Added ability to render a fragment to test context, and pass it as the expected value to markup matches methods

Author: egil

src/bunit.core/RazorTesting/FragmentContainer.cs

@@ -9,7 +9,7 @@ namespace Bunit.RazorTesting
 	/// when a fragment is rendered inside a test contexts render tree.
 	/// It is primarily used to be able to find the starting point to return.
 	/// </summary>
-	internal sealed class FragmentContainer : ComponentBase
+	public sealed class FragmentContainer : ComponentBase
 	{
 		/// <summary>
 		/// The content to wrap.
@@ -25,7 +25,7 @@ protected override void BuildRenderTree(RenderTreeBuilder builder)
 		/// <summary>
 		/// Wraps the <paramref name="wrappingTarget"/> in a <see cref="FragmentContainer"/>.
 		/// </summary>
-		internal static RenderFragment Wrap(RenderFragment wrappingTarget)
+		public static RenderFragment Wrap(RenderFragment wrappingTarget)
 		{
 			return builder =>
 			{

src/bunit.core/TestContextBase.cs

@@ -1,7 +1,5 @@
 using System;
-using Bunit.RazorTesting;
 using Bunit.Rendering;
-using Microsoft.AspNetCore.Components;
 using Microsoft.Extensions.DependencyInjection;
 
 namespace Bunit
@@ -53,46 +51,6 @@ protected TestContextBase()
 			Services = new TestServiceProvider();			
 		}
 
-		/// <summary>
-		/// Renders a component, declared in the <paramref name="renderFragment"/>, inside the <see cref="RenderTree"/>.
-		/// </summary>
-		/// <typeparam name="TComponent">The type of component to render.</typeparam>
-		/// <param name="renderFragment">The <see cref="RenderFragmentBase"/> that contains a declaration of the component.</param>
-		/// <returns>A <see cref="IRenderedComponentBase{TComponent}"/>.</returns>
-		protected IRenderedComponentBase<TComponent> RenderComponentBase<TComponent>(RenderFragment renderFragment) where TComponent : IComponent
-		{
-			// Wrap TComponent in any layout components added to the test context.
-			// If one of the layout components is the same type as TComponent,
-			// make sure to return the rendered component, not the layout component.			
-			var resultBase = Renderer.RenderFragment(RenderTree.Wrap(renderFragment));
-
-			// This ensures that the correct component is returned, in case an added layout component
-			// is of type TComponent.
-			var renderTreeTComponentCount = RenderTree.GetCountOf<TComponent>();
-			var result = renderTreeTComponentCount > 0
-				? Renderer.FindComponents<TComponent>(resultBase)[renderTreeTComponentCount]
-				: Renderer.FindComponent<TComponent>(resultBase);
-
-			return result;
-		}
-
-		/// <summary>
-		/// Renders a fragment, declared in the <paramref name="renderFragment"/>, inside the <see cref="RenderTree"/>.
-		/// </summary>
-		/// <param name="renderFragment">The <see cref="RenderFragmentBase"/> to render.</param>
-		/// <returns>A <see cref="IRenderedFragmentBase"/>.</returns>
-		protected IRenderedFragmentBase RenderFragmentBase(RenderFragment renderFragment)
-		{
-			// Wrap fragment in a FragmentContainer so the start of the test supplied
-			// razor fragment can be found after, and then wrap in any layout components
-			// added to the test context.		
-			var wrappedInFragmentContainer = FragmentContainer.Wrap(renderFragment);
-			var wrappedInRenderTree = RenderTree.Wrap(wrappedInFragmentContainer);
-			var resultBase = Renderer.RenderFragment(wrappedInRenderTree);
-
-			return Renderer.FindComponent<FragmentContainer>(resultBase);
-		}
-
 		/// <inheritdoc/>
 		public void Dispose()
 		{

src/bunit.web/Asserting/MarkupMatchesAssertExtensions.cs

@@ -3,6 +3,7 @@
 using Bunit.Asserting;
 using Bunit.Diffing;
 using Bunit.Rendering;
+using Microsoft.AspNetCore.Components;
 using Microsoft.Extensions.DependencyInjection;
 
 namespace Bunit
@@ -23,6 +24,11 @@ public static class MarkupMatchesAssertExtensions
 		[AssertionMethod]
 		public static void MarkupMatches(this string actual, string expected, string? userMessage = null)
 		{
+			if (actual is null)
+				throw new ArgumentNullException(nameof(actual));
+			if (expected is null)
+				throw new ArgumentNullException(nameof(expected));
+
 			using var parser = new BunitHtmlParser();
 			var actualNodes = parser.Parse(actual);
 			var expectedNodes = parser.Parse(expected);
@@ -31,15 +37,17 @@ public static void MarkupMatches(this string actual, string expected, string? us
 
