mutation-testing

Evaluate Python test suite quality using mutmut to introduce code mutations and verify tests catch them. Use for mutation testing, test quality assessment, mutant detection, and test effectiveness analysis.

1.17x

Quality

77%

Does it follow best practices?

Impact

87%

1.17x

Average score across 3 eval scenarios

Securityby

Passed

No known issues

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Evaluation results

72%

19%

Setting Up Mutation Testing for a Python Payment Library

mutmut configuration setup

Criteria

Without context

With context

Correct tool section

100%

paths_to_mutate set to src/

70%

backup=False

runner uses pytest with -x flag

100%

runner uses -x flag specifically

100%

tests_dir configured

90%

100%

mutmut installed via pip

50%

25%

Run command documented

100%

Results command documented

100%

dict_synonyms option present

No absolute paths in config

100%

91%

-9%

Evaluating and Strengthening Tests for an Inventory Library

Run mutation testing and fix test gaps

Criteria

Without context

With context

mutmut run executed

100%

mutmut results used

100%

mutmut show used

100%

50%

Survived mutants listed

100%

Boundary condition tests added

100%

Edge case tests: empty/None/zero

100%

Actual return values verified

100%

All branches covered

100%

Mutation score reported

100%

Report explains test gaps

100%

Missing SKU edge case tested

100%

No large temp files

100%

37%

100%

29%

Adding Mutation Testing to a Python Project's CI Pipeline

GitHub Actions CI integration for mutation testing

Criteria

Without context

With context

Triggered on pull_request

100%

paths filter on src/**

100%

actions/checkout used

100%

actions/setup-python used

100%

Python version 3.10

100%

mutmut and pytest installed

100%

mutmut run --CI flag used

100%

mutmut results step present

100%

ubuntu-latest runner

100%

--CI flag explained in notes

100%

paths filter explained in notes

100%

Workflow file in correct location

100%

Repository: mixpanel/mixpanel-headless
Commit: 3ce3191

Evaluated: 2 days ago
Agent: Claude Code
Model: Claude Sonnet 4.6

Table of Contents

Setting Up Mutation Testing for a Python Payment Library Evaluating and Strengthening Tests for an Inventory Library Adding Mutation Testing to a Python Project's CI Pipeline

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