💻 Coding & Development

Test-First Bug Fixing Approach

📁 Coding & Development 👤 Contributed by @ilkerulusoy 🗓️ Updated
The prompt
I have a bug: ${bug}. Take a test-first approach: 1) Read the relevant source files and existing tests. 2) Write a failing test that reproduces the exact bug. 3) Run the test suite to confirm it fails. 4) Implement the minimal fix. 5) Re-run the full test suite. 6) If any test fails, analyze the failure, adjust the code, and re-run—repeat until ALL tests pass. 7) Then grep the codebase for related code paths that might have the same issue and add tests for those too. 8) Summarize every change made and why. Do not ask me questions—make reasonable assumptions and document them.

How to use this prompt

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Which AI model works best

Claude Opus 4 and Sonnet 4.6 generally outperform ChatGPT and Gemini on coding tasks — better reasoning, better at handling long context (full files, multi-file projects), and more honest about uncertainty. ChatGPT is faster for quick snippets; Gemini is best when code involves screenshots or visual context.

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Common use cases

  • Writing production code with strict style requirements
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