Fix: conditional exports types

[emmercm]

I do not know why, but Jest + TypeScript will not run without this change. The error it will give is:

  ● Test suite failed to run

    index.ts:1:47 - error TS7016: Could not find a declaration file for module '@metalsmith/collections'. '<redacted>/metalsmith-plugins/node_modules/@metalsmith/collections/lib/index.cjs' implicitly has an 'any' type.
      Try `npm i --save-dev @types/metalsmith__collections` if it exists or add a new declaration (.d.ts) file containing `declare module '@metalsmith/collections';`

    1 import collections, { CollectionConfig } from '@metalsmith/collections';
                                                    ~~~~~~~~~~~~~~~~~~~~~~~~~

I'd love to embed this plugin inside a new one, but I'm entirely blocked on this change, unfortunately.

[webketje]

Thx! I had a look at your tsconfig.json and will test myself after the weekend, but could it be related to this? https://stackoverflow.com/questions/70296652/how-can-i-use-exports-in-package-json-for-nested-submodules-and-typescript#answer-74485520

What happens when moduleResolution is set to Node?

This is big, because if this works better I would make that change for all core plugins

[emmercm]

Fascinating, "moduleResolution": "node" does solve the problem as well. I should note that tsc doesn't appear to be affected by this, only Jest, so it may be something to do with jest-resolve or ts-jest or something else.

I need to convert some of my tests to use @metalsmith/collections instead of metalsmith-auto-collections and metalsmith-collections. But it looks like I'm not making use of any other core plugins within my plugins monorepo, and I haven't converted https://github.com/emmercm/www to TypeScript yet.

Do you have a list of other core plugins I can help test?

[webketje]

This also seems related: microsoft/TypeScript#52363, and the change to make looks safe/ backwards-compatible so I think this can be added to all core plugins. To your question, the most important ones are @metalsmith/: markdown, permalinks, collections, layouts, in-place, sass, postcss, js-bundle, requests