This is a basic repository reproducing an issue related to missing externs for :target :npm-module and exploring possible solutions.
> npm i
> npm run devThis installs the local dependency random-module and then runs the dev server, which watches the src directory and compiles the app.main namespace for both :target :browser and :target :npm-module.
As described in app.main when using an anonymous function, the :target :browser build can successfully figure out the type of the binding for the result of calling a JavaScript function while :target :npm-module cannot. While this is expected (:target :npm-module doesn't so any analysis of JS code), a manual type hint on the binding doesn't help either, and the only way to fix the warning is to add the type hint to the anonymous function argument %. Since externs inferrencing is disabled this seems to point to an issue with the way :target :npm-module is compiled.
Is there a way to get around adding ^js to the anonymous function argument? I tried to add a manual externs.js file but couldn't get it to work as well.