Fix cloning of datetimes (#43)

* Fix cloning of datetimes

* update tests

* php54 compat

Author: theofidry

src/DeepCopy/DeepCopy.php

@@ -141,6 +141,9 @@ private function copyObject($object)
         $newObject = clone $object;
         $this->hashMap[$objectHash] = $newObject;
 
+        if ($newObject instanceof \DateTimeInterface) {
+            return $newObject;
+        }
         foreach (ReflectionHelper::getProperties($reflectedObject) as $property) {
             $this->copyObjectProperty($newObject, $property);
         }

tests/DeepCopyTest/DeepCopyTest.php

@@ -42,6 +42,23 @@ public function testPropertyObjectCopy()
         $this->assertDeepCopyOf($o, $deepCopy->copy($o));
     }
 
+    public function testPropertyObjectCopyWithDateTimes()
+    {
+        $o = new A();
+        $o->date1 = new \DateTime();
+        if (class_exists('DateTimeImmutable')) {
+            $o->date2 = new \DateTimeImmutable();
+        }
+
+        $deepCopy = new DeepCopy();
+        $c = $deepCopy->copy($o);
+
+        $this->assertDeepCopyOf($o, $c);
+
+        $c->date1->setDate(2015, 01, 04);
+        $this->assertNotEquals($c->date1, $o->date1);
+    }
+
     public function testPrivatePropertyOfParentObjectCopy()
     {
         $o = new E();