Function toAsciicast

e2e/src/surfaces/cli.ts:45–74

(recording: Uint8Array)

/** terminal-control's JSONL recording → asciicast v2 (what asciinema plays). */
const toAsciicast = (recording: Uint8Array): string => {
  const events = new TextDecoder()
    .decode(recording)
    .split("\n")
    .filter(Boolean)
    .flatMap((line): AsciicastEvent[] => {
      // The PTY can be killed mid-write on teardown (e.g. a vitest timeout
      // interrupts the fiber), leaving a truncated final JSONL line. A line
      // that doesn't parse is one dropped frame, never a failed test: skip it
      // instead of throwing.
      // oxlint-disable-next-line executor/no-try-catch-or-throw -- boundary: lenient parse of a best-effort recording artifact
      try {
        return [JSON.parse(line) as AsciicastEvent];
      } catch {
        return [];
      }
    });
  const header = events.find((event) => event.type === "header");
  const lines = [
    JSON.stringify({ version: 2, width: header?.cols ?? 80, height: header?.rows ?? 24 }),
  ];
  // One streaming decoder so multi-byte UTF-8 split across events survives.
  const decoder = new TextDecoder();
  for (const event of events) {
    if (event.type !== "output") continue;
    const text = decoder.decode(Uint8Array.from(event.bytes ?? []), { stream: true });
    if (text) lines.push(JSON.stringify([(event.at_ms ?? 0) / 1000, "o", text]));
  }
  return `${lines.join("\n")}\n`;
};

// acquireUseRelease so a vitest timeout (fiber interruption) still tears the
// PTY down instead of leaking the child process.