Hi @sabrinaluo,

according to https://yarnpkg.com/lang/en/docs/selective-version-resolutions/ it is only meant for subdependencies, not the toplevel dependencies as these would be normally set in the lockfile.

which lets you define custom package versions inside your dependencies through the resolutions field in your package.json file. Normally, this would require manual edits in the yarn.lock file.

Try the following example and yarn why supports-color:

{
  "name": "yarn-pkg-test",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "dependencies": {
    "chalk": "^2.4.2"
  },
  "resolutions": {
    "chalk/supports-color": "5.3.0"
  }
}

Thanks to your quick response. @DanielRuf

Yes I understand it's for sub-dependencies, but there might be users make mistakes like me, so it would be great if this can be improved.

The case I encountered is having styled-components 3.4.x as dependency while a sub-dependency rebass requires styled-components 3.2.x. Instead resolutions: {rebass/styled-components: 3.2.x}, it's my bad to put resolutions: { "styled-components": "3.2.x"}. When starting the app, UI is always broken, say 'there might be two copy of styled-component', so I ran yarn why styled-components, only 3.4.x was listed. I was so confused where the other styled-components came from and spent a lot of time to investigate until I searched in yarn.lock, then figured out it's the resolutions.

So this is a feature request?

Yes, should be a feature request. Updated the issue type 😃 @DanielRuf

I first thought it's a bug. However, after your explanation, I understand it's not a bug yarn itself but most likely a mistake by users.

Maybe we could handle this by checking "if a resolution does not contains a wildcard * or a / then print a warning"? I'm not sure if having a resolution without one of those is really ever a valid use case...

I'm also going to rename this issue to make it more indicative of the feature request.

Hi can I take this up?

can I take this up?

Sure, do you need help with creating a PR or do you know the needed steps?