Muter

Muter is an automated mutation testing tool for Swift, inspired by Stryker, PIT and Mull.

It can be run within Xcode, where mutants are shown in the editor to rapidly find areas where test code can be improved, or from the command line, which gives detailed information about the health and quality of the whole test suite and can be used in CI. Muter changes operators and removes statements in the code, runs the tests for each mutant and computes a mutation score per file and for the project.

Muter is free and open source under the MIT licence.