assertResponseHasHeader example

        $this->getResponseTester(new Response('', 200, ['Content-Type' => 'application/vnd.myformat']))->assertResponseFormatSame('custom');
        $this->getResponseTester(new Response('', 200, ['Content-Type' => 'application/ld+json']))->assertResponseFormatSame('jsonld');
        $this->getResponseTester(new Response())->assertResponseFormatSame(null);
        $this->expectException(AssertionFailedError::class);
        $this->expectExceptionMessage("Failed asserting that the Response format is jsonld.\nHTTP/1.0 200 OK");
        $this->getResponseTester(new Response())->assertResponseFormatSame('jsonld');
    }

    public function testAssertResponseHasHeader()
    {
        $this->getResponseTester(new Response())->assertResponseHasHeader('Date');
        $this->expectException(AssertionFailedError::class);
        $this->expectExceptionMessage('Failed asserting that the Response has header "X-Date".');
        $this->getResponseTester(new Response())->assertResponseHasHeader('X-Date');
    }

    public function testAssertResponseNotHasHeader()
    {
        $this->getResponseTester(new Response())->assertResponseNotHasHeader('X-Date');
        $this->expectException(AssertionFailedError::class);
        $this->expectExceptionMessage('Failed asserting that the Response does not have header "Date".');
        $this->getResponseTester(new Response())->assertResponseNotHasHeader('Date');
    }