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Intermediate
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Testing
Coding

Write Automated Tests for an Untested Codebase

Add meaningful test coverage to legacy or untested code in a single focused session — without reading every line first.

Time Required

2–4 hrs depending on codebase size

Expected Result

A test suite with 60%+ coverage on your core functions, with unit and integration tests running in CI.

Recommended Tools

1

Analyze the Codebase Structure

Open the project in Cursor and ask it to map the codebase — identify the key modules, public functions, and external dependencies that matter most to test.

Cursor
2

Prioritize Test Targets

Ask Claude to rank which functions need tests most urgently based on business risk, complexity, and how often they change — focus on the top 20.

Claude
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3

Generate Unit Tests

For each priority function, use GitHub Copilot inside your IDE to generate unit tests. Review each test to ensure it covers edge cases, not just the happy path.

GitHub Copilot
Cursor
4

Write Integration Tests

Use Cursor to write integration tests for the critical user paths — the sequences of function calls that deliver core product value.

Cursor
5

Fix Failures and Set Up CI

Run the test suite, fix any failures by asking Cursor to explain and correct them, then set up a GitHub Actions workflow using Copilot to run tests on every PR.

Cursor
GitHub Copilot
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