[0.56.0-rc-2] Decorator support broken

Environment

Run react-native info in your terminal and paste its contents here.

React Native Environment Info:
    System:
      OS: macOS High Sierra 10.13.4
      CPU: x64 Intel(R) Core(TM) i7-7820HQ CPU @ 2.90GHz
      Memory: 148.02 MB / 16.00 GB
      Shell: 5.3 - /bin/zsh
    Binaries:
      Node: 8.11.2 - /usr/local/bin/node
      Yarn: 1.6.0 - /usr/local/bin/yarn
      npm: 6.1.0 - /usr/local/bin/npm
      Watchman: 4.9.0 - /usr/local/bin/watchman
    SDKs:
      iOS SDK:
        Platforms: iOS 11.3, macOS 10.13, tvOS 11.3, watchOS 4.3
    IDEs:
      Android Studio: 3.0 AI-171.4443003
      Xcode: 9.3.1/9E501 - /usr/bin/xcodebuild
    npmPackages:
      react: ^16.3.2 => 16.4.1
      react-native: ^0.56.0-rc.2 => 0.56.0-rc.2
    npmGlobalPackages:
      eslint-plugin-react-native: 3.2.1
      react-native-cli: 2.0.1
      react-native-git-upgrade: 0.2.7

Description

After upgrading to RN56, I am receiving a red screen for error:(...node-modules/react-native-Libraries/react-native/react-native-implementation.js: Cannot find module 'react-native-stage-0/decorator-support'.... My .babelrc file is as follows and worked on previous versions:

{
  "presets": [
  	"react-native",
  	"react-native-stage-0/decorator-support"
  ],
  "plugins": [
    "transform-decorators-legacy"
  ],
  "sourceMaps": true
}

Dev deps in package.json

  "devDependencies": {
    "babel-eslint": "^8.2.3",
    "babel-jest": "21.2.0",
    "babel-preset-react-native": "5.0.2",
    "babel-preset-react-native-stage-0": "^1.0.1",
    "eslint": "^4.19.1",
    "eslint-plugin-eslint-comments": "^2.0.2",
    "eslint-plugin-flowtype": "^2.49.3",
    "eslint-plugin-jest": "^21.17.0",
    "eslint-plugin-prettier": "^2.6.0",
    "eslint-plugin-react-native": "^3.2.1",
    "jest": "21.2.1",
    "react-test-renderer": "^16.4.1"
  },

Reproducible Demo

Use provided .babelrc on a 0.56.0-rc2 project

react-native init example --version="0.56.0-rc.2"
cd ./example
yarn add --dev babel-preset-react-native-stage-0

[jshearer]

I solved this by using

"babel-plugin-transform-decorators-legacy": "^1.3.5",

and

"plugins": [
    "transform-decorators-legacy",
]

In my .babelrc file.

[fwh1990]

@jshearer

No, you should install @babel/plugin-proposal-decorators for babel 7. The plugin you use was for babel 6

And babel had change it’s package prefix to @babel since babel-7-beta.4. You can see babel github here