Clarify handling of URL assets / Using child process with Typescript

[Robstei]

My goal is to eventually use child processes in nextjs.

But i realised that i can't get basic url parsing for ts files to work.

How can i create a second bundle based on new URL call with a path to a ts file?

It is my understanding that the test.ts is loaded as asset but also beeing parsed.

repo for the code

//main.ts

const url: URL = new URL("./test.ts", import.meta.url);
console.log(url);

//test.ts

export const echo = (message: string) => {
  return message;
};

//webpack.config.cjs

const path = require("path");

module.exports = {
  entry: "./src/main.ts",
  mode: "production",
  target: "node",
  module: {
    rules: [
      {
        test: /\.tsx?$/,
        use: "ts-loader",
        exclude: /node_modules/,
      },
    ],
  },
  output: {
    filename: "bundle.js",
    path: path.resolve(__dirname, "dist"),
  },
};

Here are specific questions about things i don't understand:

1. Why ist test.ts parsed and not just copy & pasted? The docs only mention that the files are "emitted to the output directory"
2. Why does type: "javascript/auto prevent this? According to docs this prevents the default rules for matching files.
   My problem is that this loader is apparently not used for test.ts without this line. I think that because the file is emmitted as a ts file (if ts loader would came to use it should be a js file right?).
3. Is that the correct way to prevent webpack from emmiting somewhat parsed ts files from URL assets or is there a better way?
4. what happens when multiple rules match a file? Is this correct? (issue)

When multiple rules match a module in webpack, all matching rules are applied in the order they are defined in the configuration. This means the first matching rule is applied first, followed by the second, and so on.

5. Why does a second rule like this not work?

 {
test: /\.ts?$/,
use: "ts-loader",
dependency: "url",}

To me this says. "use the ts-loader for all ts files that are come from new URL calls"

Instead i get the following error:

ERROR in /home/user/repos/webpack_url_parsing_not_working/src/test.ts(1,22)
TS7006: Parameter 'message' implicitly has an 'any' type.

I then tried to create two bundles with two entries. This seems to work. But...
6. Is there a way to reference the input file and not the output file?

const url = path.join(import.meta.url, "../../dist/test.bundle.cjs");

7. Is there a way to do it with new URL? Webpack checks if the file acutally exists and it doesn't exist when i run the webpack command.
8. Is this the recommended way to use child processes with webpack?

[alexander-akait]

Can you create a full reproducible test repo what you try and describable why you need to use new URL(), do you want to just process ts to js and load it as a asset file (no bundling in such case)