# Bead bf-3ag: Session struct and version resolution

## Task Summary

Create `src/session.rs` with:
- SessionResult struct with transcript, claude_version, duration_ms
- run() function signature with all parameters
- Version resolution: Command::new(claude_bin).arg("--version").output()
- Add pub mod session to lib.rs
- Unit test test_version_resolution mocks claude --version output

## Status: Already Completed

The work for this bead was completed in previous commits:
- `557a810 feat(session): implement Session struct and version resolution`
- `de4d914 test(session): fix version resolution test and add struct validation test`

## Re-verification: 2026-06-13

All acceptance criteria remain satisfied:
- ✅ session.rs compiles
- ✅ SessionResult struct with all required fields (transcript, claude_version, duration_ms)
- ✅ run() function with all parameters implemented
- ✅ Version resolution using Command::new(claude_bin).arg("--version").output()
- ✅ pub mod session in lib.rs
- ✅ Unit test test_version_resolution_with_mock_binary passes
- ✅ cargo test passes (4/4 session tests)

## Verification

All requirements have been verified:

1. ✅ **SessionResult struct** - Lines 22-29 in src/session.rs
   - Contains `transcript: TranscriptResult`
   - Contains `claude_version: String`
   - Contains `duration_ms: u64`

2. ✅ **run() function** - Lines 55-248 in src/session.rs
   - Takes `claude_bin: &Path`
   - Takes `claude_args: &[OsString]`
   - Takes `prompt: Vec<u8`
   - Takes `timeout_secs: Option<u64>`
   - Returns `Result<SessionResult>`

3. ✅ **Version resolution** - Lines 251-268 in src/session.rs
   - Uses `Command::new(claude_bin).arg("--version").output()`
   - Parses stdout/stderr for version string
   - Returns trimmed first line

4. ✅ **Module export** - Line 10 in src/lib.rs
   - Contains `pub mod session;`

5. ✅ **Unit tests pass** - All 4 session tests pass:
   - `test_resolve_claude_version_with_nonexistent_binary` ✅
   - `test_session_result_struct_has_required_fields` ✅
   - `test_resolve_claude_version_with_echo` ✅
   - `test_version_resolution_with_mock_binary` ✅

## Test Output

```
running 4 tests
test session::tests::test_resolve_claude_version_with_nonexistent_binary ... ok
test session::tests::test_session_result_struct_has_required_fields ... ok
test session::tests::test_resolve_claude_version_with_echo ... ok
test session::tests::test_version_resolution_with_mock_binary ... ok

test result: ok. 4 passed; 0 failed; 0 ignored; 0 measured
```

## Conclusion

The bead requirements are fully satisfied by the existing implementation. No additional code changes are required.