claude-print/notes/bf-2f1.md

Phase 8: Emitter — Completion Notes (bf-2f1)

Status

Phase 8 implementation was already present in commit bfb50da (Add Phase 8: Emitter). Two bead runs verified correctness; all 13 tests confirmed passing on each run.

Verification

All 13 emitter unit tests pass:

• test_text_correct_string_trailing_newline — text format emits {response}\n
• test_text_no_extra_whitespace — no leading/trailing whitespace beyond newline
• test_json_valid_with_required_fields — all required fields present in JSON output
• test_json_claude_version_included — claude_version field emitted
• test_json_usage_fields_are_integers — usage token counts are integers not strings
• test_error_result_is_error_true_and_subtype — error JSON has correct structure
• test_error_exit_code_nonzero — all error variants produce non-zero exit codes
• test_error_subtypes — subtype strings match plan spec
• test_error_exit_codes — exit codes: Setup→2, Timeout→124, Interrupted→130, AssistantError→1
• test_text_error_goes_to_stderr_not_stdout — text-mode errors go only to stderr
• test_zero_token_counts_when_fallback — fallback path produces all-zero usage object
• test_stream_json_each_line_parses_as_json — forwarded JSONL lines are valid JSON
• test_stream_json_disconnect_exits_immediately — reader thread exits cleanly on disconnect

Implementation Summary

src/emitter.rs (~185 LOC) provides:

• emit_success() — routes to text/json/stream-json format output
• emit_error() — structured error output by format; text-mode errors to stderr only
• StreamJsonHandle — holds mpsc drain channel + thread join handle
• spawn_stream_json_reader() / spawn_stream_json_reader_to() — testable reader thread
• stream_json_reader_loop() — tails transcript JSONL from start_offset, forwards lines to stdout; retries file open if transcript not yet present; exits cleanly on drain signal or channel disconnect