Do you want to request a feature or report a bug?
feature request

What is the current behavior?
Currently yarn why won't indicate any package info in the resolutions field

If the current behavior is a bug, please provide the steps to reproduce.

1. install a package with any version, e.g "pkg": "^1.0.0"
2. add resolutions field in package.json, pkg: "1.0.0"
3. update "pkg": "^1.0.0" to "pkg": "^2.0.0" in deps
4. run yarn why pkg

It only displays "pkg": "^2.0.0" being used, but no info about pkg: "1.0.0", while in yarn.lock, can find pkg: "1.0.0" related info

What is the expected behavior?
expect to display resolutions package info as well

Please mention your node.js, yarn and operating system version.
yarn: 1.16.0
macOS
node: 8.16.0