React Native naming collision error when running packager, caused by “lodash” and “yeoman-generator”

Question

Description

In my project I am using "react-native": "0.36.0" and among the dependencies:

• "lodash": "^4.15.0"
• "yeoman-generator": "^0.24.1"

When using versions higher than "^3.10.1" for "lodash" and "0.21.2" for "yeoman-generator" I get naming collisions on "lodash" , "inquirer" and "cli-width" when running packager.

Reproduction

Have the dependencies described above and run: react-native start --reset-cache

Result:

jest-haste-map: @providesModule naming collision:
Duplicate module name: inquirer
  Paths: /CoolProject/node_modules/react-native/node_modules/yeoman-generator/node_modules/inquirer/package.json collides with /CoolProject/node_modules/react-native/node_modules/inquirer/package.json

This warning is caused by a @providesModule declaration with the same name across two different files.
jest-haste-map: @providesModule naming collision:
  Duplicate module name: lodash
  Paths: /CoolProject/node_modules/react-native/node_modules/lodash/package.json collides with /CoolProject/node_modules/react-native/node_modules/inquirer/node_modules/lodash/package.json

This warning is caused by a @providesModule declaration with the same name across two different files.
jest-haste-map: @providesModule naming collision:
  Duplicate module name: cli-width
  Paths: /CoolProject/node_modules/react-native/node_modules/yeoman-generator/node_modules/cli-width/package.json collides with /CoolProject/node_modules/react-native/node_modules/cli-width/package.json

This warning is caused by a @providesModule declaration with the same name across two different files.

Solution

Using the same versions for "lodash" and "yeoman-generator" as the ones used in react-native@0.36.0 (ie "^3.10.1" for "lodash" and "0.21.2" for "yeoman-generator" ) fixes the issue, but changing them is really not an option for me at the moment, especially because "yeoman-generator" is the dependency of another dependency. Is there any other possible fix?

Thanks!

Update

More details about this issue can be found in the react-native Gihub issue I posted: https://github.com/facebook/react-native/issues/11200

Update 2

Upgrading react-native to 0.39 solves the problem. The actual fix seems to be the removal of the apparently unused (and maybe outdated) yeoman-generator dependency: https://github.com/facebook/react-native/commit/1fd7a574ba538d05da4be841c84a70766464ec13

Answer 1

This usually happens when you switch from npm to yarn when installing modules or setting up projects using React Native. A simple npm install will usually close this issue without damaging your project's configuration.

npm install will notify you some of your modules are either deprecated or set up on a different version from the React Native ones and do what it takes to fix it. Also, if you wish to really clean up your configuration, notice the npm WARN gentlyRm warnings about packages that are put aside but not removed.