🐛 Knip does not resolve package.json exports quite correctly

[maastrich]

Prerequisites

• I'm using the latest version
• I've read the relevant documentation
• I've searched for existing issues
• I've checked the list of known issues
• I've read the issue reproduction guide

Reproduction url

maastrich/repro#2

Reproduction access

• I've made sure the reproduction is publicly accessible

Description of the issue

First, thanks for the amazing tool, it's really impressive how quick and effective knip is 👏

When setting up exports using glob syntax in the package.json, typescript can resolve * to be either a path part or multiple path part:

"./*": "./src/public/*/index.ts" // can resolve to
   -> "./src/public/foo/bar/index.ts"
   -> "./src/public/baz/index.ts"

but knip doesn't

For the moment I've found a workaround where I add this in my package.json so knip can resolve le path
(leaving both as typescript resolve the first one and knip the second)

"./*": "./src/public/*/index.ts",
+ "./**": "./src/public/**/index.ts",

[webpro]

Thanks for report. That's correct according to the Node.js docs and honestly I'm a bit baffled by it:

* maps expose nested subpaths as it is a string replacement syntax only.

All instances of * on the right hand side will then be replaced with this value, including if it contains any / separators.

From a Knip perspective, the issues I have with this:

• a lot more files might become entry files and this isn't great in terms of finding unused exports (which aren't reported by default in entry files)
• unsure about the performance penalty, Knip has to traverse the fs and find all matching files (a runtime does string replacement first and then starts resolution).
• people who'd be baffled like me might unintentionally use * thinking it actually means * in glob pattern matching, with subtly unexpected results both in exposed exported paths as in Knip analysis.

What about this workaround, would this work:

"./*": "./src/public/**/index.ts",

Just curious, not saying it's a solution.

[maastrich]

Unfortunately the workaround you proposed is not working with rollup (but typescript handles it)
I was more thinking about an option in the knip config as a "quick fix" saying

pkgJsonExport: "glob" | "node";

where glob is the default (to remain non-breaking) and would become node in a future major ?

[webpro]

Just saying, the generic (and intended) solution to this is to add entry patterns to your knip config manually:

{
  "entry": ["./src/public/{a,b}/index.ts"]
}

At this point this feels better than rewriting * to globstar ** and marking "everything" as an entry file (the node option), even though it goes 100% against the "zero-config aim".

[maastrich]

I'll have to try it, but I think that next major i there is one should handle exports as specified in node.js docs

[webpro]

Understood, but this is a good example of static analysis versus runtime behavior and there are tradeoffs to be considered.