Clean up code/tests

app/assets/javascripts/timeoutPopup.js

@@ -1,7 +1,12 @@
+window.GOVUK = window.GOVUK || {};
+window.GOVUK.Modules = window.GOVUK.Modules || {};
+window.GOVUK.Modules.TimeoutPopup = window.GOVUK.Modules.TimeoutPopup || {};
+
 (function(global) {
     "use strict";
 
     const sessionTimer = document.getElementById("sessionTimer");
+    let intervalId = null;
 
     function checkTimer(timeTillSessionEnd) {
         var now = new Date().getTime();
@@ -13,7 +18,8 @@
         document.getElementById("logOutTimer").addEventListener("click", logoutUser);
         document.getElementById("extendSessionTimer").addEventListener("click", extendSession);
         if (difference < 0) {
-            clearInterval(x);
+            clearInterval(intervalId);
+            intervalId = null;
             closeTimer();
             logoutUser();
         }
@@ -35,12 +41,14 @@
         sessionTimer.close();
     }
 
-    global.GOVUK.Modules.TimeoutPopup = function() {
-        setTimeout(function() {
-            var timeTillSessionEnd = new Date().getTime() + (5 * 60 * 1000);
-            var x = setInterval(checkTimer, 1000, timeTillSessionEnd);
-        }, 25 * 60 * 1000);
-    };
+    function setSessionTimer() {
+        var timeTillSessionEnd = new Date().getTime() + (5 * 60 * 1000);
+        intervalId = setInterval(checkTimer, 1000, timeTillSessionEnd);
+    }
+
+    if (document.getElementById("timeLeft") !== null) {
+        setTimeout(setSessionTimer, 60 * 1000);
+    }
 
     global.GOVUK.Modules.TimeoutPopup.checkTimer = checkTimer;
     global.GOVUK.Modules.TimeoutPopup.logoutUser = logoutUser;

tests/javascripts/timeoutPopup.test.js

@@ -1,5 +1,4 @@
 beforeAll(() => {
-    jest.useFakeTimers();
     jest.spyOn(global, 'setTimeout');
 
     document.body.innerHTML = `
@@ -40,13 +39,24 @@ beforeAll(() => {
 });
 
 afterAll(() => {
-    jest.useRealTimers();
     document.body.innerHTML = '';
 });
 
 
-describe('When an authenticated user', () => {
-    test('does whatever', () => {
+describe('When the session timer module is loaded', () => {
+    beforeEach(() => {
+        jest.useFakeTimers();
+    });
+
+    afterEach(() => {
+        jest.useFakeTimers();
+    });
+
+    test('everything initializes properly', () => {
+        const sessionTimer = document.getElementById("sessionTimer");
+        sessionTimer.showModal = jest.fn();
+        sessionTimer.close = jest.fn();
+
         jest.runAllTimers();
     });
 
@@ -54,6 +64,14 @@ describe('When an authenticated user', () => {
 
 
 describe('The session timer ', () => {
+    beforeEach(() => {
+        jest.useFakeTimers();
+    });
+
+    afterEach(() => {
+        jest.useFakeTimers();
+    });
+
     test('logoutUser method logs the user out', () => {
         const logoutUserMethod = window.GOVUK.Modules.TimeoutPopup.logoutUser;