[tests] dont show alert if in test

frappe/core/doctype/test_runner/test_runner.js

@@ -23,6 +23,7 @@ frappe.ui.form.on('Test Runner', {
 
 	},
 	run_tests: function(frm, files) {
+		frappe.flags.in_test = true;
 		let require_list = [
 			"assets/frappe/js/lib/jquery/qunit.js",
 			"assets/frappe/js/lib/jquery/qunit.css"

frappe/public/js/frappe/desk.js

@@ -483,6 +483,7 @@ frappe.Application = Class.extend({
 
 	setup_beforeunload: function() {
 		window.onbeforeunload = function () {
+			if (frappe.flags.in_test) return false;
 			var unsaved_docs = [];
 			for (doctype in locals) {
 				for (name in locals[doctype]) {