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phpunit-testingmockery

How to throw an exception on the Nth call of a mock method with Mockery


I need to test how some code I wrote will behave when it calls a method on another class multiple times, where one of the calls will cause an exception to be thrown.

I am using Mockery to mock the class that may throw an exception.

So in my case, the method will be called three times and I need it throw an exception on the second time.

This is example of my intention but it doesn't work.

$mock = \Mockery::mock();
$mock->shouldReceive('fetch')
    ->andReturnUsing(
        function () {return true;},
        function () use ($e) {throw new \Exception();},
        function () {return false;}
    );

I was given the impression the above might work from the response in Asserting that mock throws exception · Issue #308 · mockery/mockery.

However, in practice, throwing an exception this way causes Mockery to catch the exception and throw its own BadMethodCall exception.


Solution

  • I found the answer amongst the Mockery Github Issues, Mock multiple method call with return and throw.

    $mock = \Mockery::mock();
    $mock->shouldReceive('fetch')
        ->andReturnUsing(
            function () use () {
                static $counter = 0;
    
                switch ($counter++) {
                    case 0:
                        return true;
                        break;
                    case 1:
                        throw new \Exception();
                        break;
                    default:
                        return false;
                        break;
                }
            }
        );
    

    For those looking for a solution using PHPUnit...

    $mockHydrator = $this->createMock(MyObject::class);
    $mockHydrator->method('fetch')
        ->will(
            $this->onConsecutiveCalls(
                true,
                $this->throwException($e),
                false
            )
        );
    

    This is one case where I feel PHPUnit mocks provides a better interface than Mockery.