Today I learnt new about debugging mocha tests.

The following is how I debugged using Microsoft’s awesome VSCode editor

In the root of your project, create a folder with the following name .vscode
Within that folder, create a file named launch.json

Open your launch.json and add the following configuration:

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{
	"version": "0.1.0",
	"configurations": [
		{
			"name": "Debug Mocha Test",
			"type": "node",
			"address": "localhost",
			"port": 5858,
			"sourceMaps": false
		}
	]
}

From your projects root, run your test runner with the debug argument like

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mocha test --debug-brk

Or if you’ve created a debug script in your package.json like

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"scripts": {
	"debug": "mocha --debug-brk"
}

then run it like

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npm run debug

In your vscode editor, switch over to the debug panel on the left-hand side and start the debugger.
Adding breakpoints in the test code will cause the runner to pause giving you all the time you need to debug you tests!!