Add option to add additional directories to generate.cache snapshot

[weotch]

Is your feature request related to a problem? Please describe.

We often use nuxt in a yarn workspace based monorepo like:

/library
/nuxt-app
  /nuxt.config.js
/shopify-theme
yarn.lock

When we push a commit up to Netlify and there is only changes to the library directory, we'll see a message like this in the deploy log:

11:03:26 AM: [success] Skipping webpack build as no changes detected

When nuxt-app depends on those changes to library, this means that the new build doesn't contain the fresh code change.

Describe the solution you'd like

I think this could be fixed with a nuxt.config.js option to provide our own patterns to globby here:

https://github.com/nuxt/nuxt.js/blob/853439ddf945b6ee358d5912e6e5a68009633c27/packages/cli/src/utils/generate.js#L162-L167

Since globby supports an array for its first argument, I think we could pass a value like:

await globby(['**/*.*', '../library/**/*.*'], {
  ...
}

Describe alternatives you've considered

We could move the rootDir out to the parent.

[IsraelOrtuno]

This is specially needed for monorepo applications. Could be great to be able to specify other folders from the nuxt.config.js file.

@weotch have you found an alternative? I have been dealing with this for a while now.

[IsraelOrtuno]

@weotch and others, I solved this issue by adding a symlink to that external folder.

  const coreCacheFolder = this.nuxt.options.srcDir + '/__libcache';

  this.nuxt.hook('generate:cache:ignore', () => {
    fs.symlink(path.resolve(__dirname, '../'), coreCacheFolder, 'dir', () => {});
  });

  this.nuxt.hook('generate:done', () => {
    if (!fs.existsSync(coreCacheFolder)) return;
    fs.unlinkSync(coreCacheFolder);
  });

In my case, this code is in a module file which is on the shared library folder and is that folder the one that contains a lot of reusable components. That's why I use ../. You could set there whatever path to your library folder.

Tested in localhost and Netlify. Working 👍