Fix card source expiry date update

[ob-stripe]

r? @dpetrovics-stripe (dev-platform run)
cc @stripe/api-libraries

Fixes an issue where the library failed to update the expiry date when updating a card source.

[grey-stripe]

LGTM

[arcanedev-maroc]

I think this PR is a breaking change because it replace Stripe\Card to Stripe\AttachedObject object.

Skipped: https://github.com/stripe/stripe-php/blob/master/lib/Util/Util.php#L81

Try to var_dump($source->card) to see the result.

cc: @ob-stripe

[ob-stripe]

The card hash under source objects does not have an "object" => "card" entry (because it's not a card object), so convertToStripeObject() would not convert those hashes to \Stripe\Card objects but just to a generic \Stripe\Object.

You're correct that this patch did cause the type to be changed from \Stripe\Object to \Stripe\AttachedObject, which might be seen as a breaking change, but I have a hard time thinking of a practical case where that would break anything. What do you think?

[arcanedev-maroc]

Try to add this test in TokenTest class to see the issue:

/** @test */
public function it_can_create_card_token()
{
    $token = self::createCardToken();

    $this->assertInstanceOf(Token::class, $token);
    $this->assertSame('card', $token->type);

    $this->assertInstanceOf(Card::class, $token->card);
    $this->assertSame('Visa', $token->card->brand);
}

/**
  * Create a card Token for tests
  *
  * @return Token
  */
private static function createCardToken()
{
    return Token::create([
        'card' => [
            'number'    => '4242424242424242',
            'exp_month' => date('n'),
            'exp_year'  => date('Y') + 1,
            'cvc'       => '314',
        ]
    ]);
}

[ob-stripe]

Ah, indeed, the card hash nested in token objects is an actual card object, and this patch does cause the regression you described.

I'll try to push a fix shortly.

[arcanedev-maroc]

Can you try to remove/revert only this line and see if the tests passes ?

If it passes, you can close #396 without merging

[ob-stripe]

That would make your new test pass, but cause the test I added in this PR to fail (i.e. it would make it impossible to update expiry dates on card sources).