The expression return $this->getOptions($container, 'fixtures') returns the type array which is incompatible with the return type mandated by Zend\ServiceManager\Fact...ryInterface::__invoke() of object.
In the issue above, the returned value is violating the contract defined by the
mentioned interface.
Let's take a look at an example:
interfaceHasName{/** @return string */publicfunctiongetName();}className{public$name;}classUserimplementsHasName{/** @return string|Name */publicfunctiongetName(){returnnewName('foo');// This is a violation of the ``HasName`` interface// which only allows a string value to be returned.}}
This check looks for parameters that have been defined for a function or method, but which are not used in the method body.