Doesn't Appear to work with Top level node Exports

[dairyisscary]

Hello!

Thanks for the great package! However, I ran into an issue with packages that use a exports for the "top-level" node modules export. This package only appears to work if the import request is for a submodule like import x from "my-node-package/submodule";. it is possible for a package to use the exports field for root like import x from "my-node-package";.

For an example of this, see solid js which uses exports quite extensively to support different code paths in the server vs the browser.

https://github.com/solidjs/solid/blob/main/packages/solid/package.json#L37

In other words, jest-node-exports-resolver seems to work correctly when importing solid-js/web but not solid-js. i was able to work around this by making two changes to the resolver:

    if (!request.startsWith("@")) {
      if (length > 1) {
        packageName = pkgPathParts[0];
        submoduleName = `./${pkgPathParts.slice(1).join("/")}`;
      } else { // <- added this else
        packageName = request;
        submoduleName = ".";
      }
    } else if (length > 2) {
      packageName = pkgPathParts.slice(0, 2).join("/");
      submoduleName = `./${pkgPathParts.slice(2).join("/")}`; // <- I'm not sure if this line works for @namepspace/root packages but i didn't have any packages lie that to test
    } 

i also needed to add a check on conditions since this change alone broke for the package expect (which has a conditions of undefined) as far as i can tell, this is a good change regardless since we can skip the resolveExport function in more cases

        if (typeof exportValue === "string")
          targetFilePath = exportKey.endsWith("*")
            ? exportValue.replace(/\*/, submoduleName.slice(exportKey.length - 1))
            : exportValue;
        else if (conditions && exportValue !== null && typeof exportValue === "object") { // <- Modified this line
          function resolveExport(exportValue, prevKeys) {

I have no idea if these changes are good in general. i'd be happy to make a PR if you think this is good idea.

[piranna]

For an example of this, see solid js which uses exports quite extensively to support different code paths in the server vs the browser.

solidjs/solid@main/packages/solid/package.json#L37

That package.json file is using node condition, that's not supported by jest. That's the reason why it's not working for you. In fact, I have another PR open to add support to it. It's not a problem of jest-node-exports-resolver.

[dairyisscary]

oh right! i failed to mention, i actually desire the browser conditions (since i want to test a "browser" like/client env). I've already made my own test environment with browser. even with this env, though, jest-node-exports-resolver still doesn't resolve the "." exports.

To be clear, i have something like this:

const JsdomEnv = require("jest-environment-jsdom");

module.exports = class MyEnv extends JsdomEnv {
  exportConditions() {
    return ["browser"];
  }
};

and I'm using this env in jest's testEnviornment configuration.

console logging in jest-node-exports-resolver produces correct ["browser"] as conditions value for the solid-js request.

[piranna]

Do you have a test case that we can replicate?

[dairyisscary]

@piranna good idea. i should have just done this from the get go.

https://github.com/dairyisscary/jest-enviorn-root

$ node --version 
v16.13.0
$ npm install
$ npm test

if the test fails, that means that jest is using the server version of solid-js (./dist/server.js), when i want the browser version(./dist/solid.js). the test it will pass if it imports the correct version -- i verified that by monkey patching my local installation of jest-node-exports-resolver. hope this helps.

[piranna]

I've published a new version 1.1.5, can you check if it works?

[dairyisscary]

@piranna its working swimmingly! thank you so much for your efforts. I consider this issue closed.

(side note, i was able to pull your 1.1.5 from npm but it looks like you've forgotten to push your changes to github too -- just a heads up)