Laravel - HTTP Tests -

In the example above, you may have noticed we invoked the etc method at the end of our assertion chain. This method informs Laravel that there may be other attributes present on the JSON object. If the etc method is not used, the test will fail if other attributes that you did not make assertions against exist on the JSON object.

The intention behind this behavior is to protect you from unintentionally exposing sensitive information in your JSON responses by forcing you to either explicitly make an assertion against the attribute or explicitly allow additional attributes via the etc method.