+    }
+
     protected function getProviders(): iterable
     {
         yield new BaseProvider($this->faker);