# Mojo Test Runner

> Run Mojo tests using mojo test command. Use when executing tests or verifying test coverage.

- Skill: `majiayu000/mojo-test-runner-2` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add majiayu000/mojo-test-runner-2`
- Raw SKILL.md: https://api.skillmd.com/api/skills/majiayu000/mojo-test-runner-2/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: majiayu000 (https://skillmd.com/u/majiayu000)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/majiayu000/mojo-test-runner-2

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# Mojo Test Runner Skill

Execute Mojo tests with filtering and reporting.

## When to Use

- Running Mojo test suites
- Verifying implementation correctness
- TDD red-green-refactor cycle
- Checking test coverage before PR

## Quick Reference

```bash
# Run all tests
mojo test tests/

# Run specific file
mojo test tests/test_tensor.mojo

# Run with verbose output
mojo test -v tests/

# Run tests matching pattern
./scripts/run_tests.sh tensor
```

## Workflow

1. **Run tests** - Execute `mojo test` or script
2. **Review output** - Check pass/fail summary
3. **Fix failures** - Address failing tests
4. **Re-run tests** - Verify all pass

## Mojo-Specific Notes

- Test functions must start with `test_`
- Test files must match `test_*.mojo` or `*_test.mojo`
- Tests run independently - no shared state between tests
- Use `raises` keyword for exception testing

## Error Handling

| Error | Cause | Solution |
|-------|-------|----------|
| `Import error` | Module not found | Verify `-I` include paths |
| `Syntax error` | Invalid test code | Fix syntax before testing |
| `Timeout` | Test too slow | Optimize or increase timeout |
| `Memory error` | Ownership issue | Check ownership and borrowing |

## References

- `.claude/shared/mojo-anti-patterns.md` - Common test mistakes
- `/notes/review/` - Testing strategy documentation