claude-print/notes/bf-1en.md

bead bf-1en: transcript.rs Implementation Verification

Task

Implement src/transcript.rs: JSONL transcript parsing

Status: VERIFICATION COMPLETE ✓

The implementation was already complete in commit c6241e3:

• src/transcript.rs implements full JSONL parsing
• tests/transcript.rs has 18 comprehensive tests

Implementation Summary

Core Functionality (src/transcript.rs)

1. Data Structures

   • Usage: Token counts (input, output, cache_creation, cache_read)
   • AggregatedUsage: Running totals across all turns
   • ContentBlock: Text, ToolUse, Thinking, Unknown
   • AssistantMessage: Message with ID, content blocks, usage
   • ResultEvent: Session ID and error status
   • Event: Discriminating union (Assistant, User, Result, Unknown)
   • TranscriptResult: Final output with text, usage, metadata

2. parse_transcript(path)

   • Reads JSONL file line-by-line
   • Extracts text from ContentBlock::Text blocks only
   • Deduplicates streaming chunks by message.id or usage fingerprint
   • Aggregates token counts across all unique turns
   • Extracts session_id and is_error from Result events
   • Handles missing files → empty result
   • Silently skips malformed lines

3. read_transcript(path, last_assistant_message)

   • Retry loop: 40 × 50ms = 2s budget
   • Handles Stop-before-JSONL race window
   • Falls back to last_assistant_message if retries exhausted
   • Returns error if both are empty

Test Coverage (tests/transcript.rs)

All 18 tests pass:

• Single turn, single text block
• Multi-block content (text + tool_use + thinking)
• Multi-turn with unique keys
• Streaming dedup (5 chunks → 1 turn)
• Token aggregation (45 turns)
• Missing/null cache tokens
• Unknown event types and content blocks
• Malformed JSONL lines
• Empty files
• Usage-fingerprint fallback (no message.id)
• Result event fields
• Fallback to last_assistant_message
• Race conditions (MOCK_DELAY_JSONL)

Verification

$ cargo test --lib transcript
test result: ok. 3 passed

$ cargo test --test transcript
test result: ok. 18 passed

All tests pass. Implementation matches AGENTS.md specification.

Bead Closure

The bead is closed after this verification. No code changes were needed as the implementation was already complete.