Refactored bUnit JSInterop to make it more easily extendable

Author: egil

CHANGELOG.md

@@ -11,7 +11,9 @@ The following section list all changes in 1.0.0 preview 01.
 ### Added
 List of new features.
 
-- Added support for triggering `@ontoggle` event handlers through a dedicated `Toggle()` method. By [@egil](https://github.com/egil) in [#248](https://github.com/egil/bUnit/pull/248).
+- Added support for triggering `@ontoggle` event handlers through a dedicated `Toggle()` method. By [@egil](https://github.com/egil) in [#256](https://github.com/egil/bUnit/pull/256).
+
+- Added out of the box support for `<Virtualize>` component. When a `<Virtualize>` component is used in a component under test, it's JavaScript interop-calls are faked by bUnits JSInterop, and it should result in all items being rendered immediately.
 
 ### Changed
 List of changes in existing functionality.
@@ -24,6 +26,13 @@ List of changes in existing functionality.
 
   Learn more [issue #237](https://github.com/egil/bUnit/issues/237). By [@egil](https://github.com/egil) in [#247](https://github.com/egil/bUnit/pull/247).
 
+- The `Setup<TResult>(string identifier, Func<IReadOnlyList<object?>, bool> argumentsMatcher)` and `SetupVoid(string identifier, Func<IReadOnlyList<object?>, bool> argumentsMatcher)` methods in bUnits JSInterop/MockJSRuntime has a new second parameter, an `InvocationMatcher`.
+
+  The `InvocationMatcher` type is a delegate that receives a `JSRuntimeInvoation` and returns true. The `JSRuntimeInvoation` type contains the arguments of the invocation and the identifier for the invocation. This means old code using the `Setup` and `SetupVoid` methods should be updated to use the arguments list in `JSRuntimeInvoation`, e.g., change the following call:
+
+   `ctx.JSInterop.Setup<string>("foo", args => args.Count == 2)` to this:  
+   `ctx.JSInterop.Setup<string>("foo", invocation => invocation.Arguments.Count == 2)`.
+
 ### Removed
 List of now removed features.
 

src/bunit.core/Rendering/TestRenderer.cs

@@ -270,7 +270,15 @@ private void AssertNoUnhandledExceptions()
 			{
 				_unhandledException = null;
 				LogUnhandledException(unhandled);
-				ExceptionDispatchInfo.Capture(unhandled).Throw();
+
+				if (unhandled is AggregateException aggregateException && aggregateException.InnerExceptions.Count == 1)
+				{
+					ExceptionDispatchInfo.Capture(aggregateException.InnerExceptions[0]).Throw();
+				}
+				else
+				{
+					ExceptionDispatchInfo.Capture(unhandled).Throw();
+				}
 			}
 		}
 

src/bunit.web/JSInterop/BunitJSInterop.cs

@@ -52,26 +52,22 @@ public BunitJSInterop()
 		public JSRuntimeInvocationHandler<TResult> Setup<TResult>()
 		{
 			var result = new JSRuntimeInvocationHandler<TResult>(JSRuntimeInvocationHandler<object>.CatchAllIdentifier, _ => true);
-
-			AddHandler(result);
-
+			AddInvocationHandler(result);
 			return result;
 		}
 
 		/// <summary>
 		/// Configure a JSInterop invocation handler with the <paramref name="identifier"/> and arguments
-		/// passing the <paramref name="argumentsMatcher"/> test.
+		/// passing the <paramref name="invocationMatcher"/> test.
 		/// </summary>
 		/// <typeparam name="TResult">The result type of the invocation.</typeparam>
 		/// <param name="identifier">The identifier to setup a response for.</param>
-		/// <param name="argumentsMatcher">A matcher that is passed arguments received in invocations to <paramref name="identifier"/>. If it returns true the invocation is matched.</param>
+		/// <param name="invocationMatcher">A matcher that is passed an <see cref="JSRuntimeInvocation"/> associated with  the<paramref name="identifier"/>. If it returns true the invocation is matched.</param>
 		/// <returns>A <see cref="JSRuntimeInvocationHandler{TResult}"/>.</returns>
-		public JSRuntimeInvocationHandler<TResult> Setup<TResult>(string identifier, Func<IReadOnlyList<object?>, bool> argumentsMatcher)
+		public JSRuntimeInvocationHandler<TResult> Setup<TResult>(string identifier, InvocationMatcher invocationMatcher)
 		{
-			var result = new JSRuntimeInvocationHandler<TResult>(identifier, argumentsMatcher);
-
-			AddHandler(result);
-
+			var result = new JSRuntimeInvocationHandler<TResult>(identifier, invocationMatcher);
+			AddInvocationHandler(result);
 			return result;
 		}
 
