Use CT instead of CTS in NavigationContext

Author: captainsafia

src/Components/Components/ref/Microsoft.AspNetCore.Components.netcoreapp.cs

@@ -559,7 +559,7 @@ public LocationChangedEventArgs(string location, bool isNavigationIntercepted) {
     public partial class NavigationContext
     {
         internal NavigationContext() { }
-        public System.Threading.CancellationTokenSource CancellationTokenSource { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } }
+        public System.Threading.CancellationToken CancellationToken { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } }
         public string Path { [System.Runtime.CompilerServices.CompilerGeneratedAttribute] get { throw null; } }
     }
     public partial class Router : Microsoft.AspNetCore.Components.IComponent, Microsoft.AspNetCore.Components.IHandleAfterRender, System.IDisposable

src/Components/Components/src/Routing/NavigationContext.cs

@@ -12,14 +12,14 @@ namespace Microsoft.AspNetCore.Components.Routing
 {
     public class NavigationContext
     {
-        internal NavigationContext(string path, CancellationTokenSource cancellationTokenSource)
+        internal NavigationContext(string path, CancellationToken cancellationToken)
         {
             Path = path;
-            CancellationTokenSource = cancellationTokenSource;
+            CancellationToken = cancellationToken;
         }
 
         public string Path { get; }
 
-        public CancellationTokenSource CancellationTokenSource { get; }
+        public CancellationToken CancellationToken { get; }
     }
 }

src/Components/Components/src/Routing/Router.cs

@@ -32,7 +32,7 @@ static readonly ReadOnlyDictionary<string, object> _emptyParametersDictionary
 
         private CancellationTokenSource _onNavigateCts;
 
-        private HashSet<Assembly> _assemblies = new HashSet<Assembly>();
+        private readonly HashSet<Assembly> _assemblies = new HashSet<Assembly>();
 
         [Inject] private NavigationManager NavigationManager { get; set; }
 
@@ -132,7 +132,7 @@ private void RefreshRouteTable()
             if (_assemblies.Count != assembliesSet.Count)
             {
                 Routes = RouteTableFactory.Create(assemblies);
-                _assemblies = assembliesSet;
+                _assemblies.UnionWith(assembliesSet);
             }
             // If the new assemblies set is the same length as the previous one,
             // we check if they are equal-by-value and refresh the route table if
@@ -143,7 +143,7 @@ private void RefreshRouteTable()
                 if (!_assemblies.SetEquals(assembliesSet))
                 {
                     Routes = RouteTableFactory.Create(assemblies);
-                    _assemblies = assembliesSet;
+                    _assemblies.UnionWith(assembliesSet);
                 }
             }
         }
@@ -210,14 +210,14 @@ private async Task RunOnNavigateAsync(string path, bool isNavigationIntercepted)
             // Create a new cancellation token source for this instance
             _onNavigateCts = new CancellationTokenSource();
 
-            var navigateContext = new NavigationContext(path, _onNavigateCts);
+            var navigateContext = new NavigationContext(path, _onNavigateCts.Token);
             var task = OnNavigateAsync(navigateContext);
 
             // Create a cancellation task based on the cancellation token
             // associated with the current running task.
             var cancellationTaskSource = new TaskCompletionSource();
-            navigateContext.CancellationTokenSource.Token.Register(() =>
-                cancellationTaskSource.TrySetCanceled(navigateContext.CancellationTokenSource.Token));
+            navigateContext.CancellationToken.Register(() =>
+                cancellationTaskSource.TrySetCanceled(navigateContext.CancellationToken));
 
             // If the user provided a Navigating render fragment, then show it.
             if (Navigating != null && task.Status != TaskStatus.RanToCompletion)

src/Components/test/testassets/BasicTestApp/RouterTest/TestRouterWithOnNavigate.razor

@@ -40,7 +40,7 @@
 
     public static async Task TestOnNavCancel(NavigationContext args)
     {
-        await Task.Delay(2000, args.CancellationTokenSource.Token);
+        await Task.Delay(2000, args.CancellationToken);
         Console.WriteLine("I'm not happening...");
     }
 }