 		/// <summary>
 		/// Verifies that the rendered markup from the <paramref name="actual"/> markup fragment matches
-		/// the <paramref name="expected"/> <see cref="IRenderedFragmentBase"/>, using the <see cref="HtmlComparer"/> type.
+		/// the <paramref name="expected"/> <see cref="IRenderedFragment"/>, using the <see cref="HtmlComparer"/> type.
 		/// </summary>
 		/// <exception cref="HtmlEqualException">Thrown when the <paramref name="actual"/> markup does not match the <paramref name="expected"/> markup.</exception>
 		/// <param name="actual">The markup fragment to verify.</param>
-		/// <param name="expected">The expected <see cref="IRenderedFragmentBase"/>.</param>
+		/// <param name="expected">The expected <see cref="IRenderedFragment"/>.</param>
 		/// <param name="userMessage">A custom user message to display in case the verification fails.</param>
 		[AssertionMethod]
 		public static void MarkupMatches(this string actual, IRenderedFragment expected, string? userMessage = null)
 		{
+			if (actual is null)
+				throw new ArgumentNullException(nameof(actual));
 			if (expected is null)
 				throw new ArgumentNullException(nameof(expected));
 
@@ -58,6 +66,8 @@ public static void MarkupMatches(this string actual, IRenderedFragment expected,
 		[AssertionMethod]
 		public static void MarkupMatches(this string actual, INodeList expected, string? userMessage = null)
 		{
+			if (actual is null)
+				throw new ArgumentNullException(nameof(actual));
 			if (expected is null)
 				throw new ArgumentNullException(nameof(expected));
 
@@ -76,6 +86,8 @@ public static void MarkupMatches(this string actual, INodeList expected, string?
 		[AssertionMethod]
 		public static void MarkupMatches(this string actual, INode expected, string? userMessage = null)
 		{
+			if (actual is null)
+				throw new ArgumentNullException(nameof(actual));
 			if (expected is null)
 				throw new ArgumentNullException(nameof(expected));
 
@@ -84,7 +96,7 @@ public static void MarkupMatches(this string actual, INode expected, string? use
 		}
 
 		/// <summary>
-		/// Verifies that the rendered markup from the <paramref name="actual"/> <see cref="IRenderedFragmentBase"/> matches
+		/// Verifies that the rendered markup from the <paramref name="actual"/> <see cref="IRenderedFragment"/> matches
 		/// the <paramref name="expected"/> markup, using the <see cref="HtmlComparer"/> type.
 		/// </summary>
 		/// <exception cref="HtmlEqualException">Thrown when the <paramref name="actual"/> markup does not match the <paramref name="expected"/> markup.</exception>
@@ -104,8 +116,8 @@ public static void MarkupMatches(this IRenderedFragment actual, string expected,
 		}
 
 		/// <summary>
-		/// Verifies that the rendered markup from the <paramref name="actual"/> <see cref="IRenderedFragmentBase"/> matches
-		/// the rendered markup from the <paramref name="expected"/> <see cref="IRenderedFragmentBase"/>, using the <see cref="HtmlComparer"/> type.
+		/// Verifies that the rendered markup from the <paramref name="actual"/> <see cref="IRenderedFragment"/> matches
+		/// the rendered markup from the <paramref name="expected"/> <see cref="IRenderedFragment"/>, using the <see cref="HtmlComparer"/> type.
 		/// </summary>
 		/// <exception cref="HtmlEqualException">Thrown when the <paramref name="actual"/> markup does not match the <paramref name="expected"/> markup.</exception>
 		/// <param name="actual">The rendered fragment to verify.</param>
@@ -124,7 +136,7 @@ public static void MarkupMatches(this IRenderedFragment actual, IRenderedFragmen
 
