Function appendTraces

e2e/src/trace-harvest.ts:28–36

(runDir: string, entries: ReadonlyArray<TraceEntry>)

const fileFor = (runDir: string) => join(runDir, "traces.json");

export const appendTraces = (runDir: string, entries: ReadonlyArray<TraceEntry>): void => {
  if (entries.length === 0) return;
  const file = fileFor(runDir);
  const existing: TraceEntry[] = existsSync(file)
    ? (JSON.parse(readFileSync(file, "utf8")) as TraceEntry[])
    : [];
  const merged = [...existing, ...entries].sort((a, b) => a.at - b.at);
  writeFileSync(file, JSON.stringify(merged, null, 1));
};