Function getStream

src/test/helpers.ts:196–226

(stream: Readable, waitForPattern?: string | RegExp)

 * Will resolve early if
 */
export function getStream(stream: Readable, waitForPattern?: string | RegExp) {
  let resolve: (value: string) => void;
  const promise = new Promise<string>((res) => {
    resolve = res;
  });
  const received: Buffer[] = [];
  let combinedBuffer: Buffer = Buffer.concat([]);
  let combinedString: string = '';

  stream.on('data', (data) => {
    received.push(data);
    combine();
    if (
      (typeof waitForPattern === 'string' &&
        combinedString.indexOf(waitForPattern) >= 0) ||
      (waitForPattern instanceof RegExp && combinedString.match(waitForPattern))
    )
      resolve(combinedString);
    combinedBuffer = Buffer.concat(received);
  });
  stream.on('end', () => {
    resolve(combinedString);
  });

  return promise;

  function combine() {
    combinedBuffer = Buffer.concat(received);
    combinedString = combinedBuffer.toString('utf8');
  }
}

//#region Reset node environment