Await the Completion of a Readable Stream ES8 TypeScript, fs

My code isn't working because the file hasn't unzipped before the next line executes. This is my function for unzipping:

import { createGunzip } from 'zlib';
import { createReadStream, statSync, createWriteStream } from 'fs';

function fileExists(filePath: string) {
  try {
    return statSync(filePath).isFile();
  } catch (err) {
    return false;
  }
}

async function gunzipFile(source: string, destination: string): Promise<void> {
  if (!fileExists(source)) {
    console.error(`the source: ${source} does not exist`);
    return;
  }
  const src = createReadStream(source);
  const dest = createWriteStream(destination);
  await src.pipe(createGunzip())
    .pipe(dest)
    .on('error', (error) => {
      // error logging
    })
    .on('end', () => {
      return;
    });
}

How would I refactor this to get it to properly work asynchronously? Or non-async if it'll wait before completing. There are similar questions but they don't work for me, perhaps because this function returns void, not the data that has been streamed.

src.pipe not return a Promise then you can not wait on it. Let's convert it into a Promise:

function gunzipFile(source: string, destination: string): Promise<void> {
  if (!fileExists(source)) {
    console.error(`the source: ${source} does not exist`);
    return;
  }
  const src = createReadStream(source);
  const dest = createWriteStream(destination);

  return new Promise((resolve, reject) => { // return Promise void
    src.pipe(createGunzip())
      .pipe(dest)
      .on('error', (error) => {
        // error logging
        // reject(error); // throw error to outside
      })
      .on('finish', () => {
        resolve(); // done
      });
  })
}