feat: pass new parameters directly to rendered component

fix test name

Author: egil

CHANGELOG.md

@@ -71,7 +71,6 @@ public void Add(IEnumerable<ComponentParameter> parameters)
 	/// the parameters in the collection passed to it.
 	/// </summary>
 	/// <typeparam name="TComponent">Type of component to render.</typeparam>
-	[SuppressMessage("Design", "MA0051:Method is too long", Justification = "TODO: Refactor")]
 	public RenderFragment ToRenderFragment<TComponent>()
 		where TComponent : IComponent
 	{

src/bunit.core/ComponentParameterCollection.cs

@@ -1,3 +1,4 @@
+using Bunit.Rendering;
 using System.Runtime.ExceptionServices;
 
 namespace Bunit;
@@ -28,24 +29,8 @@ public static void SetParametersAndRender<TComponent>(this IRenderedComponentBas
 		if (renderedComponent is null)
 			throw new ArgumentNullException(nameof(renderedComponent));
 
-		var result = renderedComponent.InvokeAsync(() =>
-			renderedComponent.Instance.SetParametersAsync(parameters));
-
-		if (result.IsFaulted && result.Exception is not null)
-		{
-			if (result.Exception.InnerExceptions.Count == 1)
-			{
-				ExceptionDispatchInfo.Capture(result.Exception.InnerExceptions[0]).Throw();
-			}
-			else
-			{
-				ExceptionDispatchInfo.Capture(result.Exception).Throw();
-			}
-		}
-		else if (!result.IsCompleted)
-		{
-			result.GetAwaiter().GetResult();
-		}
+		var renderer = renderedComponent.Services.GetRequiredService<TestRenderer>();
+		renderer.SetDirectParameters(renderedComponent, parameters);
 	}
 
 	/// <summary>

src/bunit.core/Extensions/RenderedComponentRenderExtensions.cs

@@ -52,7 +52,7 @@ Task DispatchEventAsync(
 	/// <summary>
 	/// Renders a <typeparamref name="TComponent"/> with the <paramref name="parameters"/> passed to it.
 	/// </summary>
-	/// <typeparam name = "TComponent" > The type of component to render.</typeparam>
+	/// <typeparam name="TComponent">The type of component to render.</typeparam>
 	/// <param name="parameters">The parameters to pass to the component.</param>
 	/// <returns>A <see cref="IRenderedComponentBase{TComponent}"/> that provides access to the rendered component.</returns>
 	IRenderedComponentBase<TComponent> RenderComponent<TComponent>(ComponentParameterCollection parameters)
@@ -77,5 +77,5 @@ IReadOnlyList<IRenderedComponentBase<TComponent>> FindComponents<TComponent>(IRe
 	/// <summary>
 	/// Disposes all components rendered by the <see cref="ITestRenderer" />.
 	/// </summary>
-	public void DisposeComponents();
+	void DisposeComponents();
 }

src/bunit.core/Rendering/ITestRenderer.cs

@@ -1,3 +1,4 @@
+using System.Reflection;
 using System.Runtime.ExceptionServices;
 using Microsoft.Extensions.Logging;
 
@@ -6,8 +7,13 @@ namespace Bunit.Rendering;
 /// <summary>
 /// Represents a bUnit <see cref="ITestRenderer"/> used to render Blazor components and fragments during bUnit tests.
 /// </summary>
+[SuppressMessage("Major Code Smell", "S3011:Reflection should not be used to increase accessibility of classes, methods, or fields", Justification = "Blazors internal API has been stable for a while now.")]
 public class TestRenderer : Renderer, ITestRenderer
 {
+	private static readonly Type RendererType = typeof(Renderer);
+	private static readonly FieldInfo IsBatchInProgressField = RendererType.GetField("_isBatchInProgress", BindingFlags.Instance | BindingFlags.NonPublic)!;
+	private static readonly MethodInfo GetRequiredComponentStateMethod = RendererType.GetMethod("GetRequiredComponentState", BindingFlags.Instance | BindingFlags.NonPublic)!;
+
 	private readonly object renderTreeUpdateLock = new();
 	private readonly SynchronizationContext? usersSyncContext = SynchronizationContext.Current;
 	private readonly Dictionary<int, IRenderedFragmentBase> renderedComponents = new();
@@ -18,6 +24,14 @@ public class TestRenderer : Renderer, ITestRenderer
 	private TaskCompletionSource<Exception> unhandledExceptionTsc = new(TaskCreationOptions.RunContinuationsAsynchronously);
 	private Exception? capturedUnhandledException;
 
+	private bool IsBatchInProgress
+	{
+#pragma warning disable S1144 // Unused private types or members should be removed
+		get => (bool)(IsBatchInProgressField.GetValue(this) ?? false);
+#pragma warning restore S1144 // Unused private types or members should be removed
+		set => IsBatchInProgressField.SetValue(this, value);
+	}
+
 	/// <inheritdoc/>
 	public Task<Exception> UnhandledException => unhandledExceptionTsc.Task;
 
