test(ArcadiaEmployeeId): add unit tests for ArcadiaEmployeeId value object

tests/Unit/Domain/Models/ValueObjects/Entities/ArcadiaEmployeeIdTest.php

@@ -33,15 +33,6 @@ describe('ArcadiaEmployeeId Value Object', function (): void {
             ->and((string) $employeeId)->toBe('01155902');
     });
 
-    it('throws a DomainException when given an invalid matricule pattern', function (): void {
-        // GIVEN
-        $invalidMatricule = '12345';
-
-        // WHEN & THEN
-        expect(fn () => new ArcadiaEmployeeId($invalidMatricule))
-            ->toThrow(\DomainException::class);
-    });
-
     it('supports equality check with another ArcadiaEmployeeId instance', function (): void {
         // GIVEN
         $firstId     = new ArcadiaEmployeeId('01155902');
@@ -54,4 +45,24 @@ describe('ArcadiaEmployeeId Value Object', function (): void {
             ->and($firstId->equals($differentId))
             ->toBeFalse();
     });
+
+    it('can be converted to a string representation', function (): void {
+        // GIVEN
+        $employeeId = new ArcadiaEmployeeId('01155902');
+
+        // WHEN
+        $stringRepresentation = (string) $employeeId;
+
+        // THEN
+        expect($stringRepresentation)->toBe('01155902');
+    });
+
+    it('throws a DomainException when given an invalid matricule pattern', function (): void {
+        // GIVEN
+        $invalidMatricule = '12345';
+
+        // WHEN & THEN
+        expect(fn () => new ArcadiaEmployeeId($invalidMatricule))
+            ->toThrow(\DomainException::class);
+    });
 });