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🗺️Coverage

TestGap

Finds untested code paths after every commit — before they become production bugs.

TestGap diffs your latest commit against your test suite and surfaces exactly which new code paths have no test coverage. Run it in CI and ship with confidence that nothing slipped through.

View on GitHub ↗
$pip install testgap
testgap — zsh
testgap --commit HEAD --suite tests/

/ the problem

Coverage % is a lie. 80% coverage means 20% of your code is untested.

Overall coverage numbers hide where the gaps are. TestGap shows you the exact functions, branches, and lines added in this commit that have zero test coverage — so you fix the gap before it ships.

/ how it works

Four steps. One command.

1
📝

Diff the commit

Identifies every new function, branch, and line added in the latest commit

2
🔬

Map to tests

Cross-references against your test suite to find what's covered and what isn't

3
🗺️

Generate gap report

Outputs a ranked list of untested paths by risk — highest-impact gaps first

4

Suggest tests

Claude generates test stubs for the top gaps, ready to paste into your test file

/ use cases

When to reach for TestGap

Pre-merge coverage gates in CI
Finding gaps in payment and auth flows
New engineer onboarding — map what's tested
Audit before a major release

Ready to use TestGap?

MIT licensed. One command install. Works in CI today.

$pip install testgap
Full docs on GitHub ↗

/ stay in the loop

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