 		/// <summary>
 		/// Verifies that the <paramref name="actual"/> <see cref="INodeList"/> matches
-		/// the rendered markup from the <paramref name="expected"/> <see cref="IRenderedFragmentBase"/>, using the <see cref="HtmlComparer"/> 
+		/// the rendered markup from the <paramref name="expected"/> <see cref="IRenderedFragment"/>, using the <see cref="HtmlComparer"/> 
 		/// type.
 		/// </summary>
 		/// <exception cref="HtmlEqualException">Thrown when the <paramref name="actual"/> markup does not match the <paramref name="expected"/> markup.</exception>
@@ -144,7 +156,7 @@ public static void MarkupMatches(this INodeList actual, IRenderedFragment expect
 
 		/// <summary>
 		/// Verifies that the <paramref name="actual"/> <see cref="INode"/> matches
-		/// the rendered markup from the <paramref name="expected"/> <see cref="IRenderedFragmentBase"/>, using the <see cref="HtmlComparer"/> 
+		/// the rendered markup from the <paramref name="expected"/> <see cref="IRenderedFragment"/>, using the <see cref="HtmlComparer"/> 
 		/// type.
 		/// </summary>
 		/// <exception cref="HtmlEqualException">Thrown when the <paramref name="actual"/> markup does not match the <paramref name="expected"/> markup.</exception>
@@ -176,6 +188,8 @@ public static void MarkupMatches(this INode actual, string expected, string? use
 		{
 			if (actual is null)
 				throw new ArgumentNullException(nameof(actual));
+			if (expected is null)
+				throw new ArgumentNullException(nameof(expected));
 
 			var expectedNodes = expected.ToNodeList(actual.GetHtmlParser());
 			actual.MarkupMatches(expectedNodes, userMessage);
@@ -195,6 +209,8 @@ public static void MarkupMatches(this INodeList actual, string expected, string?
 		{
 			if (actual is null)
 				throw new ArgumentNullException(nameof(actual));
+			if (expected is null)
+				throw new ArgumentNullException(nameof(expected));
 
 			var expectedNodes = expected.ToNodeList(actual.GetHtmlParser());
 			actual.MarkupMatches(expectedNodes, userMessage);
@@ -212,6 +228,11 @@ public static void MarkupMatches(this INodeList actual, string expected, string?
 		[AssertionMethod]
 		public static void MarkupMatches(this INodeList actual, INodeList expected, string? userMessage = null)
 		{
+			if (actual is null)
+				throw new ArgumentNullException(nameof(actual));
+			if (expected is null)
+				throw new ArgumentNullException(nameof(expected));
+
 			var diffs = actual.CompareTo(expected);
 
 			if (diffs.Count != 0)
@@ -230,6 +251,11 @@ public static void MarkupMatches(this INodeList actual, INodeList expected, stri
 		[AssertionMethod]
 		public static void MarkupMatches(this INodeList actual, INode expected, string? userMessage = null)
 		{
+			if (actual is null)
+				throw new ArgumentNullException(nameof(actual));
+			if (expected is null)
+				throw new ArgumentNullException(nameof(expected));
+
 			var diffs = actual.CompareTo(expected);
 
 			if (diffs.Count != 0)
@@ -248,12 +274,80 @@ public static void MarkupMatches(this INodeList actual, INode expected, string?
 		[AssertionMethod]
 		public static void MarkupMatches(this INode actual, INodeList expected, string? userMessage = null)
 		{
+			if (actual is null)
+				throw new ArgumentNullException(nameof(actual));
+			if (expected is null)
+				throw new ArgumentNullException(nameof(expected));
+
 			var diffs = actual.CompareTo(expected);
 
 			if (diffs.Count != 0)
 				throw new HtmlEqualException(diffs, expected, actual, userMessage);
 		}
 
