In Python, how do I indicate I’m overriding a method?

by

Based on this and fwc:s answer I created a pip installable package https://github.com/mkorpela/overrides

From time to time I end up here looking at this question.
Mainly this happens after (again) seeing the same bug in our code base: Someone has forgotten some “interface” implementing class while renaming a method in the “interface”..

Well Python ain’t Java but Python has power — and explicit is better than implicit — and there are real concrete cases in the real world where this thing would have helped me.

So here is a sketch of overrides decorator. This will check that the class given as a parameter has the same method (or something) name as the method being decorated.

If you can think of a better solution please post it here!

def overrides(interface_class):
    def overrider(method):
        assert(method.__name__ in dir(interface_class))
        return method
    return overrider

It works as follows:

class MySuperInterface(object):
    def my_method(self):
        print 'hello world!'


class ConcreteImplementer(MySuperInterface):
    @overrides(MySuperInterface)
    def my_method(self):
        print 'hello kitty!'

and if you do a faulty version it will raise an assertion error during class loading:

class ConcreteFaultyImplementer(MySuperInterface):
    @overrides(MySuperInterface)
    def your_method(self):
        print 'bye bye!'

>> AssertionError!!!!!!!

More Related Contents:

  1. Overriding properties in python
  2. Python Method overriding, does signature matter?
  3. Force child class to override parent’s methods
  4. What does ‘super’ do in Python? – difference between super().__init__() and explicit superclass __init__()
  5. How do I call a parent class’s method from a child class in Python?
  6. Calling parent class __init__ with multiple inheritance, what’s the right way?
  7. How to “perfectly” override a dict?
  8. How to invoke the super constructor in Python?
  9. How can I dynamically create derived classes from a base class
  10. Cast base class to derived class python (or more pythonic way of extending classes)
  11. Subclassing int in Python
  12. inheritance from str or int
  13. Inheritance of private and protected methods in Python
  14. Why aren’t superclass __init__ methods automatically invoked?
  15. Python super() raises TypeError
  16. Overriding “+=” in Python? (__iadd__() method)
  17. TypeError: Cannot create a consistent method resolution order (MRO) [duplicate]
  18. Should all Python classes extend object? [duplicate]
  19. Which classes cannot be subclassed?
  20. List all base classes in a hierarchy of given class?
  21. How to call Base Class’s __init__ method from the child class? [duplicate]
  22. Python inheritance – how to disable a function
  23. Overriding append method after inheriting from a Python List
  24. How do I override a Python import?
  25. Calling superclass constructors in python with different arguments
  26. The inheritance of attributes using __init__
  27. How to remove a field from the parent Form in a subclass?
  28. Accessing attribute from parent class inside child class
  29. Inheritance and init method in Python
  30. Python: Inheritance versus Composition

Leave a Comment