Use GitHub Copilot as a testing and debugging partner, then verify its suggestions with evidence.
- Who is this for: Developers who know basic Python and want a more reliable Copilot-assisted workflow.
- What you'll learn: How to investigate unfamiliar code, design focused tests, find missing edge cases, diagnose a failure, and critically review AI-assisted changes.
- What you'll build: A tested and corrected bill-splitting library that never loses or invents a cent.
- Prerequisites:
- Getting Started with GitHub Copilot, or equivalent familiarity with Copilot Chat
- Basic Python, Git, and terminal experience
- Access to GitHub Copilot and GitHub Codespaces or VS Code
- How long: This exercise takes less than 45 minutes to complete.
In this exercise, you will:
- Explain unfamiliar code and record a debugging hypothesis.
- Generate focused tests from explicit behavior requirements.
- Add edge cases that Copilot did not initially consider.
- Use a failing test to diagnose, fix, and refactor the implementation.
- Review the final diff and document how you verified Copilot's suggestions.
Simply copy the exercise to your account, then give your favorite Octocat (Mona) about 20 seconds to prepare the first lesson, then refresh the page.
Having trouble? 🤷
When copying the exercise, we recommend the following settings:
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For owner, choose your personal account or an organization to host the repository.
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We recommend creating a public repository, since private repositories will use Actions minutes.
If the exercise isn't ready in 20 seconds, please check the Actions tab.
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Check to see if a job is running. Sometimes it simply takes a bit longer.
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If the page shows a failed job, please submit an issue. Nice, you found a bug! 🐛
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