Resolve WES-113 "Commons tests"

Assets/Common/PlayModeTests/BackButtonTests.cs

@@ -0,0 +1,44 @@
+using System.Collections;
+using System.Linq;
+using System.IO;
+
+using NUnit.Framework;
+using TMPro;
+using UnityEngine;
+using UnityEngine.TestTools;
+using UnityEngine.SceneManagement;
+
+
+public class BackButtonTests
+{
+
+    [UnitySetUp]
+    public IEnumerator SetupFunction()
+    {
+        string path = Path.Combine("Assets", "users.json");
+        var oneUser = "{\"currentUserIndex\": 0,\"storedUsers\": [{\"username\": \"TEST\",\"avatar\": {\"instanceID\": 40848},\"playtime\": 0.0,\"courses\": [],\"minigames\": []}]}";
+
+        using (StreamWriter writer = new StreamWriter(path))
+        {
+            writer.Write(oneUser);
+        }
+        
+        SystemController.GetInstance().LoadNextScene("Common/Scenes/MainMenuScreen");
+        yield return new WaitForSeconds(0.2f);
+        SystemController.GetInstance().LoadNextScene("Common/Scenes/ListMinigamesScreen");
+        yield return new WaitForSeconds(0.2f);
+    }
+
+    [UnityTest]
+    public IEnumerator BackTest()
+    {
+
+        var backButton = (BackButton) GameObject.FindObjectOfType(typeof(BackButton));
+        backButton.Back();
+        yield return new WaitForSeconds(0.2f);
+
+        var mainMenuScreen = (MainMenuScreen) GameObject.FindObjectOfType(typeof(MainMenuScreen));
+        Assert.IsNotNull(mainMenuScreen);
+    }
+}
+