Merge pull request #2376 from StephenHodgson/MRTK-vNEXT-Checks

Added asserts for things

Author: David Kline

Assets/MixedRealityToolkit/InputSystem/Focus/FocusProvider.cs

@@ -228,6 +228,9 @@ private void Awake()
 
         private void Start()
         {
+            Debug.Assert(MixedRealityManager.IsInitialized, "No Mixed Reality Manager found in the scene.  Be sure to run the Mixed Reality Configuration.");
+            Debug.Assert(InputSystem != null, "No Input System found, Did you set it up in your configuration profile?");
+
             // Register the FocusProvider as a global listener to get input events.
             InputSystem.Register(gameObject);
         }

Assets/MixedRealityToolkit/InputSystem/Gaze/GazeProvider.cs

@@ -208,6 +208,9 @@ protected virtual void OnEnable()
 
         private void Start()
         {
+            Debug.Assert(MixedRealityManager.IsInitialized, "No Mixed Reality Manager found in the scene.  Be sure to run the Mixed Reality Configuration.");
+            Debug.Assert(InputSystem != null, "No Input System found, Did you set it up in your configuration profile?");
+
             if (cursorPrefab != null)
             {
                 var cursorObj = Instantiate(cursorPrefab, transform);

Assets/MixedRealityToolkit/_Core/Utilities/CameraCache.cs

@@ -16,24 +16,15 @@ public static class CameraCache
         /// <summary>
         /// Returns a cached reference to the main camera and uses Camera.main if it hasn't been cached yet.
         /// </summary>
-        public static Camera Main
-        {
-            get
-            {
-                if (cachedCamera == null)
-                {
-                    return Refresh(Camera.main);
-                }
-                return cachedCamera;
-            }
-        }
+        public static Camera Main => cachedCamera == null ? Refresh(Camera.main) : cachedCamera;
 
         /// <summary>
         /// Set the cached camera to a new reference and return it
         /// </summary>
         /// <param name="newMain">New main camera to cache</param>
         public static Camera Refresh(Camera newMain)
         {
+            Debug.Assert(newMain != null, "No camera with MainCamera tag found in scene.  Did you forget to tag your camera?");
             return cachedCamera = newMain;
         }
     }