Laravel 5.2 – 为foreach()提供的参数无效 – 使用phpunit

public function testProductCreationFailsWhenNameNotProvided()
{
    $product = factory(AppProduct::class)->make(['name' => '']);

    $this->post(route('api.products.store'),$product->jsonSerialize())
        ->seeJson(['name' => ['The name field is required.']]) /*line 86*/
        ->assertResponseStatus(422);
}

完整的错误报告在这里：

There was 1 error:
1) ExampleTest::testProductCreationFailsWhenNameNotProvided
ErrorException: Invalid argument supplied for foreach()
C:xampphtdocsproduct-  servicevendorlaravelframeworksrcIlluminateSupportArr.php:494
C:xampphtdocsproduct-servicevendorlaravelframeworksrcIlluminateFoundationTestingConcernsMakesHttpRequests.php:231
C:xampphtdocsproduct-servicevendorlaravelframeworksrcIlluminateFoundationTestingConcernsMakesHttpRequests.php:257
C:xampphtdocsproduct-servicetestsExampleTest.php:86
C:xamppphppearPHPUnitTextUICommand.php:176
C:xamppphppearPHPUnitTextUICommand.php:129
FAILURES!
Tests: 7,Assertions: 43,Errors: 1.

我承认这段代码原本不是我的 – 它是从Laravel教程复制的.它在那里工作得很好.
不幸的是,这个相关问题的答案也没有帮助我.
Laravel 5.1 + PHPunit – API test returns always invalid argument error foreach

我试图修改它以传递json数组作为参数

public function testProductCreationFailsWhenNameNotProvided()
    {
        $product = factory(AppProduct::class)->make(['name' => '']);

        $this->post(route('api.products.store'),$product->jsonSerialize())
            ->seeJson(json_encode(array('name' => ['The name field is required.'])))
            ->assertResponseStatus(422);
    }

但后来我收到了这个错误：

1) ExampleTest::testProductCreationFailsWhenNameNotProvided
TypeError: Argument 1 passed to IlluminateFoundationTestingTestCase::seeJson() must be of the type array,string given,called in C:xampphtdocsproduct-servicetestsExampleTest.php on line 86