This repository exposes an issue with using vscode-js-debug in the cases where program is a wrapper used to determine an actual file.

For purposes of the example, the compiled files and sourcemaps are available in ./dist

Setup

npm install

The Problem

Given the configuration

{
  "type": "node",
  "request": "launch",
  "name": "Debug Current Test File",
  "program": "${workspaceFolder}/bin/mocha-current-file",
  "args": [
    "${file}"
  ],
  "outFiles": [
    "${workspaceFolder}/dist"
  ],
  "sourceMaps": true,
}

The file ./bin/mocha-current-file.js does the following:

consumes the ${file} argument, which is the currently focused file in the vscode editor. In this example, it is src/index.unit.ts
determines the name and location of the compiled typescript file, in this case, dist/index.unit.js
Shows an (unfollowed) example of a setup where there might be complicated "before all test" setup, e.g. for cleanly creating and tearing down databases.
invokes mocha through require('mocha/lib/cli').main(['dist/index.unit.js])

You can substitute your favorite test framework, this also happens with Jest and AVA.

Examples

Given these breakpoints:

When not using the preview.

// settings.json
{
    "debug.javascript.usePreview": false,    
}

Note how we are currently stopped on the breakpoint in the source file.

When using the preview

// settings.json
{
    "debug.javascript.usePreview": false,    
}

Note how we are currently stopped on the debugger; line in the compiled distfile ./dist/index.unit.js

Traces

Traces are committed to ./tracefile.json

mschnee / debug-breakpoint-example