Overview

ook - Python-version-sensitive monkeypatching

Author: Zero Piraeus
Contact: z@etiol.net

ook is a simple library to assist with monkeypatching Python methods and functions on a per-Python-version basis. It provides one decorator, patch, which conditionally patches callables depending on which version of Python is running.

Example

Adding the compress() function to Python 2.6's itertools module:

import itertools
from ook import patch

# http://docs.python.org/2.7/library/itertools.html#itertools.compress

@patch(itertools, 2.6)
def compress(data, selectors):
    # compress('ABCDEF', [1,0,1,0,1,1]) --> A C E F
    return (d for d, s in itertools.izip(data, selectors) if s)

Usage

patch accepts an arbitrary number of version arguments, in a variety of formats:

@patch(some.module.or.class, 2.7, "2.6.8", (3, 2, 5), 3)
def method_or_function(signature):
    """Do something."""
    pass

... as well as min and max keyword arguments:

@patch(some.module.or.class, min="2.6.5", max=2.7)
def method_or_function(signature):
    """Do something."""
    pass

... which can be combined:

@patch(some.module.or.class, "3.2.5", max=3.2)
def method_or_function(signature):
    """Do something."""
    pass

Note: If you specify both keyword and non-keyword version arguments, the patch will only take effect if both the explicitly specified versions and the implied version ranges are satisfied.

With no arguments other than the module or class to be patched, patch applies the patch regardless of Python version:

@patch(some.module.or.class)
def method_or_function(signature):
    """Do something, no matter what."""
    pass

Installation

This should do the trick:

pip install ook