Is jest not running ServerStream? about browser-bunyan

[philmander]

Hi Jon, the jest test that exists is a unit test. A good unit test should not rely on any external dependencies like a server. Instead, it overrides the behavior of XMLHttpRequest to mock expected server behavior.

Look for MockXMLHttpRequest in https://github.com/philmander/browser-bunyan/blob/master/packages/server-stream/test/server-stream.test.js

[philmander]

I also just realized that ServerStream's unit test doesn't actually run on Jest, but another testing framework, Tap.

[9bits]

Yeah, I was had set up jest mocks but the assert for XMLHttpRequest kept failing. I realized that ServerStream wasn't getting used when the test was run when I checked if the endpoint was getting hit

[philmander]

Do you still need some help with this?

[9bits]

Yeah, I'm still wondering if it's possible to use jest to test this use case.
I'm also trying to figure out why jest doesn't even try to initialize ServerStream.

[philmander]

I originally thought you were trying to write a Jest based test for ServerStream directly, but I think you are trying to test your code that uses a logger configured to use ServerStream. You have to options:

• To proceed with your current approach, you need to globally mock XMLHttpRequest. Maybe there's some issues around doing this in Jest, I'm not sure
• I would alternatively recommend that you find a way to completely mock your Bunyan logger in your tests or a logger without any Streams added