Package subpath './package.json' is not defined by "exports" #1168
Description
Environment
System:
OS: macOS 10.15.4
CPU: (4) x64 Intel(R) Core(TM) i7-5557U CPU @ 3.10GHz
Memory: 94.37 MB / 16.00 GB
Shell: 5.7.1 - /bin/zsh
Binaries:
Node: 14.2.0 - /usr/local/bin/node
Yarn: 1.22.4 - /usr/local/bin/yarn
npm: 6.14.4 - /usr/local/bin/npm
Watchman: 4.9.0 - /usr/local/bin/watchman
Managers:
CocoaPods: 1.9.1 - /usr/local/bin/pod
SDKs:
iOS SDK:
Platforms: iOS 13.4, DriverKit 19.0, macOS 10.15, tvOS 13.4, watchOS 6.2
Android SDK: Not Found
IDEs:
Android Studio: Not Found
Xcode: 11.4.1/11E503a - /usr/bin/xcodebuild
Languages:
Java: 1.8.0_121 - /usr/bin/javac
Python: 3.7.7 - /usr/local/opt/python/libexec/bin/python
npmPackages:
@react-native-community/cli: Not Found
react: 16.13.1 => 16.13.1
react-native: 0.62.2 => 0.62.2
npmGlobalPackages:
*react-native*: Not Found
Description
When running react-native under Node.js 14.x on a project that uses npm modules which specify the new exports field in package.json, react-native will print the following warning (in this example the uuid package is used):
warn Package uuid has been ignored because it contains invalid configuration. Reason: Package subpath './package.json' is not defined by "exports" in /PATH_TO_CURRENT_PROJECT/node_modules/uuid/package.json
The same issue has been reported in other places:
i18next-http-backend: Warning: Ignored package due to "Package subpath './package.json' is not defined by "exports"" facebook/react-native#28710 for (workaround: i18next/i18next-http-backend@1d8da79#diff-b9cfc7f2cdf78a7f4b91a753d10865a2R8)i18next-locize-backend: https://github.com/locize/i18next-locize-backend/pull/326/filesnanoevents: Importing error in React Native starting from nanoevents 3.0 version ai/nanoevents#44uuid: package.json is not defined by "exports" uuidjs/uuid#444 (comment)
The reason is that, starting in Node.js 14.x, as soon as an npm module defines the exports field in package.json, only the files listed there are exported. If package.json is not included in that list, it's no longer possible to do things like require.resolve('uuid/package.json');.
The problematic piece of code is:
cli/packages/cli/src/tools/config/resolveNodeModuleDir.ts
Lines 11 to 13 in 5819a17
For a package like uuid which does not contain react-native specific configuration in package.json this is not a problem, but for modules that do contain such config in package.json they will be forced to add package.json to their exports field.
An alternative would be to not rely on require.resolve and instead use https://github.com/browserify/resolve
As far as I know this is how rollup.js solves this issue, see rollup/plugins#208 (comment)
What is the maintainers take on this? Do you think that every single module on npm that starts making use of the exports field should include package.json in the exports? Or could this be fixed in react-native?
Reproducible Demo
- Use Node.js 14.x
npm i uuid@8.0.0- Open
noderepl:
> require.resolve('uuid/package.json');
Uncaught:
Error [ERR_PACKAGE_PATH_NOT_EXPORTED]: Package subpath './package.json' is not defined by "exports" in /PROJECT/node_modules/uuid/package.json
at applyExports (internal/modules/cjs/loader.js:491:9)
at resolveExports (internal/modules/cjs/loader.js:507:23)
at Function.Module._findPath (internal/modules/cjs/loader.js:635:31)
at Function.Module._resolveFilename (internal/modules/cjs/loader.js:1007:27)
at Function.resolve (internal/modules/cjs/helpers.js:78:19)
at repl:1:9
at Script.runInThisContext (vm.js:131:20)
at REPLServer.defaultEval (repl.js:436:29)
at bound (domain.js:429:14)
at REPLServer.runBound [as eval] (domain.js:442:12) {
code: 'ERR_PACKAGE_PATH_NOT_EXPORTED'
}