Fix unserialization behaviour

src/Immutable.php

@@ -55,4 +55,11 @@ final public function __get($name)
 
         return $this->_defaultValues[$name];
     }
+
+    final public function __wakeup()
+    {
+        foreach ($this->_userDefinedProperties as $property => $defined) {
+            unset($this->{$property});
+        }
+    }
 }

test/SerializationTest.php

@@ -0,0 +1,25 @@
+<?php
+
+
+namespace ConvenientImmutability\Test;
+
+use ConvenientImmutability\Test\Resources\Foo;
+
+class SerializationTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @test
+     */
+    public function it_should_be_same_after_serialization()
+    {
+        $foo = new Foo();
+        $foo->bar = 1;
+        $foo->baz = 2;
+
+        $serializedValue = serialize($foo);
+        $deSerializedValue = unserialize($serializedValue);
+
+        $this->assertSame($deSerializedValue->bar, $foo->bar);
+        $this->assertSame($deSerializedValue->baz, $foo->baz);
+    }
+}