Carbon object add and subtract methods don’t return a fresh instance
When debugging API calls made using Guzzle, which usually truncates the error message in the log, catch the exception and use $e->getResponse()->getBody()->getContents() to see what the hell is going on. However, it seems to be possible for getResponse() to return null when the request fails.
Constructor parameters can be passed to Mockery using \Mockery::mock(Mockable::class, array($param));
In PHPUnit, you can use the @doesNotPerformAssertions test to simply run a method and test it does not throw an exception without the test being marked ‘risky’
When testing multiple similar cases, consider using a data provider to populate the test fixture. Particularly good for testing validation and authorization