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Introduction

Codecrumbs is a Python library (and pytest plugin) for source code refactoring across library boundaries. It allows you to change the API of your library and to propagate this changes to every one who uses your library.

The invocation of deprecated API is detected at runtime and fixes can be generated.

This removes the pain of fixing upstream API changes manually. The developer can now rename all the functions who need an better name without to fear that he drives his users crazy because they have to fix thousands of lines of code. This saves valuable developer time. However it is not 100% save and the refactoring may break your code (see Limitations)

Note

codecrumbs is currently limited to refactor attribute names and function argument names, but more options are planned.

Requirements

codecrumbs requires Python 3.8, 3.9 or 3.10.

Limitations

  • expressions inside identical code blocks in the same line can not be fixed. 

    lambdas = (lambda a: x, lambda a: x)
lists = all(len(e) > 5 for e in l1) and all(len(e) > 5 for e in l2)

  • fixing deprecations inside doctests is currently not supported for python 3.11.

I'm currently working on the migration to executing. It will take some time, but I hope to remove some of these limitations.

Installation

Install or add codecrumbs as a dependency to your library::

pip install codecrumbs

This includes the pytest plugin which allows the user of your library to fix the deprecated API calls without to install additional libraries.

Quick Start

Annotate your refactoring first

import codecrumbs


class Example:
    # cfgmod was renamed to config_module
    cfgmod = codecrumbs.renamed_attribute("config_module")

    def config_module(self, some_arg):
        print("some code", some_arg)

Calling cfgmod now triggers an DeprecationWarning and redirects to config_module

You can fix code which is using cfgmod in two ways:

  • If you have tests for your code which calling the deprecated API:

    pytest --codecrumbs-fix test_of_your_code.py

  • if you have a small script without tests.

    codecrumbs run your_script.python