Function runProcessCapture

plugins/plugin-eval/src/core/benchmark.js:246–299

({
  command,
  args,
  cwd,
  env,
  stdoutPath,
  stderrPath,
})

}

async function runProcessCapture({
  command,
  args,
  cwd,
  env,
  stdoutPath,
  stderrPath,
}) {
  const startedAt = Date.now();
  const child = spawn(command, args, {
    cwd,
    env,
    stdio: ["ignore", "pipe", "pipe"],
  });

  const stdoutChunks = [];
  const stderrChunks = [];

  if (child.stdout) {
    child.stdout.on("data", (chunk) => {
      stdoutChunks.push(chunk);
    });
  }

  if (child.stderr) {
    child.stderr.on("data", (chunk) => {
      stderrChunks.push(chunk);
    });
  }

  const outcome = await new Promise((resolve, reject) => {
    child.once("error", reject);
    child.once("close", (code, signal) => {
      resolve({ code: code ?? 1, signal });
    });
  });

  const stdoutText = Buffer.concat(stdoutChunks).toString("utf8");
  const stderrText = Buffer.concat(stderrChunks).toString("utf8");

  if (stdoutPath) {
    await writeText(stdoutPath, stdoutText);
  }
  if (stderrPath) {
    await writeText(stderrPath, stderrText);
  }

  return {
    ...outcome,
    durationMs: Date.now() - startedAt,
    stdoutText,
    stderrText,
  };
}

function buildObservedUsageLine(target, scenario, usage) {
  return JSON.stringify({