fix: prevent silent session fallback in interactive PTY mode#21
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Claude Code's --resume flag behaves differently in interactive mode vs -p mode:
- In -p mode: properly errors when session doesn't exist
- In interactive mode: silently falls back to most recent session
This caused Codez sessions to sometimes switch to a different Claude session
when the stored session was no longer on disk (cleaned up, path changed, etc).
Add claudeSessionExistsOnDisk() utility to check if ~/.claude/projects/{path-hash}/{id}.jsonl
exists before spawning the PTY with --resume. If the session doesn't exist,
fall back to --session-id (create fresh) instead, avoiding silent fallback.
Includes comprehensive tests for path hashing and session file detection.
Before spawning an interactive PTY with --resume, verify that the Claude session still exists on disk. If not found, use --session-id to create a fresh session instead of letting Claude silently fall back to the most recent session. Logs a warning when a stale session is detected and recovered.
Expand test-clear-session-id.mjs with three new tests: - Test 5: Proves --resume with non-existent UUID silently falls back in interactive mode (the root cause of the session-switching bug) - Test 6: Validates that --session-id with existing UUID errors - Test 7: Confirms --session-id behavior in interactive mode These tests demonstrate the distinction between -p and interactive modes and document the expected behavior when session validation is in place.
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dakl
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Summary
Fixed a bug where Codez sessions would silently switch to a different Claude Code session when resuming.
Root cause: Claude Code's
--resumeflag behaves differently in interactive mode vs-pmode:When a stored Claude session was no longer on disk (cleaned up, path changed, etc), interactive
--resume <missing-id>would fall back instead of error, causing users to see a completely different conversation.Solution
Added
claudeSessionExistsOnDisk()utility to validate that~/.claude/projects/{path-hash}/{session-id}.jsonlexists before spawning an interactive PTY with--resume. If the session file is missing, fall back to--session-id(create fresh) instead, preventing the silent fallback.The fix also logs a warning when a stale session is detected and recovered.
Changes
Testing
All 223 unit tests pass. New tests validate:
--resume <bad-uuid>silently falls back in interactive mode (the bug)Related earlier work:
🤖 Generated with Claude Code