+		/// <summary>
+		/// Verifies that the rendered markup from the <paramref name="actual"/> <see cref="IRenderedFragment"/> matches
+		/// the rendered markup from the <paramref name="expected"/> <see cref="RenderFragment"/>, using the <see cref="HtmlComparer"/> type.
+		/// </summary>
+		/// <exception cref="HtmlEqualException">Thrown when the <paramref name="actual"/> markup does not match the <paramref name="expected"/> markup.</exception>
+		/// <param name="actual">The rendered fragment to verify.</param>
+		/// <param name="expected">The render fragment whose output to compare against.</param>
+		/// <param name="userMessage">A custom user message to display in case the verification fails.</param>
+		[AssertionMethod]
+		public static void MarkupMatches(this IRenderedFragment actual, RenderFragment expected, string? userMessage = null)
+		{
+			if (actual is null)
+				throw new ArgumentNullException(nameof(actual));
+			if (expected is null)
+				throw new ArgumentNullException(nameof(expected));
+
+			var testContext = actual.Services.GetRequiredService<TestContext>();
+			var renderedFragment = testContext.Render(expected);
+			MarkupMatches(actual, renderedFragment, userMessage);
+		}
+
+		/// <summary>
+		/// Verifies that the markup from the <paramref name="actual"/> matches
+		/// the rendered markup from the <paramref name="expected"/> <see cref="RenderFragment"/>, using the <see cref="HtmlComparer"/> type.
+		/// </summary>
+		/// <exception cref="HtmlEqualException">Thrown when the <paramref name="actual"/> markup does not match the <paramref name="expected"/> markup.</exception>
+		/// <param name="actual">The markup to verify.</param>
+		/// <param name="expected">The render fragment whose output to compare against.</param>
+		/// <param name="userMessage">A custom user message to display in case the verification fails.</param>
+		[AssertionMethod]
+		public static void MarkupMatches(this INode actual, RenderFragment expected, string? userMessage = null)
+		{
+			if (actual is null)
+				throw new ArgumentNullException(nameof(actual));
+			if (expected is null)
+				throw new ArgumentNullException(nameof(expected));
+
+			var testContext = actual.GetTestContext() ?? new TestContext();
+			var renderedFragment = testContext.Render(expected);
+			MarkupMatches(actual, renderedFragment, userMessage);
+		}
+
+		/// <summary>
+		/// Verifies that the markup from the <paramref name="actual"/> matches
+		/// the rendered markup from the <paramref name="expected"/> <see cref="RenderFragment"/>, using the <see cref="HtmlComparer"/> type.
+		/// </summary>
+		/// <exception cref="HtmlEqualException">Thrown when the <paramref name="actual"/> markup does not match the <paramref name="expected"/> markup.</exception>
+		/// <param name="actual">The markup to verify.</param>
+		/// <param name="expected">The render fragment whose output to compare against.</param>
+		/// <param name="userMessage">A custom user message to display in case the verification fails.</param>
+		[AssertionMethod]
+		public static void MarkupMatches(this INodeList actual, RenderFragment expected, string? userMessage = null)
+		{
+			if (actual is null)
+				throw new ArgumentNullException(nameof(actual));
+			if (expected is null)
+				throw new ArgumentNullException(nameof(expected));
+
+			var testContext = actual.GetTestContext() ?? new TestContext();
+			var renderedFragment = testContext.Render(expected);
+			MarkupMatches(actual, renderedFragment, userMessage);
+		}
+
 		private static INodeList ToNodeList(this string markup, BunitHtmlParser? htmlParser)
 		{
 			if (htmlParser is null)

src/bunit.web/Extensions/Internal/AngleSharpExtensions.cs

@@ -65,6 +65,28 @@ public static IEnumerable<INode> AsEnumerable(this INode node)
 			return nodes?.Length > 0 ? nodes[0].GetHtmlComparer() : null;
 		}
 
+		/// <summary>
+		/// Gets the <see cref="TestContext"/> stored in the <paramref name="node"/>s
+		/// owning context, if one is available. 
+		/// </summary>
+		/// <param name="node"></param>
+		/// <returns>The <see cref="TestContext"/> or null if not found.</returns>
+		public static TestContext? GetTestContext(this INode? node)
+		{
+			return node?.Owner.Context.GetService<TestContext>();
+		}
+
+		/// <summary>
+		/// Gets the <see cref="TestContext"/> stored in the <paramref name="nodes"/>s
+		/// owning context, if one is available. 
+		/// </summary>
+		/// <param name="nodes"></param>
+		/// <returns>The <see cref="TestContext"/> or null if not found.</returns>
+		public static TestContext? GetTestContext(this INodeList nodes)
+		{
+			return nodes?.Length > 0 ? nodes[0].GetTestContext() : null;
+		}
+
 		/// <summary>
 		/// Gets the parents of the <paramref name="element"/>, starting with
 		/// the <paramref name="element"/> itself.

