fix: allow using 3rd party IComponentActivator at the same time as component factories

Author: egil

CHANGELOG.md

@@ -8,6 +8,8 @@ All notable changes to **bUnit** will be documented in this file. The project ad
 
 ### Fixed
 
+- Allow using 3rd party `IComponentActivator` at the same time as component factories. By [@egil](https://github.com/egil). Reported by [BenSchoen](https://github.com/BenSchoen) in https://github.com/bUnit-dev/bUnit/issues/1129.
+
 - Calling `IRenderedComponent.Render()` or `IRenderedComponent.SetParametersAndRender()` did not batch up multiple synchronous re-renders after setting parameters. This is now changed such that the method causes the component to re-render with new parameters in the same way as if a parent component had passed new parameters to it. By [@egil](https://github.com/egil). Reported by [@Jcparkyn](https://github.com/Jcparkyn) in https://github.com/bUnit-dev/bUnit/issues/1119.
 
 ## [1.20.8] - 2023-05-21

src/bunit.core/ComponentFactoryCollection.cs

@@ -1,6 +1,5 @@
 #if NET5_0_OR_GREATER
 using System.Collections;
-using System.Collections.Generic;
 
 namespace Bunit;
 

src/bunit.core/Rendering/BunitComponentActivator.cs

@@ -1,17 +1,16 @@
 #if NET5_0_OR_GREATER
-using System;
-using System.Diagnostics.CodeAnalysis;
-using Microsoft.AspNetCore.Components;
 
 namespace Bunit.Rendering;
 
 internal class BunitComponentActivator : IComponentActivator
 {
 	private readonly ComponentFactoryCollection factories;
+	private readonly IComponentActivator componentActivator;
 
-	public BunitComponentActivator(ComponentFactoryCollection factories)
+	public BunitComponentActivator(ComponentFactoryCollection factories, IComponentActivator? externalComponentActivator)
 	{
 		this.factories = factories ?? throw new ArgumentNullException(nameof(factories));
+		this.componentActivator = externalComponentActivator ?? DefaultComponentActivator.Instance;
 	}
 
 	public IComponent CreateInstance([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)] Type componentType)
@@ -39,7 +38,18 @@ public IComponent CreateInstance([DynamicallyAccessedMembers(DynamicallyAccessed
 			}
 		}
 
-		return (IComponent)Activator.CreateInstance(componentType)!;
+		return componentActivator.CreateInstance(componentType);
+	}
+
+	private sealed class DefaultComponentActivator : IComponentActivator
+	{
+		public static IComponentActivator Instance { get; } = new DefaultComponentActivator();
+
+		/// <inheritdoc />
+		public IComponent CreateInstance([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)] Type componentType)
+		{			
+			return (IComponent)Activator.CreateInstance(componentType)!;
+		}
 	}
 }
 #endif

src/bunit.core/Rendering/TestRenderer.cs

@@ -43,6 +43,7 @@ private bool IsBatchInProgress
 	/// </summary>
 	internal int RenderCount { get; private set; }
 
+#if NETSTANDARD
 	/// <summary>
 	/// Initializes a new instance of the <see cref="TestRenderer"/> class.
 	/// </summary>
@@ -52,13 +53,22 @@ public TestRenderer(IRenderedComponentActivator renderedComponentActivator, Test
 		logger = loggerFactory.CreateLogger<TestRenderer>();
 		this.activator = renderedComponentActivator;
 	}
+#elif NET5_0_OR_GREATER
+	/// <summary>
+	/// Initializes a new instance of the <see cref="TestRenderer"/> class.
+	/// </summary>
+	public TestRenderer(IRenderedComponentActivator renderedComponentActivator, TestServiceProvider services, ILoggerFactory loggerFactory)
+		: base(services, loggerFactory, new BunitComponentActivator(services.GetRequiredService<ComponentFactoryCollection>(), null))
+	{
+		logger = loggerFactory.CreateLogger<TestRenderer>();
+		this.activator = renderedComponentActivator;
+	}
 
-#if NET5_0_OR_GREATER
 	/// <summary>
 	/// Initializes a new instance of the <see cref="TestRenderer"/> class.
 	/// </summary>
 	public TestRenderer(IRenderedComponentActivator renderedComponentActivator, TestServiceProvider services, ILoggerFactory loggerFactory, IComponentActivator componentActivator)
-		: base(services, loggerFactory, componentActivator)
+		: base(services, loggerFactory, new BunitComponentActivator(services.GetRequiredService<ComponentFactoryCollection>(), componentActivator))
 	{
 		logger = loggerFactory.CreateLogger<TestRenderer>();
 		this.activator = renderedComponentActivator;

src/bunit.core/TestContextBase.cs

@@ -54,7 +54,7 @@ protected TestContextBase()
 	{
 		Services = new TestServiceProvider();
 #if NET5_0_OR_GREATER
-		Services.AddSingleton<IComponentActivator>(new BunitComponentActivator(ComponentFactories));
+		Services.AddSingleton<ComponentFactoryCollection>(_ => ComponentFactories);
 #endif
 	}
 

tests/bunit.core.tests/Rendering/BunitComponentActivatorTest.cs

@@ -0,0 +1,61 @@
+#if NET5_0_OR_GREATER
+
+using Bunit.TestDoubles;
+
+namespace Bunit.Rendering;
+
+public class BunitComponentActivatorTest : TestContext
+{
+	[Fact(DisplayName = "Default activator")]
+	public void Test001()
+	{
+		var activator = new CustomComponentActivator();
+		Services.AddSingleton<IComponentActivator>(activator);
+
+		var cut = RenderComponent<Simple1>();
+
+		cut.Instance.ShouldBeOfType<Simple1>();
+	}
+
+	[Fact(DisplayName = "Custom singleton IComponentActivator registered in Services")]
+	public void Test002()
+	{
+		var activator = new CustomComponentActivator();
+		Services.AddSingleton<IComponentActivator>(activator);
+
+		RenderComponent<Simple1>();
+
+		activator.RequestedComponentTypes
+			.ShouldHaveSingleItem()
+			.ShouldBe(typeof(Simple1));
+	}
+
+	[Fact(DisplayName = "Custom singleton IComponentActivator registered in Services with ComponentFactories in use")]
+	public void Test003()
+	{
+		var activator = new CustomComponentActivator();
+		Services.AddSingleton<IComponentActivator>(activator);
+		ComponentFactories.AddStub<ClickCounter>();
+
+		var cut = RenderComponent<Wrapper>(ps => ps.AddChildContent<ClickCounter>());
+
+		activator.RequestedComponentTypes
+			.ShouldHaveSingleItem()
+			.ShouldBe(typeof(Wrapper));
+		cut.HasComponent<ClickCounter>().ShouldBeFalse();
+		cut.HasComponent<Stub<ClickCounter>>().ShouldBeTrue();
+	}
+
+	private sealed class CustomComponentActivator : IComponentActivator
+	{
+		public List<Type> RequestedComponentTypes { get; } = new();
+
+		public IComponent CreateInstance(Type componentType)
+		{
+			RequestedComponentTypes.Add(componentType);
+			return (IComponent)Activator.CreateInstance(componentType)!;
+		}
+	}
+}
+
+#endif