Add assertContainsElement

[jackbayliss]

This PR introduces a new assertion method: assertContainsElement.

It acts as a shorthand for assertElementExists, making it easier to chain assertions directly off a component/view or response keeping it fluent and great for quick, simple checks without sacrificing expressiveness.

So, all you do is the selector and the attributes.

$this->view('testing')
    ->assertContainsElement('nav');
    ->assertContainsElement('span.foo', ['text' => 'Foo', 'class' => 'bar foo'])

The idea being, for simple assertions such as alert banners etc, we can just do the below, as sometimes using assertElementExists feels long:

$this->view('testing')
    ->assertContainsElement('div.banner', ['text' => 'Your item was created successfully', 'class' => 'success']);

I will probably add an assertDoesntContainElement if this gets accepted

I've added it to the ide-helper, and improved the component dom to match the other nesting items.

[sinnbeck]

Thanks for all of these PR's. Its great to see some interest in expanding on the package.
Sorry that it takes me a while to review them, but I have a bit hung up in my personal life currently :)

Any reason why the ide-helper.php has been changed from TestResponse to TestComponent ?

[jackbayliss]

@sinnbeck no problem!

The reason I changed the stan return is the TestComponent macro returns $this - which is actually TestComponent not TestResponse.

I think I copy pasted when I first added them 😬 - so fixing my own mistake. ( I guess there might be a few others wrong too, but will sort in a separate PR)

[sinnbeck]

@jackbayliss Ok I might need to test it out. I think I originally set it to TestResponse as that allows phpstorm to autocomplete after it. For instance

$this->get('/foo')
    ->assertContainsElement('nav')
    ->assertStatus(200); //this can be autocompleted

[jackbayliss]

@sinnbeck Sure, we can revert those changes for now if you want - I'm not too precious about it :)

[sinnbeck]

@jackbayliss I think it might be a matter of whether we are asserting on a view or a response. I wonder if it is possible to make both work. Perhaps a union value is what is needed.

        public function assertElement($selector = 'body', $callback = null)
        {
            /** @var \Illuminate\Testing\TestComponent|\Illuminate\Testing\TestResponse $instance */
            return $instance;
        }

I am thinking it might be best to revert it in this PR, and we can look into a version that works for both in a seperate?

[sinnbeck]

Sorry. Just read the code again. I think yours is 100% correct. But a separate PR would be nice if you dont mind? :)