@@ -164,6 +178,34 @@ public void DisposeComponents()
 		AssertNoUnhandledExceptions();
 	}
 
+	/// <inheritdoc/>
+	internal void SetDirectParameters(IRenderedFragmentBase renderedComponent, ParameterView parameters)
+	{
+		Dispatcher.InvokeAsync(() =>
+		{
+			try
+			{
+				IsBatchInProgress = true;
+
+				var componentState = GetRequiredComponentStateMethod.Invoke(this, new object[] { renderedComponent.ComponentId })!;
+				var setDirectParametersMethod = componentState.GetType().GetMethod("SetDirectParameters", BindingFlags.Public | BindingFlags.Instance)!;
+				setDirectParametersMethod.Invoke(componentState, new object[] { parameters });
+			}
+			catch (TargetInvocationException ex) when (ex.InnerException is not null)
+			{
+				HandleException(ex.InnerException);
+			}
+			finally
+			{
+				IsBatchInProgress = false;
+			}
+
+			ProcessPendingRender();
+		});
+
+		AssertNoUnhandledExceptions();
+	}
+
 	/// <inheritdoc/>
 	protected override void ProcessPendingRender()
 	{
@@ -375,7 +417,7 @@ void FindComponentsInRenderTree(int componentId)
 		}
 	}
 
-	IRenderedComponentBase<TComponent> GetOrCreateRenderedComponent<TComponent>(RenderTreeFrameDictionary framesCollection, int componentId, TComponent component)
+	private IRenderedComponentBase<TComponent> GetOrCreateRenderedComponent<TComponent>(RenderTreeFrameDictionary framesCollection, int componentId, TComponent component)
 		where TComponent : IComponent
 	{
 		if (renderedComponents.TryGetValue(componentId, out var renderedComponent))

src/bunit.core/Rendering/TestRenderer.cs

@@ -48,6 +48,7 @@ public static IServiceCollection AddDefaultTestContextServices(this IServiceColl
 		// bUnit specific services
 		services.AddSingleton<TestContextBase>(testContext);
 		services.AddSingleton<WebTestRenderer>();
+		services.AddSingleton<TestRenderer>(s => s.GetRequiredService<WebTestRenderer>());
 		services.AddSingleton<Renderer>(s => s.GetRequiredService<WebTestRenderer>());
 		services.AddSingleton<ITestRenderer>(s => s.GetRequiredService<WebTestRenderer>());
 		services.AddSingleton<HtmlComparer>();

src/bunit.web/Extensions/TestServiceProviderExtensions.cs

@@ -423,6 +423,38 @@ public void Test203()
 		Renderer.UnhandledException.Result.ShouldBeOfType<InvalidOperationException>();
 	}
 
+	[Fact(DisplayName = "Multiple calls to StateHasChanged from OnParametersSet with SetParametersAndRender")]
+	public void Test204()
+	{
+		var cut = RenderComponent<MultipleStateHasChangedInOnParametersSet>();
+		cut.RenderCount.ShouldBe(1);
+
+		cut.SetParametersAndRender();
+		cut.RenderCount.ShouldBe(2);
+	}
+
+	[Fact(DisplayName = "Multiple calls to StateHasChanged from OnParametersSet with Render")]
+	public void Test205()
+	{
+		var cut = RenderComponent<MultipleStateHasChangedInOnParametersSet>();
+		cut.RenderCount.ShouldBe(1);
+
+		cut.Render();
+		cut.RenderCount.ShouldBe(2);
+	}
+
+	[Fact(DisplayName = "Multiple calls to StateHasChanged from OnParametersSet with event dispatch render trigger")]
+	public void Test206()
+	{
+		var cut = RenderComponent<TriggerChildContentRerenderViaClick>();
+		var child = cut.FindComponent<MultipleStateHasChangedInOnParametersSet>();
+		child.RenderCount.ShouldBe(1);
+
+		cut.Find("button").Click();
+
+		child.RenderCount.ShouldBe(2);
+	}
+
 	internal sealed class NoChildNoParams : ComponentBase
 	{
 		public const string MARKUP = "hello world";

tests/bunit.core.tests/Rendering/TestRendererTest.cs

@@ -0,0 +1,16 @@
+namespace Bunit.TestAssets.SampleComponents;
+
+public class MultipleStateHasChangedInOnParametersSet : ComponentBase
+{
+	[Parameter]
+	public int Value { get; set; }
+
+	protected override void OnParametersSet()
+	{
+		base.OnParametersSet();
+		StateHasChanged();
+		StateHasChanged();
+		StateHasChanged();
+	}
+}
+

tests/bunit.testassets/SampleComponents/MultipleStateHasChangedInOnParametersSet.cs

@@ -0,0 +1,6 @@
+@* TriggerChildContentRerenderViaClick.razor *@
+<button @onclick="() => counter++">Count = @counter</button>
+<MultipleStateHasChangedInOnParametersSet Value="counter" />
+@code {
+    int counter;
+}