getJSMainModuleName automatically adds `.js`

[atrauzzi]

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• [✔] Search for existing issues: https://github.com/facebook/react-native/issues
• [✔] Use the latest React Native release: https://github.com/facebook/react-native/releases

Environment

  React Native Environment Info:
    System:
      OS: Windows 10
      CPU: (8) x64 Intel(R) Core(TM) i7-4770K CPU @ 3.50GHz
      Memory: 6.39 GB / 15.94 GB
    Binaries:
      Yarn: 1.12.1 - C:\Users\atrauzzi\AppData\Roaming\npm\yarn.CMD
      npm: 6.4.1 - C:\Program Files\nodejs\npm.CMD

Description

I'm using TypeScript in my project, so if I want to change my entrypoint, setting getJSMainModuleName to the path of a TypeScript file (with a .ts or .tsx extension) results in something like src/Path/To/File.ts.js.

Reproducible Demo

Any generic React Native project with TS configured. Edit here.

[rickhanlonii]

Hey @atrauzzi, thanks for filing - this file has to be a javascript file, we can't use a typescript file for this

[atrauzzi]

@rickhanlonii - Why not just resolve it as a module and let babel take care of what you get?

[rickhanlonii]

@atrauzzi in prod, when this code is run this code has already been transpiled so you couldn't require the ts.