Preserve values across test re-runs in Watch mode

[anthumchris]

How can we persist values across test runs that occur in Watch mode? For example, I'd like to

1. run Ava in watch mode
2. instantiate and store a value when Ava runs test for the first time
3. modify a test file
   1. (Ava re-runs the test file)
4. The test will fetch the pre-existing value.

My use case is creating a pool of Puppeteer pages that can quickly be obtained and worked with. These pages take > 5s to authenticate and load, and I'd like the Puppeteer browser and created pages to be reused to avoid the instantiation times.

[novemberborn]

This would be possible using the experimental shared workers feature.

Keep in mind though that test files run in fresh contexts, so you won't be able to directly share the Puppeteer API.

[anthumchris]

I will look into the shared workers. My current workaround is to launch Chrome with a debugging port and use puppeteer.connect() to connect to that. This allows Chrome to stay open and maintain existing page authentications.

$ "/Applications/Google Chrome.app/Contents/MacOS/Google Chrome" --remote-debugging-port=9222

import puppeteer from 'puppeteer-core'

puppeteer.connect({
  browserURL: 'http://127.0.0.1:9222/json/version',
  ...
})

[novemberborn]

That looks an approach that would work with shared workers as well.