ValueObjects\Structure\Dictionary::containsKey PHP Method

    public function containsKey(ValueObjectInterface $object)
    {
        $keys = $this->keys();
        return $keys->contains($object);
    }

 public function testContainsKey()
 {
     $one = new Integer(1);
     $ten = new Integer(10);
     $this->assertTrue($this->dictionary->containsKey($one));
     $this->assertFalse($this->dictionary->containsKey($ten));
 }