Symfony\Component\DependencyInjection\ContainerInterface::has PHP Method

    function has($id);

 /**
  * @covers ::knowsDependency
  * @covers ::__construct
  */
 public function testKnowsDependency()
 {
     $this->container->has('known_dependency')->willReturn(true);
     $this->container->has('unknown_dependency')->willReturn(false);
     $this->assertTrue($this->sut->knowsDependency('known_dependency'));
     $this->assertFalse($this->sut->knowsDependency('unknown_dependency'));
 }