src/bunit.web/Extensions/TestContextExtensions.cs

@@ -0,0 +1,51 @@
+using Bunit.RazorTesting;
+using Microsoft.AspNetCore.Components;
+
+namespace Bunit.Extensions
+{
+	internal static class TestContextExtensions
+	{
+		/// <summary>
+		/// Renders a component, declared in the <paramref name="renderFragment"/>, inside the <see cref="TestContextBase.RenderTree"/>.
+		/// </summary>
+		/// <typeparam name="TComponent">The type of component to render.</typeparam>
+		/// <param name="testContext">Test context to use to render with.</param>
+		/// <param name="renderFragment">The <see cref="RenderInsideRenderTree"/> that contains a declaration of the component.</param>
+		/// <returns>A <see cref="IRenderedComponentBase{TComponent}"/>.</returns>
+		public static IRenderedComponent<TComponent> RenderInsideRenderTree<TComponent>(this TestContextBase testContext, RenderFragment renderFragment) where TComponent : IComponent
+		{
+			// Wrap TComponent in any layout components added to the test context.
+			// If one of the layout components is the same type as TComponent,
+			// make sure to return the rendered component, not the layout component.			
+			var resultBase = testContext.Renderer.RenderFragment(testContext.RenderTree.Wrap(renderFragment));
+
+			// This ensures that the correct component is returned, in case an added layout component
+			// is of type TComponent.
+			var renderTreeTComponentCount = testContext.RenderTree.GetCountOf<TComponent>();
+			var result = renderTreeTComponentCount > 0
+				? testContext.Renderer.FindComponents<TComponent>(resultBase)[renderTreeTComponentCount]
+				: testContext.Renderer.FindComponent<TComponent>(resultBase);
+
+			return (IRenderedComponent<TComponent>)result;
+		}
+
+		/// <summary>
+		/// Renders a fragment, declared in the <paramref name="renderFragment"/>, inside the <see cref="TestContextBase.RenderTree"/>.
+		/// </summary>
+		/// <param name="testContext">Test context to use to render with.</param>
+		/// <param name="renderFragment">The <see cref="RenderInsideRenderTree"/> to render.</param>
+		/// <returns>A <see cref="IRenderedFragmentBase"/>.</returns>
+		public static IRenderedFragment RenderInsideRenderTree(this TestContextBase testContext, RenderFragment renderFragment)
+		{
+			// Wrap fragment in a FragmentContainer so the start of the test supplied
+			// razor fragment can be found after, and then wrap in any layout components
+			// added to the test context.		
+			var wrappedInFragmentContainer = FragmentContainer.Wrap(renderFragment);
+			var wrappedInRenderTree = testContext.RenderTree.Wrap(wrappedInFragmentContainer);
+			var resultBase = testContext.Renderer.RenderFragment(wrappedInRenderTree);
+
+			return (IRenderedFragment)testContext.Renderer.FindComponent<FragmentContainer>(resultBase);
+		}
+
+	}
+}

src/bunit.web/IRenderedFragment.cs

@@ -48,7 +48,5 @@ public interface IRenderedFragment : IRenderedFragmentBase
 		/// the snapshot and the rendered markup at that time.
 		/// </summary>
 		void SaveSnapshot();
-
-
 	}
 }

src/bunit.web/RazorTesting/Fixture.cs

@@ -142,12 +142,12 @@ private ComponentUnderTest SelectComponentUnderTest(string _)
 
 		private IRenderedComponent<TComponent> Factory<TComponent>(RenderFragment fragment) where TComponent : IComponent
 		{
-			return (IRenderedComponent<TComponent>)RenderComponentBase<TComponent>(fragment);
+			return this.RenderInsideRenderTree<TComponent>(fragment);
 		}
 
 		private IRenderedFragment Factory(RenderFragment fragment)
 		{
-			return (IRenderedFragment)RenderFragmentBase(fragment);
+			return this.RenderInsideRenderTree(fragment);
 		}
 
 		private static IRenderedComponent<TComponent> TryCastTo<TComponent>(IRenderedFragment target, [System.Runtime.CompilerServices.CallerMemberName] string sourceMethod = "") where TComponent : IComponent