Task.Delay(10) removed from mock services, renderers and View models that could cause potential deadlocks and synchronisation issues, in favour of Task.CompletedTask and Task.FromResult.

src/Mobile/eShopOnContainers/eShopOnContainers.Core/Services/Basket/BasketMockService.cs

@@ -18,52 +18,48 @@ namespace eShopOnContainers.Core.Services.Basket
                 }
         };
 
-        public async Task<CustomerBasket> GetBasketAsync(string guidUser, string token)
+        public Task<CustomerBasket> GetBasketAsync(string guidUser, string token)
         {
-            await Task.Delay(10);
-
             if (string.IsNullOrEmpty(guidUser) || string.IsNullOrEmpty(token))
             {
-                return new CustomerBasket();
+                return Task.FromResult(new CustomerBasket());
             }
 
-            return MockCustomBasket;
+            return Task.FromResult(MockCustomBasket);
         }
 
-        public async Task<CustomerBasket> UpdateBasketAsync(CustomerBasket customerBasket, string token)
+        public Task<CustomerBasket> UpdateBasketAsync(CustomerBasket customerBasket, string token)
         {
-            await Task.Delay(10);
-
             if (string.IsNullOrEmpty(token))
             {
-                return new CustomerBasket();
+                return Task.FromResult(new CustomerBasket());
             }
 
             MockCustomBasket = customerBasket;
 
-            return MockCustomBasket;
+            return Task.FromResult(MockCustomBasket);
         }
 
-        public async Task ClearBasketAsync(string guidUser, string token)
+        public Task ClearBasketAsync(string guidUser, string token)
         {
-            await Task.Delay(10);
-
             if (string.IsNullOrEmpty(token))
             {
-                return;
+                return Task.CompletedTask;
             }
 
             if (!string.IsNullOrEmpty(guidUser))
             {
                 MockCustomBasket.Items.Clear();
             }
+
+            return Task.CompletedTask;
         }
 
         public Task CheckoutAsync(BasketCheckout basketCheckout, string token)
         {
             if (string.IsNullOrEmpty(token))
             {
-                return Task.FromResult(0);
+                return Task.CompletedTask;
             }
 
             if (basketCheckout != null)
@@ -71,7 +67,7 @@ namespace eShopOnContainers.Core.Services.Basket
                 MockCustomBasket.Items.Clear();
             }
 
-            return Task.FromResult(0);
+            return Task.CompletedTask;
         }
     }
 }

src/Mobile/eShopOnContainers/eShopOnContainers.Core/Services/Catalog/CatalogMockService.cs

@@ -31,35 +31,27 @@ namespace eShopOnContainers.Core.Services.Catalog
             new CatalogItem { Id = Common.Common.MockCatalogItemId05, PictureUri = Device.RuntimePlatform != Device.UWP ? "fake_product_05.png" : "Assets/fake_product_05.png", Name = "Azure Black Sweatshirt (M)", Price = 19.50M, CatalogBrandId = 1, CatalogBrand = "Azure", CatalogTypeId = 2, CatalogType = "T-Shirt" }
         };
 
-        public async Task<ObservableCollection<CatalogItem>> GetCatalogAsync()
+        public Task<ObservableCollection<CatalogItem>> GetCatalogAsync()
         {
-            await Task.Delay(10);
-
-            return MockCatalog;
+            return Task.FromResult(MockCatalog);
         }
 
-        public async Task<ObservableCollection<CatalogItem>> FilterAsync(int catalogBrandId, int catalogTypeId)
+        public Task<ObservableCollection<CatalogItem>> FilterAsync(int catalogBrandId, int catalogTypeId)
         {
-            await Task.Delay(10);
-
-            return MockCatalog
+            return Task.FromResult(MockCatalog
                 .Where(c => c.CatalogBrandId == catalogBrandId &&
                 c.CatalogTypeId == catalogTypeId)
-                .ToObservableCollection();
+                .ToObservableCollection());
         }
 
