Mutant

A mutation testing library for Clojure.

tl;dr: Mutant breaks your code and lets you know if your test suite is still green.

Mutant tries to break your code. It goes through your namespaces and introduces changes to your sources. After each mutation it attempts to run your test suite. If all tests still pass despite the mutation Mutant reports the mutation as a survivor.

Usage

Add the lein-mutate to in the :plugins vector of either your :user profile or your project.clj. Make sure your test suite is green. Then run:

$ lein trampoline mutate

Learn more in the user's guide.

Documentation

The documentation lives in the doc directory. It's currently divided into two parts:

• the user's guide, and
• the contributor's guide.

Take a look, let me know what you think, and if anything is unclear feel free to submit patches!

Maturity status

Wildly experimental 🔥

Related work

• Markus Schirp's Mutant is a mutation testing tool for Ruby.
• Henry Coles' Pitest is a state of the art mutation testing system for the JVM.

License

Copyright 2016–now Jan Stępień <jan@stepien.cc>

Licensed under the Apache License, Version 2.0 (the "License"); you may
not use this file except in compliance with the License. You may obtain
a copy of the License at https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.