No longer possible to disable autolinking for specific platforms

[tido64]

Environment

System:
    OS: macOS 11.6.5
    CPU: (16) x64 Intel(R) Core(TM) i9-9980HK CPU @ 2.40GHz
    Memory: 23.41 GB / 64.00 GB
    Shell: 5.8 - /bin/zsh
  Binaries:
    Node: 14.19.0 - /private/var/folders/qc/zygl93h53zb3ctbyw0f0jbzm0000gn/T/xfs-ac3821f8/node
    Yarn: 3.1.1 - /private/var/folders/qc/zygl93h53zb3ctbyw0f0jbzm0000gn/T/xfs-ac3821f8/yarn
    npm: 8.6.0 - /usr/local/bin/npm
    Watchman: 2022.03.21.00 - /usr/local/bin/watchman
  Managers:
    CocoaPods: 1.11.3 - /usr/local/bin/pod
  SDKs:
    iOS SDK:
      Platforms: DriverKit 21.2, iOS 15.2, macOS 12.1, tvOS 15.2, watchOS 8.3
    Android SDK: Not Found
  IDEs:
    Android Studio: 2021.1 AI-211.7628.21.2111.8193401
    Xcode: 13.2.1/13C100 - /usr/bin/xcodebuild
  Languages:
    Java: 11.0.15 - /usr/bin/javac
  npmPackages:
    @react-native-community/cli: Not Found
    react: 17.0.2 => 17.0.2
    react-native: ^0.66.4 => 0.66.4
    react-native-macos: ^0.66.14 => 0.66.55
  npmGlobalPackages:
    *react-native*: Not Found

Description

According to the docs, it is possible to disable autolinking for certain platforms:

cli/docs/autolinking.md

Lines 73 to 86 in c4179d8

	## How can I customize how autolinking works for my package?
	A library can add a `react-native.config.js` configuration file, which will customize the defaults, example:
	```js
	// react-native.config.js
	module.exports = {
	dependency: {
	platforms: {
	android: null, // disable Android platform, other platforms will still autolink if provided
	},
	},
	};
	```

However, this seems to no longer work.

This is what react-native config looks normally:

{
  "root": "/~/example",
  "reactNativePath": "/~/example/node_modules/react-native",
  "dependencies": {
    "react-native-test-app": {
      "root": "/~",
      "name": "react-native-test-app",
      "platforms": {
        "ios": {
          "sourceDir": "/~/example/ios",
          "folder": "/~",
          "pbxprojPath": "/~/ios/ReactTestApp.xcodeproj/project.pbxproj",
          "podfile": "/~/example/ios/Podfile",
          "podspecPath": "/~/ReactTestApp-DevSupport.podspec",
          "projectPath": "/~/ios/ReactTestApp.xcodeproj",
          "projectName": "ReactTestApp.xcodeproj",
          "libraryFolder": "Libraries",
          "sharedLibraries": [],
          "plist": [],
          "scriptPhases": [],
          "configurations": []
        },
        "android": null,
        "macos": null,
        "windows": null
      },
      "assets": [],
      "hooks": {},
      "params": []
    }
  }
}

If I change react-native.config.js to:

module.exports = {
  dependency: {
    platforms: {
      android: null,
    },
  },
};

The output becomes:

{
  "root": "/~/example",
  "reactNativePath": "/~/example/node_modules/react-native",
  "dependencies": {}
}

Reproducible Demo

git clone https://github.com/microsoft/react-native-test-app.git
cd react-native-test-app
yarn

# open react-native.config.js and add `android: null`

cd example
yarn react-native config

[tido64]

cc @thymikee

[thymikee]

I've noticed you're using RN 0.66 and yarn v3 with workspace setup. Does it also happen on RN 0.68? Would be great if you'd be able to check with the latest version of the CLI (v8), although I don't recall changes in this space. Did it work before some changes/upgrades?

[tido64]

I wonder if this has ever worked since the introduction of joi. Modifying the schema lets me continue, but it crashes inside the platform packages because they expect userConfig to be nonnull.

I've only noticed this just now because the native module regex was overly eager and picked up things it shouldn't have.

Do we consider this a regression, bug in docs, or a new feature to be implemented?

[thymikee]

Hm, I guess we documented a case that never actually worked, or haven't in a really long time. There's no test case for that as well. It should be supported though.

Btw, we also allow overwriting from the app/project level, if you need to get unblocked:

module.exports = {
  dependencies: {
    "react-native-test-app": {
      platforms: {
        ios: null,
      },
    },
  },
}

If all platforms are nulled it won't show the dependency at all

[tido64]

I kinda worked around it with typealiases 😛

In any case, I can probably take a look at this later. It works for macos and windows, so it's kinda weird that it would fail for android/ios.