perf: skip getting package class name inside expo module

[szymonrybczak]

Summary:

Recently blog post regarding performance improvements inside autolinking was published, as it turns between implementations there's a big difference.

After my investigation it is due getting package class name from classes which are implementing ReactPackage or TurboReactPackage. In past we landed improvements to this logic (read more here).

But as mentioned in the blog post the difference is still big and the root cause of this issue is because of reading hundreds of files from expo modules and trying to find classes that implements ReactPackage or TurboReactPackage, but expo modules don't implement ReactPackage or TurboReactPackage directly inside their source code, so the return value will be anyway null, so it doesn't make sense to read hundreds of files and check for classes that implements ReactPackage or TurboReactPackage.

Inside this Pull Request I've added a early return if module is expo module, following logic doesn't affect output of config command because expo modules follows other rules and are included in native build in different way.

Exception is expo package itself which contains expo-module.config.json and also implements ReactPackage or TurboReactPackage, I added appropriate condition for this case.

Benchmark:

Tested on the react-conf-app.

Before:

❯ hyperfine 'node ~/development/cli/packages/cli/build/bin.js config'
Benchmark 1: node ~/development/cli/packages/cli/build/bin.js config
  Time (mean ± σ):      2.353 s ±  0.033 s    [User: 2.067 s, System: 0.313 s]
  Range (min … max):    2.313 s …  2.408 s    10 runs

After:

❯ hyperfine 'node ~/development/cli/packages/cli/build/bin.js config'
Benchmark 1: node ~/development/cli/packages/cli/build/bin.js config
  Time (mean ± σ):     654.7 ms ±  30.7 ms    [User: 453.2 ms, System: 269.3 ms]
  Range (min … max):   620.0 ms … 711.5 ms    10 runs

Test Plan:

1. Clone the repository and do all the required steps from the Contributing guide
2. Run this command:

node /path/to/react-native-cli/packages/cli/build/bin.js config

3. Output should be the same.

Checklist

• Documentation is up to date to reflect these changes.
• Follows commit message convention described in CONTRIBUTING.md

[cortinico]

LGTM. I'm just wondering if an expo module could actually have both the 'expo-module.config.json' file and an implementation of a ReactPackage. However I believe that's not the case