Code · Tests

AI unit test generator — coverage in seconds

Paste a function or class and Muse writes unit tests for it — happy paths, edge cases and failures — in Jest, Vitest, pytest, JUnit and other common frameworks.

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Example

Tests that think about edge cases

Tests mode covers normal inputs, boundaries, invalid data and error paths — and names each test so failures are easy to read.

Jest, Vitest, Mocha, pytest, unittest, JUnit and more
Edge cases and error paths included
Mocks for network and time when needed
Ask for more cases or a different framework

Muse · Code · Tests · Jest

Write tests for avg(xs) that returns 0 for empty arrays.

test("empty → 0", () => expect(avg([])).toBe(0));
test("single value", () => expect(avg([5])).toBe(5));
test("negatives", () => expect(avg([-2, 2])).toBe(0));
test("floats", () => expect(avg([0.1, 0.2])).toBeCloseTo(0.15));

How to use it

Tests in three steps

Switch to Code

Open Muse and tap Code in the mode switcher.

Pick “Tests”

Choose the task and, optionally, the language.

Paste and send

Paste your code or describe what you need — then ask follow-ups.

Try these prompts

Things to ask

Write pytest tests for this classAdd edge-case tests for this parserMock fetch in these Jest testsJUnit 5 tests for this service

FAQ

Tests: common questions

Which test frameworks does Muse use?

It picks the common framework for your language (for example Jest for JavaScript, pytest for Python, JUnit for Java). Ask for a specific one if you prefer.

Will the tests pass?

Muse writes tests for the behavior it sees in your code. Run them — failures often reveal real bugs or unclear requirements.

Can it write integration tests?

It can draft them, but unit tests for focused functions give the best results.

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