Function append

packages/simdeck-test/src/index.ts:832–837

(source: string, chunk: Buffer)

function captureChildOutput(child: ChildProcess): () => string {
  const chunks: string[] = [];
  const append = (source: string, chunk: Buffer) => {
    chunks.push(`[${source}] ${chunk.toString("utf8")}`);
    while (chunks.join("").length > 16_384) {
      chunks.shift();
    }
  };
  child.stdout?.on("data", (chunk: Buffer) => append("stdout", chunk));
  child.stderr?.on("data", (chunk: Buffer) => append("stderr", chunk));
  return () => chunks.join("").trim();