[5.6] Improve session errors assertions

[roberto-aguilar]

In the previous implementation of TestResponse::assertSessionHasErrors i found that was not possible to find errors that had an integer key, for example:

// If somewhere in your application you did
return redirect()->back()->withErrors('Something wrong happened.')

// You ended up with a message bag similar to this one in the session errors
$errors = new Illuminate\Support\MessageBag('Something wrong happened.');
$errors->get(0); // Returns 'Something wrong happened.'

// And the following assertion was failing, even when the error was there
$this->post('/somewhere')
     ->assertSessionHasErrors(['Something wrong happened.']);

This was happening because if the assertion detected that the key was an integer, it was sending the error value to the MessageBag::has method, which was incorrect because that method uses the key to determine if there is any messages for it.

Also, as part of the refactor i achieved the following assertion API improvements, which now allow to find:

/*
 * All the messages for a given key
 */
$this->post('/somewhere', ['password' => 'abc 123'])
     ->assertSessionHasErrors([
         'password' => [
             'The password may only contain letters, numbers, and dashes.',
             'The password must be at least 8 characters.',
         ],
     ]);

/*
 * A subset of the messages for a given key
 */
$this->post('/somewhere', ['password' => 'abc 123'])
     ->assertSessionHasErrors([
         'password' => [
             'The password must be at least 8 characters.',
         ],
     ]);

/*
 * An specific message for a given key (without the need for a wrapping array).
 */
$this->post('/somewhere', ['password' => 'abc 123'])
     ->assertSessionHasErrors([
         'password' => 'The password must be at least 8 characters.',
     ]);

/*
 * Messages with integer keys
 */
$this->post('/somewhere')
     ->assertSessionHasErrors([
         'Something wrong happened.',
         'And this happened too.',
     ]);

/*
 * A subset of messages with integer keys
 */
$this->post('/somewhere')
     ->assertSessionHasErrors([
         'Something wrong happened.',
     ]);

/*
 * An specific message with an integer key (without the need for a wrapping array).
 */
$this->post('/somewhere')
     ->assertSessionHasErrors('Something wrong happened.');

[carusogabriel]

👍 for 5.6

[taylorotwell]

Are there any breaking changes in this PR at all @DojoGeekRA?

[roberto-aguilar]

Hi @taylorotwell,

No, there are no breaking changes, the previous API still works 😃

[roberto-aguilar]

@carusogabriel yeah, i have no problem with that, but i though that the LTS users could still benefit from this 😄

Thanks for the suggestion!

[taylorotwell]

Actually broke the most simple use case of this function.

[taylorotwell]

Feel free to re-submit with tests proving this actually works.

[roberto-aguilar]

I'm sorry @taylorotwell i tried several scenarios but missed the one with just the error key.

Thanks for the help, i have been working on this and will submit again when is ready 😃