debtcollector/doc/source/examples.rst

Examples

Moving a method

To move a instance method from an existing one to a new one the :py~debtcollector.moves.moved_method function/decorator can be used to achieve this in a non-destructive manner.

A basic example to do just this:

>>> from debtcollector import moves >>> import warnings >>> warnings.simplefilter('always') >>> class Cat(object): ... @moves.moved_method('meow') ... def mewow(self): ... return self.meow() ... def meow(self): ... return 'kitty' ... >>> c = Cat() >>> c.mewow() __main__:1: DeprecationWarning: Method 'Cat.mewow()' has moved to 'Cat.meow()' 'kitty' >>> c.meow() 'kitty'

Moving a property

To move a instance property from an existing one to a new one the :py~debtcollector.moves.moved_property function/decorator can be used to achieve this in a non-destructive manner.

A basic example to do just this:

>>> from debtcollector import moves >>> import warnings >>> warnings.simplefilter('always') >>> class Dog(object): ... @property ... @moves.moved_property('bark') ... def burk(self): ... return self.bark ... @property ... def bark(self): ... return 'woof' ... >>> d = Dog() >>> d.burk __main__:1: DeprecationWarning: Property 'Dog.burk' has moved to 'Dog.bark' 'woof' >>> d.bark 'woof'

Moving a class

To move a class from an existing one to a new one the :py~debtcollector.moves.moved_class type generator function can be used to achieve this in a non-destructive manner.

A basic example to do just this:

>>> from debtcollector import moves >>> import warnings >>> warnings.simplefilter('always') >>> class WizBang(object): ... pass ... >>> OldWizBang = moves.moved_class(WizBang, 'OldWizBang', __name__) >>> a = OldWizBang() __main__:1: DeprecationWarning: Class '__main__.OldWizBang' has moved to '__main__.WizBang' >>> b = WizBang()

Renaming a keyword argument

To notify the user when a keyword argument has been replaced with a new and improved keyword argument and the user is still using the old keyword argument the :py~debtcollector.renames.renamed_kwarg function/decorator can be used to achieve this in a non-destructive manner.

A basic example to do just this:

>>> from debtcollector import renames >>> import warnings >>> warnings.simplefilter('always') >>> @renames.renamed_kwarg('snizzle', 'nizzle') ... def do_the_deed(snizzle=True, nizzle=True): ... print(snizzle) ... print(nizzle) ... >>> do_the_deed() True True >>> do_the_deed(snizzle=False) __main__:1: DeprecationWarning: Using the 'snizzle' argument is deprecated, please use the 'nizzle' argument instead False True >>> do_the_deed(nizzle=False) True False

Further customizing the emitted messages

It is typically useful to tell the user when a deprecation has started and when the deprecated item will be offically removed (deleted or other). To enable this all the currently provided functions this library provides take a message, version and removal_version keyword arguments. These are used in forming the message that is shown to the user when they trigger the deprecated activity.

A basic example to do just this:

>>> from debtcollector import renames >>> import warnings >>> warnings.simplefilter('always') >>> @renames.renamed_kwarg('snizzle', 'nizzle', version="0.5", removal_version="0.7") ... def do_the_deed(snizzle=True, nizzle=True): ... pass ... >>> do_the_deed(snizzle=False) __main__:1: DeprecationWarning: Using the 'snizzle' argument is deprecated in version '0.5' and will be removed in version '0.7', please use the 'nizzle' argument instead

If the removal_version is unknown the special character ? can be used instead (to denote that the deprecated activity will be removed sometime in the future).

A basic example to do just this:

>>> from debtcollector import renames >>> import warnings >>> warnings.simplefilter('always') >>> @renames.renamed_kwarg('snizzle', 'nizzle', version="0.5", removal_version="?") ... def do_the_deed(snizzle=True, nizzle=True): ... pass ... >>> do_the_deed(snizzle=False) __main__:1: DeprecationWarning: Using the 'snizzle' argument is deprecated in version '0.5' and will be removed in a future version, please use the 'nizzle' argument instead

To further customize the message (with a special postfix) the message keyword argument can be provided.

A basic example to do just this:

>>> from debtcollector import renames >>> import warnings >>> warnings.simplefilter('always') >>> @renames.renamed_kwarg('snizzle', 'nizzle', message="Pretty please stop using it") ... def do_the_deed(snizzle=True, nizzle=True): ... pass ... >>> do_the_deed(snizzle=False) __main__:1: DeprecationWarning: Using the 'snizzle' argument is deprecated, please use the 'nizzle' argument instead: Pretty please stop using it