vscode-extension-samples/vim-sample/.vscode/launch.json

// A launch configuration that compiles the extension and then opens it inside a new window
{
	"version": "0.2.0",
	"configurations": [
		{
			"name": "Run Extension",
			"type": "extensionHost",
			"request": "launch",
			"runtimeExecutable": "${execPath}",
			"args": ["--extensionDevelopmentPath=${workspaceRoot}"],
			"outFiles": ["${workspaceFolder}/out/**/*.js"],
			"preLaunchTask": "npm: watch"
		}
	]
}