-        public async Task<ObservableCollection<CatalogBrand>> GetCatalogBrandAsync()
+        public Task<ObservableCollection<CatalogBrand>> GetCatalogBrandAsync()
         {
-            await Task.Delay(10);
-
-            return MockCatalogBrand;
+            return Task.FromResult(MockCatalogBrand);
         }
 
-        public async Task<ObservableCollection<CatalogType>> GetCatalogTypeAsync()
-        {
-            await Task.Delay(10);
-
-            return MockCatalogType;
+        public Task<ObservableCollection<CatalogType>> GetCatalogTypeAsync()
+        { 
+            return Task.FromResult(MockCatalogType);
         }
     }
 }

src/Mobile/eShopOnContainers/eShopOnContainers.Core/Services/Marketing/CampaignMockService.cs

@@ -36,16 +36,14 @@ namespace eShopOnContainers.Core.Services.Marketing
             }
         };
 
-        public async Task<ObservableCollection<CampaignItem>> GetAllCampaignsAsync(string token)
+        public Task<ObservableCollection<CampaignItem>> GetAllCampaignsAsync(string token)
         {
-            await Task.Delay(10);
-            return _mockCampaign;
+            return Task.FromResult(_mockCampaign);
         }
 
-        public async Task<CampaignItem> GetCampaignByIdAsync(int campaignId, string token)
+        public Task<CampaignItem> GetCampaignByIdAsync(int campaignId, string token)
         {
-            await Task.Delay(10);
-            return _mockCampaign.SingleOrDefault(c => c.Id == campaignId);
+            return Task.FromResult(_mockCampaign.SingleOrDefault(c => c.Id == campaignId));
         }
     }
 }

src/Mobile/eShopOnContainers/eShopOnContainers.Core/Services/Order/OrderMockService.cs

@@ -72,39 +72,35 @@ namespace eShopOnContainers.Core.Services.Order
             Street = "FakeStreet"
         };
 
-        public async Task<ObservableCollection<Models.Orders.Order>> GetOrdersAsync(string token)
+        public Task<ObservableCollection<Models.Orders.Order>> GetOrdersAsync(string token)
         {
-            await Task.Delay(10);
-
             if (!string.IsNullOrEmpty(token))
             {
-                return MockOrders
+                return Task.FromResult(MockOrders
                     .OrderByDescending(o => o.OrderNumber)
-                    .ToObservableCollection();
+                    .ToObservableCollection());
             }
             else
-                return new ObservableCollection<Models.Orders.Order>();
+                return Task.FromResult(new ObservableCollection<Models.Orders.Order>());
         }
 
-        public async Task<Models.Orders.Order> GetOrderAsync(int orderId, string token)
+        public Task<Models.Orders.Order> GetOrderAsync(int orderId, string token)
         {
-            await Task.Delay(10);
-
             if (!string.IsNullOrEmpty(token))
-                return MockOrders
-                    .FirstOrDefault(o => o.OrderNumber.Equals(orderId));
+                return Task.FromResult(MockOrders
+                    .FirstOrDefault(o => o.OrderNumber.Equals(orderId)));
             else
-                return new Models.Orders.Order();
+                return Task.FromResult(new Models.Orders.Order());
         }
 
-        public async Task CreateOrderAsync(Models.Orders.Order newOrder, string token)
+        public Task CreateOrderAsync(Models.Orders.Order newOrder, string token)
         {
-            await Task.Delay(10);
-
             if (!string.IsNullOrEmpty(token))
             {
                 MockOrders.Add(newOrder);
             }
+
+            return Task.CompletedTask;
         }
 
         public BasketCheckout MapOrderToBasket(Models.Orders.Order order)

src/Mobile/eShopOnContainers/eShopOnContainers.Core/Services/User/UserMockService.cs

@@ -26,10 +26,9 @@ namespace eShopOnContainers.Core.Services.User
             CardSecurityNumber = "1234"
         };
 
