带有回调参数的模拟方法答案

【问题标题】：Mocking method with callback param带有回调参数的模拟方法
【发布时间】：2014-02-09 09:18:04
【问题描述】：

我正在尝试模拟这种方法：

$transformer = $this->transformerFactory->createProductTransformer($product, function (ProductInterface $product) use ($discount) {
    $product->setDiscount($discount);
});

它接受回调参数作为第二个参数，我不知道如何模拟它。

我正在使用 Mockery，所以它看起来像这样：

$this->transformerFactoryMock
    ->shouldReceive('createProductTransformer')
    ->with(???) // here!

如果我将相同的回调传递给 with() 方法，则实例不匹配。如果 Mockery 不支持，我不介意使用 PHPUnit 模拟。

【问题讨论】：

标签： php unit-testing mocking phpunit mockery

【解决方案1】：

如果您需要准确检查是否调用了回调，那么这是不可能的，因为每个 \Closure 实例都是唯一的，并且在您测试的方法中您创建了新的实例。

但你可以做下一步：

1) 验证类型的动态参数

// Assume in test case you have these mock/stub
$discount;
$product;

$transformerFactoryMock = \Mockery::mock('TransformerFactory')
    ->shouldReceive('createProductTransformer')
    ->with($product, \Mockery::type(\Closure::class))

2) 检查任何隐藏的参数（在测试方法中调用模拟方法之前创建）

$transformerFactoryMock = \Mockery::mock('TransformerFactory')
    ->shouldReceive('createProductTransformer')
    ->with(function(...$args) use ($product) {
        // check any args
    })

3) 最后，使用传递给模拟方法的回调来伪造结果

// then mock will be
$transformerFactoryMock = \Mockery::mock('TransformerFactory')
    ->shouldReceive('createProductTransformer')
    ->andReturnUsing(function($closure) {
        // execute closure
        $closure();

        // any logic to fake return
        return;
    })

查看mockery complex argument matching和declaring return value的文档

【讨论】：

【解决方案2】：

如果“相同的回调”意味着相同的代码，那么它不是 PHP 的相同回调，因此 Mockery 不会接受它。

var_dump(function () {} === function () {}); // false
$func = function () {};
var_dump($func === $func); // true

要检查回调类型，您可以使用 mockery::type 方法（带有参数'closure'），更精确的检查是 mockery::on。 https://github.com/padraic/mockery#argument-validation

【讨论】：

【解决方案3】：

很难从您粘贴的 sn-p 中准确判断您要在测试文件中做什么，但您可以模拟闭包及其参数。这是一个快速/肮脏/未经测试的示例，可以最好地猜测您要完成的工作：

class Transformer {

    protected transformerFactory;

    public function __construct($factory) {
        $this->transformerFactory = $factor;
    }

    public function doSomething(Discount $discount, ProductInterface $product) {

        return $this->transformerFactory->createProductTransformer($product, function($product) use ($discount) {
            $product->setDiscount($discount);
        });
    }

}


class TransformerTest {

    protected function makeTransformerWithFakeFactory()
    {
        $fakeFactory = \Mockery::mock('TransformerFactory');

        $transformer = new Transformer($fakeFactory);

        return array($tranformer, $fakeFactory);
    }

    protected function fakeDiscount()
    {
        return \Mockery::mock('Discount');
    }

    protected function fakeProduct()
    {
        return \Mocker::mock('ProductInterface');
    }

            // first let's test to make sure that the factory's correct method is called with correct parameters
    function test_doSomething_WhenPassedProduct_CallsCreateProductTransformerOnFactoryWithProductAndClosure()
    {
        list($transformer, $mockFactory) = $this->makeTransformerWithFakeFactory();
        $fakeDiscount = $this->fakeDiscount();
        $fakeProduct = $this->fakeProduct();

        $mockFactory->shouldReceive('createProductTransformer')->once()->with($fakeProduct, \Mockery::type('Closure'));

        $transfomer->doSomething($fakeDiscount, $fakeProduct);
    }

            // now, let's test to make sure that the $discount within the closure is called with the right method and params
        function test_doSomething_createProductTransformerCalledWithProductAndClosure_CallsSetDiscountOnProductWithDiscount()
    {
        list($transformer, $stubFactory) = $this->makeTransfomerWithFakeFactory();
        $fakeDiscount = $this->fakeDiscount();
        $mockProduct = $this->fakeProduct();
        $stubFactory->shouldReceive('createProductTransfomer')->passthru();

        $mockProduct->shouldReceive('setDiscount')->once()->with($fakeDiscount);

        $transfomer->doSomething($fakeDiscount, $mockProduct);
    }

            // now lets make sure that doSomething returns what the call to factory's createProductTransformer method returns
    function test_doSomething_createProductTransformerCalledWithProductAndClosureReturnsValue_ReturnsSameValue()
    {
        list($transformer, $stubFactory) = $this->makeTransfomerWithFakeFactory();
        $fakeDiscount = $this->fakeDiscount();
        $fakeProduct = $this->fakeProduct();
        $stubFactory->shouldReceive('createProductTransfomer')->andReturn('transformed result');

        $result = $transfomer->doSomething($fakeDiscount, $fakeProduct);

        $this->assertEquals('transformed result', $result);
    }

}

【讨论】：