Environment details

• OS: Windows 10 (my machine) and Ubuntu 18.04 (GitHub Action runner)
• Node.js version: 12.14
• npm version: 6.14.5
• @google-cloud/pubsub version: 2.4.0
• Typescript version: 3.9.7

Steps to reproduce

1. Import anything from @google-cloud/pubsub@2.4.0 (e.g. Message), and use it
2. Run the code
3. The following error will occur:

TypeError: Cannot read property 'Reader' of undefined

  at ../node_modules/@google-cloud/pubsub/build/protos/protos.js:28:29
  at ../node_modules/@google-cloud/pubsub/build/protos/protos.js:22:26
  at Object.<anonymous> (../node_modules/@google-cloud/pubsub/build/protos/protos.js:24:3)
  at Object.<anonymous> (../node_modules/@google-cloud/pubsub/src/index.ts:156:1)

Minimal reproduction:

import { Message } from '@google-cloud/pubsub';

describe('Test', () => {
  it('should work', () => {
    expect(Message).toBeDefined();
  });
});

I had a look through the diff between 2.3.0 and 2.4.0, but couldn't see anything suspect. I did try downgrading my Typescript version to 3.8.3 to match what this library was compiled with, but the same error occurs