-        public async Task<UserInfo> GetUserInfoAsync(string authToken)
+        public Task<UserInfo> GetUserInfoAsync(string authToken)
         {
-            await Task.Delay(10);
-            return MockUserInfo;
+            return Task.FromResult(MockUserInfo);
         }
     }
 }

src/Mobile/eShopOnContainers/eShopOnContainers.Core/ViewModels/LoginViewModel.cs

@@ -160,8 +160,6 @@ namespace eShopOnContainers.Core.ViewModels
             {
                 try
                 {
-                    await Task.Delay(10);
-
                     isAuthenticated = true;
                 }
                 catch (Exception ex)
@@ -185,17 +183,17 @@ namespace eShopOnContainers.Core.ViewModels
             IsBusy = false;
         }
 
-        private async Task SignInAsync()
+        private Task SignInAsync()
         {
             IsBusy = true;
 
-            await Task.Delay(10);
-
             LoginUrl = _identityService.CreateAuthorizationRequest();
 
             IsValid = true;
             IsLogin = true;
             IsBusy = false;
+
+            return Task.CompletedTask;
         }
 
         private void Register()

src/Mobile/eShopOnContainers/eShopOnContainers.Droid/Renderers/CustomTabbedPageRenderer.cs

@@ -19,7 +19,6 @@ namespace eShopOnContainers.Droid.Renderers
 {
     public class CustomTabbedPageRenderer : TabbedPageRenderer
     {
-        private const int DelayBeforeTabAdded = 10;
         protected readonly Dictionary<Element, BadgeView> BadgeViews = new Dictionary<Element, BadgeView>();
         private TabLayout _tabLayout;
         private LinearLayout _tabStrip;
@@ -186,10 +185,8 @@ namespace eShopOnContainers.Droid.Renderers
             BadgeViews.Remove(e.Element);
         }
 
-        private async void OnTabAdded(object sender, ElementEventArgs e)
+        private void OnTabAdded(object sender, ElementEventArgs e)
         {
-            await Task.Delay(DelayBeforeTabAdded);
-
             var page = e.Element as Page;
 
             if (page == null)

src/Mobile/eShopOnContainers/eShopOnContainers.UnitTests/Mocks/MockSettingsService.cs

@@ -86,7 +86,7 @@ namespace eShopOnContainers.UnitTests.Mocks
             }
 
             _settings[key] = value;
-            return Task.Delay(10);
+            return Task.FromResult(false);
         }
 
         T GetValueOrDefaultInternal<T>(string key, T defaultValue = default(T))

src/Mobile/eShopOnContainers/eShopOnContainers.Windows/Services/LocationServiceImplementation.cs

@@ -64,7 +64,6 @@ namespace eShopOnContainers.Windows.Services
                 var status = _locator.LocationStatus;
                 while (status == PositionStatus.Initializing)
                 {
-                    Task.Delay(10).Wait();
                     status = _locator.LocationStatus;
                 }
                 return status != PositionStatus.NotAvailable;
@@ -78,7 +77,6 @@ namespace eShopOnContainers.Windows.Services
                 var status = _locator.LocationStatus;
                 while (status == PositionStatus.Initializing)
                 {
-                    Task.Delay(10).Wait();
                     status = _locator.LocationStatus;
                 }
                 return status != PositionStatus.Disabled && status != PositionStatus.NotAvailable;

src/Mobile/eShopOnContainers/eShopOnContainers.iOS/Renderers/CustomTabbedPageRenderer.cs

@@ -74,10 +74,8 @@ namespace eShopOnContainers.iOS.Renderers
             }
         }
 
-        private async void OnTabAdded(object sender, ElementEventArgs e)
+        private void OnTabAdded(object sender, ElementEventArgs e)
         {
-            await Task.Delay(10);
-
             var page = e.Element as Page;
             if (page == null)
                 return;