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

// A launch configuration that compiles the extension and then opens it inside a new window
{
	"version": "0.1.0",
	"configurations": [
		{
			"name": "Launch Extension",
			"type": "extensionHost",
			"request": "launch",
			"runtimeExecutable": "${execPath}",
			"args": ["--extensionDevelopmentPath=${workspaceRoot}" ],
			"stopOnEntry": false,
			"sourceMaps": true,
			"outFiles": ["${workspaceRoot}/out/src/**/*.js"],
			"preLaunchTask": "npm"
		},
		{
			"name": "Launch Tests",
			"type": "extensionHost",
			"request": "launch",
			"runtimeExecutable": "${execPath}",
			"args": ["--extensionDevelopmentPath=${workspaceRoot}", "--extensionTestsPath=${workspaceRoot}/out/test" ],
			"stopOnEntry": false,
			"sourceMaps": true,
			"outFiles": ["${workspaceRoot}/out/test/**/*.js"],
			"preLaunchTask": "npm"
		}
	]
}