Wordsmith a comment.
Rename variable expects to expects_method
Write a function with attributes as if it were a class.

Using a function to create another function with a surrounding
closure containing variables is similar to a class with instance
variables.
Replace class ExpectsMethod with a function with closure.
Extract build_expects_method.is_reserved_method_name()
Extract build_expects_method.is_mock_method()
Rename build_expects_method() to new_ExpectsMethod().

This is supposed to look consistent with new ClassName().
Rename build_mock_method() with new_MockMethod()
Replace mock_method.expectations with mock_method.create_expectation()
Pull creation of expectations out of ExpectationList
Rename methods in ExpectationList and MockMethodList to be consistent.
Rename MockFunction.check_mock_usage() to check_usage()
Rename ExpectsMethod.check_expects_usage() to check_usage()