To debug a test file in VSCode, create the following launch configuration.

  // For more information, visit:
  "version": "0.2.0",
  "configurations": [
      "type": "pwa-node",
      "request": "launch",
      "name": "Debug Current Test File",
      "autoAttachChildProcesses": true,
      "skipFiles": ["<node_internals>/**", "**/node_modules/**"],
      "program": "${workspaceRoot}/node_modules/vitest/vitest.mjs",
      "args": ["run", "${relativeFile}"],
      "smartStep": true,
      "console": "integratedTerminal"

Then in the debug tab ensure 'Debug Current Test File' is selected, you can then open the test file you want to debug and press F5 to start debugging.

IntelliJ IDEA

Create a 'Node.js' run configuration. Use the following settings to run all tests in debug mode:

Working directory/path/to/your-project-root
JavaScript file./node_modules/vitest/vitest.mjs
Application parametersrun --threads false

Then run this configuration in debug mode. The IDE will stop at JS/TS breakpoints set in the editor.