Yarn workspaces: nohoist exclude

问题

In my package.json, I currently have

"workspaces": {
  "nohoist": **
}

I would like to specify JUST TWO packages to hoist, and nohoist on everything else. Is there a simple way to do this without pasting all of my packages except those two into nohoist?

回答1:

After days of digging I ended up with the following configuration.

Yarn seems to use some kind of Bash glob pattern matching (see this Linux journal article for a tutorial). In this configuration the "nohoist" rule disables hoisting for every module whose virtual path ends with one of the strings in the list. Sadly Yarn interprets the string as a prefix so that also modules like "my-site-whatever" and "someones-components-whatever" match, but this can be dealt with.

{
  "private": true,
  "version": "independent",
  "workspaces": {
    "packages": [ "packages/**/*" ],
    "nohoist": [  
      "**/!(my-site|my-cms|someones-components)"
     ]
  },
  "scripts": {
    "postinstall": "yarn workspace @myscope/my-site link --link-folder $PWD/node_modules @someone/someones-components"
  }
}

I included in this example also a postinstall script which is out of topic but shows how we can establish a symbolic link to a sibling package after the dependencies have been installed. Upon install, Yarn Workspaces creates a symbolic link to each package in workspace root /node_modules. We can take an advantage of that and use one of those links to effortlessly create a wanted symlink in a package, by pointing yarn link's --link-folder parameter to /node_modules at the workspace root.

This assumes that @myscope/my-site/package.json has a declared dependency on @someone/someones-components. That dependency can be added with the command

yarn workspace @myscope/my-site add @someone/someones-components

Because @someone/someones-components is configured for hoisting in our workspace root package.json, it is at Yarn's discretion to install it in /node_modules at the workspace root, not under the package private node_modules. Also, if @someone/someones-components has been downloaded into /packages/@someone/someones-components, it is matched by our packages directive "packages/**/*" and not downloaded into /node_modules either, but rather symlinked like so:

/node_modules/@someone/someones-components -> ../../packages/@someone/someones-components

Which is perfect. The only thing we need to do is to keep the postinstall script up to date to have required symlinks available in dependent packages. I think we could also automatically look up the dependencies in the script and establish the links.

Search keywords: monorepo lerna (not needed)