fix(iOS): Use REACT_NATIVE_PATH env to resolve react native path in Hermes podspec

[gabrieldonadel]

Summary:

On iOS, the REACT_NATIVE_PATH environment variable is set during both the CocoaPods installation process and the app build. Most React Native scripts already rely on this variable or provide a way to specify a custom React Native path (rather than relying on the default node_modules resolution).

However, the Hermes podspec currently does not support using REACT_NATIVE_PATH to determine the React Native version. This limitation creates issues in scenarios like Expo Go, where React Native is built from a submodule, making Hermes resolve an incorrect React Native version

Changelog:

[IOS] [CHANGED] - Use REACT_NATIVE_PATH env to resolve react native path in Hermes podspec

Test Plan:

Run pod install and build

[cipolleschi]

Hi @gabrieldonadel thanks for the PR.
I don't really like the idea of using an Env variable for this approach and I believe we can clean up the podspec in a better way.

the use_react_native! function receives the react_antive_path as a parameter.
Is this value set properly for Expo GO?

What we can do, instead of recomputing the react_native_path, is to set that value in a variable in the react_native_pods.rb file and then expose the variable so that it can be consumed by the hermes-engine.podspec file.

How does that sound like? Can you take care of updating the PR?

[gabrieldonadel]

Hi @gabrieldonadel thanks for the PR. I don't really like the idea of using an Env variable for this approach and I believe we can clean up the podspec in a better way.

the use_react_native! function receives the react_antive_path as a parameter. Is this value set properly for Expo GO?
Yeah, we use the react_native_path param, and it works for everything but the hermes podspec

What we can do, instead of recomputing the react_native_path, is to set that value in a variable in the react_native_pods.rb file and then expose the variable so that it can be consumed by the hermes-engine.podspec file.

How does that sound like? Can you take care of updating the PR?

This sounds great, let me update this PR