[doctor] check if native files in local Expo modules are being ignored

[keith-kurak]

Why

An issue we've run into a few times is where someone creates a local module, but set their gitignore file to ignore their app's native project folders, but they made that match too greedy, so it ignores all android and ios folders.

The errors can be a little confusing when this happens... you'll get all the way to Fastlane and it'll be like, "I can't find this Cocoapod".

Matches like /ios or ios/** are fine, but ios is not.

How

Check for:
a) does the modules folder exist?
b) if so, do any files match modules/**/ios/*.podspec or modules/**/android/buld.gradle?
c) if so, are any of those files gitignored?

Optimally, I'd check .easignore, as well, but this should catch most cases. AFAIK, checking .easignore would require reading the file and using minimatch, so a completely different mechanism than the existing gitignore check, which is pretty thorough because it uses git check-ignore from the top level. A good long-term goal would be to refactor into a general-purpose ignore check that reports back what exactly is ignoring a file and can be used by multiple checks..

Test Plan

Checklist

• Documentation is up to date to reflect these changes (eg: https://docs.expo.dev and README.md).
• Conforms with the Documentation Writing Style Guide
• This diff will work correctly for npx expo prebuild & EAS Build (eg: updated a module plugin).

[byCedric]

Awesome, nice to see the tests too!