class ChainResponsePolicyTest

class ChainResponsePolicyTest extends UnitTestCase {
    
    /**
     * The chain response policy under test.
     *
     * @var \Drupal\Core\PageCache\ChainResponsePolicy
     */
    protected $policy;
    
    /**
     * A request object.
     *
     * @var \Symfony\Component\HttpFoundation\Request
     */
    protected $request;
    
    /**
     * A response object.
     *
     * @var \Symfony\Component\HttpFoundation\Response
     */
    protected $response;
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() : void {
        $this->policy = new ChainResponsePolicy();
        $this->response = new Response();
        $this->request = new Request();
    }
    
    /**
     * Asserts that check() returns NULL if the chain is empty.
     *
     * @covers ::check
     */
    public function testEmptyChain() {
        $result = $this->policy
            ->check($this->response, $this->request);
        $this->assertSame(NULL, $result);
    }
    
    /**
     * Asserts that check() returns NULL if a rule returns NULL.
     *
     * @covers ::check
     */
    public function testNullRuleChain() {
        $rule = $this->createMock('Drupal\\Core\\PageCache\\ResponsePolicyInterface');
        $rule->expects($this->once())
            ->method('check')
            ->with($this->response, $this->request)
            ->willReturn(NULL);
        $this->policy
            ->addPolicy($rule);
        $result = $this->policy
            ->check($this->response, $this->request);
        $this->assertSame(NULL, $result);
    }
    
    /**
     * Asserts that check() throws an exception if a rule returns an invalid value.
     *
     * @dataProvider providerChainExceptionOnInvalidReturnValue
     * @covers ::check
     */
    public function testChainExceptionOnInvalidReturnValue($return_value) {
        $rule = $this->createMock('Drupal\\Core\\PageCache\\ResponsePolicyInterface');
        $rule->expects($this->once())
            ->method('check')
            ->with($this->response, $this->request)
            ->willReturn($return_value);
        $this->policy
            ->addPolicy($rule);
        $this->expectException(\UnexpectedValueException::class);
        $this->policy
            ->check($this->response, $this->request);
    }
    
    /**
     * Provides test data for testChainExceptionOnInvalidReturnValue.
     *
     * @return array
     *   Test input and expected result.
     */
    public function providerChainExceptionOnInvalidReturnValue() {
        return [
            [
                FALSE,
            ],
            [
                0,
            ],
            [
                1,
            ],
            [
                TRUE,
            ],
            [
                [
                    1,
                    2,
                    3,
                ],
            ],
            [
                new \stdClass(),
            ],
        ];
    }
    
    /**
     * Asserts that check() returns immediately when a rule returned DENY.
     */
    public function testStopChainOnFirstDeny() {
        $rule1 = $this->createMock('Drupal\\Core\\PageCache\\ResponsePolicyInterface');
        $rule1->expects($this->once())
            ->method('check')
            ->with($this->response, $this->request);
        $this->policy
            ->addPolicy($rule1);
        $deny_rule = $this->createMock('Drupal\\Core\\PageCache\\ResponsePolicyInterface');
        $deny_rule->expects($this->once())
            ->method('check')
            ->with($this->response, $this->request)
            ->willReturn(ResponsePolicyInterface::DENY);
        $this->policy
            ->addPolicy($deny_rule);
        $ignored_rule = $this->createMock('Drupal\\Core\\PageCache\\ResponsePolicyInterface');
        $ignored_rule->expects($this->never())
            ->method('check');
        $this->policy
            ->addPolicy($ignored_rule);
        $actual_result = $this->policy
            ->check($this->response, $this->request);
        $this->assertSame(ResponsePolicyInterface::DENY, $actual_result);
    }

}