Namespace created from exports reporting that the exports are unused when using namespace imports

[shawnmcknight]

I've created a reproduction at https://github.com/shawnmcknight/knip-import-exported-ns.

The scenario I am seeing is that when a namespace is imported via import * as ns and that namespace is created via re-exporting other modules then there is a false positive on those re-exported modules being unused exports.

In my example reproduction, there are three subfolders as follows:

• ns-not-reexported: This folder contains an index.ts file which directly exports two named exports - apple and orange.
• ns-named-reexported: This folder contains files named apricot.ts and peach.ts which individually export named apricot and peach. These are then re-exported as named exports in the folder's index.ts.
• ns-default-reexported: This folder contains files named blueberry.ts and pear.ts which export default blueberry and pear respectively. These default exports and then re-exported as named exports in the folder's index.ts.

In the root folder, there is an index.ts which imports each of these three subfolders using import * as ns syntax and then simply does a console.log of each of those. Based upon my understanding of the namespace import heuristic, this should result in no unused exports during knip's validation.

The namespace in the ns-not-reexported folder is not reported as an unused export. However, the namespaces in the ns-default-reexported and ns-named-reexported folders are reported as unused exports. It seems that the re-exporting process is causing those to be missed.

Here is the knip output from my reproduction:

Unused exports (4)
default  unknown  ns-default-reexported/blueberry.ts:2:8
default  unknown  ns-default-reexported/pear.ts:2:8
apricot  unknown  ns-named-reexported/apricot.ts:1:14
peach    unknown  ns-named-reexported/peach.ts:1:14

The apple and orange exports are properly identified as being used, but the other four are being flagged as unused.

Please let me know if there is anything else I can provide to assist!

[shawnmcknight]

This is possibly related to #626, but I'm not totally sure.

[webpro]

Thanks for reproduction, looks clear. There's quite a few cases covered in re-exports-* fixture folders, but apparently this one is missing indeed. To be continued.

[webpro]

🚀 This issue has been resolved in v5.22.3. See Release 5.22.3 for release notes.

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[webpro]

Thanks again @shawnmcknight, did a refactor and it should behave better now!

[shawnmcknight]

I just tested in my repo and it's working as expected now. Thank you!