Using a requires shim (tsx, esbuild-register, @swc-node/register) causes breakpoint sourcemaps to not work

[JustinGrote]

.vscode-test.js

module.exports = {
  files: '**/*.test.ts',
  cachePath: `${__dirname}/../../.vscode-test`,
  mocha: {
    ui: 'bdd',
    preload: 'esbuild-register'
  },
};

Using "sourcemapped" example and debug mode in the test runner.

Tests run fine and the transpiler requires shim works fine for mocha to transpile the ts file in-place, but when the breakpoint hits, it does not recognize the sourcemap and go to the original file:

This works just fine when using mocha on the command line regularly.

This is potentially a js-debug extension issue or some odd combination about running mocha inside the vscode electron compiled app, but I wanted to start the conversation here because I didn't observe this behavior when I wrote my own custom mocha test runner for Pester.

Workaround

Toggle over to the original file to make edits rather than being able to edit-in-place, so this is mostly just an efficiency annoyance.