debug-failing-test

Debug a failing unit test by iteratively adding verbose logging, running the test, and analyzing the output until the root cause is found and fixed. ## Workflow ### Phase 1: Initial Assessment 1. **Run the failing test** to capture the current error message and stack trace 2. **Read the test file** to understand what is being tested 3. **Read the source file** being tested to understand the expected behavior 4. **Identify the assertion that fails** and what values are involved ### Phase 2: Iterative Debugging Loop Repeat until the root cause is understood: 1. **Add verbose logging** around the suspicious code: - Use `console.log('[DEBUG]', ...)` with descriptive labels - Log input values, intermediate states, and return values - Log before/after key operations - Add timestamps if timing might be relevant 2. **Run the test** and capture output 3. **Assess the logging output:** - What values are unexpected? - Where does the behavior diverge from expectations? - What additional logging would help narrow down the issue? 4. **Decide next action:** - If root cause is clear → proceed to fix - If more information needed → add more targeted logging and repeat ### Phase 3: Fix and Verify 1. **Implement the fix** based on findings 2. **Run the test** to verify it passes 3. **Run related tests** to ensure no regressions ### Phase 4: Clean Up 1. **Remove ALL debugging artifacts:** - Delete all `console.log('[DEBUG]', ...)` statements added - Remove any temporary variables or code added for debugging - Ensure the code is in a clean, production-ready state 2. **Verify the test still passes** after cleanup ### Phase 5: Document and Learn 1. **Provide a summary** to the user (1-3 sentences): - What was the bug? - What was the fix? 2. **Record the learning** by following the learning instructions (if you have them): - Extract a single, clear learning from this debugging session - Add it to the "Learnings" section of the most relevant instruction file - If a similar learning already exists, increment its counter instead ## Logging Conventions When adding debug logging, use this format for easy identification and removal: ```typescript console.log('[DEBUG] <location>:', <value>); console.log('[DEBUG] before <operation>:', { input, state }); console.log('[DEBUG] after <operation>:', { result, state }); ``` ## Example Debug Session ```typescript // Added logging example: console.log('[DEBUG] getEnvironments input:', { workspaceFolder }); const envs = await manager.getEnvironments(workspaceFolder); console.log('[DEBUG] getEnvironments result:', { count: envs.length, envs }); ``` ## Notes - Prefer targeted logging over flooding the output - Start with the failing assertion and work backwards - Consider async timing issues, race conditions, and mock setup problems - Check that mocks are returning expected values - Verify test setup/teardown is correct