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Webpack 5 Node Interface - can't resolve loader from node_modules

See original GitHub issue

Bug report

What is the current behavior?

I’m trying to compile custom TypeScript code in Node at runtime using Webpack 5.

It says it can’t resolve ts-loader from node_modules because node_modules doesn’t exist, except it definitely does exist.

Here’s the error from the log:

[   {
    loc: 'main',
    message: "Module not found: Error: Can't resolve 'ts-loader' in 'D:\\Projects\\projectCode\\projectcode-server-test'",
    details: "resolve 'ts-loader' in 'D:\\Projects\\projectCode\\projectcode-server-test'\n" +
      '  Parsed request is a module\n' +
      '  No description file found in D:\\Projects\\projectCode\\projectcode-server-test or above\n' +
      '  resolve as module\n' +
      "    D:\\Projects\\projectCode\\projectcode-server-test\\node_modules doesn't exist or is not a directory\n" +
      "    D:\\Projects\\projectCode\\node_modules doesn't exist or is not a directory\n" +
      "    D:\\Projects\\node_modules doesn't exist or is not a directory\n" +
      "    D:\\node_modules doesn't exist or is not a directory",
    stack: "ModuleNotFoundError: Module not found: Error: Can't resolve 'ts-loader' in 'D:\\Projects\\projectCode\\projectcode-server-test'\n" +
      '    at D:\\Projects\\projectCode\\projectcode-server-test\\node_modules\\webpack\\lib\\Compilation.js:1762:28\n'
+
      '    at D:\\Projects\\projectCode\\projectcode-server-test\\node_modules\\webpack\\lib\\NormalModuleFactory.js:730:13\n'
+
      '    at eval (eval at create (D:\\Projects\\projectCode\\projectcode-server-test\\node_modules\\tapable\\lib\\HookCodeFactory.js:33:10), <anonymous>:8:1)\n' +
      '    at D:\\Projects\\projectCode\\projectcode-server-test\\node_modules\\webpack\\lib\\NormalModuleFactory.js:273:22\n'
+
      '    at eval (eval at create (D:\\Projects\\projectCode\\projectcode-server-test\\node_modules\\tapable\\lib\\HookCodeFactory.js:33:10), <anonymous>:7:1)\n' +
      '    at D:\\Projects\\projectCode\\projectcode-server-test\\node_modules\\webpack\\lib\\NormalModuleFactory.js:488:15\n'
+
      '    at D:\\Projects\\projectCode\\projectcode-server-test\\node_modules\\webpack\\lib\\NormalModuleFactory.js:117:11\n'
+
      '    at D:\\Projects\\projectCode\\projectcode-server-test\\node_modules\\webpack\\lib\\NormalModuleFactory.js:571:8\n'
+
      '    at D:\\Projects\\projectCode\\projectcode-server-test\\node_modules\\neo-async\\async.js:2830:7\n'
+
      '    at done (D:\\Projects\\projectCode\\projectcode-server-test\\node_modules\\neo-async\\async.js:2925:13)' } ]

If the current behavior is a bug, please provide the steps to reproduce.

Create a new project with the following files and run it:

index.js

const webpack = require('webpack');
const { createFsFromVolume, Volume } = require('memfs');

const vol = Volume.fromJSON({
    './src/index.tsx': `
        console.log('index test');
    `
});

const inputFS = createFsFromVolume(vol);
const outputFS = createFsFromVolume( new Volume() );

const compiler = webpack(
    {
        entry: './src/index.tsx',
        mode: 'production',
        module: {
            rules: [
                {
                    test: /\.tsx?$/,
                    use: 'ts-loader'
                }
            ]
        },
        resolve: {
          extensions: ['.tsx', '.ts', '.jsx', '.js'],
        },
        output: {
            filename: 'bundle.js'
        }
    }
);

compiler.inputFileSystem = inputFS;
compiler.outputFileSystem = outputFS;

compiler.run((err, stats) => {
    if (err) {
        console.error(err.stack || err);

        if (err.details) console.error(err.details);

        return;
    }

    const info = stats.toJson();

    if (stats.hasErrors()) console.error(info.errors);

    if (stats.hasWarnings()) console.warn(info.warnings);
});

package.json

{
  "name": "projectcode-server-test",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "start": "node index.js"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "memfs": "^3.2.2",
    "ts-loader": "^9.2.2",
    "webpack": "^5.37.1"
  }
}

What is the expected behavior?

node_modules should be found since it exists in the expected path, and ts-loader should be resolved.

Other relevant information: webpack version: 5.37.1 Node.js version: 12.16.2 Operating System: Windows 10 Pro Additional tools: None