fix: properly serialize Error objects in debug logs #117
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Error objects logged with logger.debug() were appearing as {} because
JSON.stringify() doesn't capture non-enumerable Error properties (message,
stack, name).
Added serializeForLog() helper that explicitly extracts Error properties,
making debug logs actually useful for diagnosing issues like "Process
exited unexpectedly".
Before: [16:21:21.424] [remote]: launch error {}
After: [16:21:21.424] [remote]: launch error {"name":"Error","message":"...","stack":"..."}
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Craig van Heerden <craig@example.com>
- docs/debugging/exit-code-1-investigation.md: Full technical investigation - scripts/reproduce-crash.mjs: Minimal reproduction script Key finding: Crash is Happy-internal race condition, not Claude Code bug. Reproduction script stays alive 30+ seconds with identical flags. Generated with [Claude Code](https://claude.ai/code) via [Happy](https://happy.engineering) Co-Authored-By: Claude <noreply@anthropic.com> Co-Authored-By: Happy <yesreply@happy.engineering>
Root cause confirmed: Claude Code's "only prompt commands are supported in streaming mode" error when using --resume with --input-format stream-json. This is GitHub issue #16712 - Claude Code injects synthetic message before reading stdin, breaking the message chain. Added: - Confirmed root cause section - Potential workarounds - References to relevant docs Generated with [Claude Code](https://claude.ai/code) via [Happy](https://happy.engineering) Co-Authored-By: Claude <noreply@anthropic.com> Co-Authored-By: Happy <yesreply@happy.engineering>
…rror-serialization-in-logger
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Problem
When errors occur during session execution (e.g., "Process exited unexpectedly"), the actual error details are lost in the logs:
The error object appears as
{}becauseJSON.stringify()doesn't capture Error properties (message,stack,name) - they're not enumerable.Solution
Added a
serializeForLog()helper function that properly handles Error objects by explicitly extracting their non-enumerable properties.Before
After
Changes
serializeForLog()helper function insrc/ui/logger.tslogToFile()to use the new helpersendToRemoteServer()to use the same helper for consistencysrc/ui/logger.test.tsTesting
All 7 tests pass:
Impact
This fix will help users and maintainers debug "Process exited unexpectedly" errors by capturing the actual error details in logs at
~/.happy/logs/.🤖 Generated with Claude Code