@@ -84,22 +80,20 @@ public JSRuntimeInvocationHandler<TResult> Setup<TResult>(string identifier, Fun
 		/// <returns>A <see cref="JSRuntimeInvocationHandler{TResult}"/>.</returns>
 		public JSRuntimeInvocationHandler<TResult> Setup<TResult>(string identifier, params object[] arguments)
 		{
-			return Setup<TResult>(identifier, args => args.SequenceEqual(arguments));
+			return Setup<TResult>(identifier, invocation => invocation.Arguments.SequenceEqual(arguments));
 		}
 
 		/// <summary>
 		/// Configure a JSInterop invocation handler with the <paramref name="identifier"/> and arguments
-		/// passing the <paramref name="argumentsMatcher"/> test, that should not receive any result.
+		/// passing the <paramref name="invocationMatcher"/> test, that should not receive any result.
 		/// </summary>
 		/// <param name="identifier">The identifier to setup a response for.</param>
-		/// <param name="argumentsMatcher">A matcher that is passed arguments received in invocations to <paramref name="identifier"/>. If it returns true the invocation is matched.</param>
+		/// <param name="invocationMatcher">A matcher that is passed an <see cref="JSRuntimeInvocation"/> associated with  the<paramref name="identifier"/>. If it returns true the invocation is matched.</param>
 		/// <returns>A <see cref="JSRuntimeInvocationHandler"/>.</returns>
-		public JSRuntimeInvocationHandler SetupVoid(string identifier, Func<IReadOnlyList<object?>, bool> argumentsMatcher)
+		public JSRuntimeInvocationHandler SetupVoid(string identifier, InvocationMatcher invocationMatcher)
 		{
-			var result = new JSRuntimeInvocationHandler(identifier, argumentsMatcher);
-
-			AddHandler(result);
-
+			var result = new JSRuntimeInvocationHandler(identifier, invocationMatcher);
+			AddInvocationHandler(result);
 			return result;
 		}
 
@@ -112,7 +106,7 @@ public JSRuntimeInvocationHandler SetupVoid(string identifier, Func<IReadOnlyLis
 		/// <returns>A <see cref="JSRuntimeInvocationHandler"/>.</returns>
 		public JSRuntimeInvocationHandler SetupVoid(string identifier, params object[] arguments)
 		{
-			return SetupVoid(identifier, args => args.SequenceEqual(arguments));
+			return SetupVoid(identifier, invocation => invocation.Arguments.SequenceEqual(arguments));
 		}
 
 		/// <summary>
@@ -122,9 +116,7 @@ public JSRuntimeInvocationHandler SetupVoid(string identifier, params object[] a
 		public JSRuntimeInvocationHandler SetupVoid()
 		{
 			var result = new JSRuntimeInvocationHandler(JSRuntimeInvocationHandler<object>.CatchAllIdentifier, _ => true);
-
-			AddHandler(result);
-
+			AddInvocationHandler(result);
 			return result;
 		}
 
@@ -135,7 +127,7 @@ public JSRuntimeInvocationHandler SetupVoid()
 		/// </summary>
 		/// <returns>Returns the <see cref="JSRuntimeInvocationHandler{TResult}"/> or null if no one is found.</returns>
 		public JSRuntimeInvocationHandler<TResult>? TryGetInvokeHandler<TResult>(string identifier, object?[]? args = null)
-			=> TryGetHandlerFor<TResult>(new JSRuntimeInvocation(identifier, default, args));
+			=> TryGetHandlerFor<TResult>(new JSRuntimeInvocation(identifier, default, args)) as JSRuntimeInvocationHandler<TResult>;
 
 		/// <summary>
 		/// Looks through the registered handlers and returns the latest registered that can handle
@@ -145,7 +137,11 @@ public JSRuntimeInvocationHandler SetupVoid()
 		public JSRuntimeInvocationHandler? TryGetInvokeVoidHandler(string identifier, object?[]? args = null)
 			=> TryGetHandlerFor<object>(new JSRuntimeInvocation(identifier, default, args), x => x.IsVoidResultHandler) as JSRuntimeInvocationHandler;
 
-		private void AddHandler<TResult>(JSRuntimeInvocationHandler<TResult> handler)
+		/// <summary>
+		/// Adds an invocation handler to bUnit's JSInterop. Can be used to register
+		/// custom invocation handlers.
+		/// </summary>
+		public void AddInvocationHandler<TResult>(JSRuntimeInvocationHandlerBase<TResult> handler)
 		{
 			if (!_handlers.ContainsKey(handler.Identifier))
 			{
@@ -163,20 +159,23 @@ private void RegisterInvocation(JSRuntimeInvocation invocation)
 			_invocations[invocation.Identifier].Add(invocation);
 		}
 
-		private JSRuntimeInvocationHandler<TResult>? TryGetHandlerFor<TResult>(JSRuntimeInvocation invocation, Predicate<JSRuntimeInvocationHandler<TResult>>? handlerPredicate = null)
+		private JSRuntimeInvocationHandlerBase<TResult>? TryGetHandlerFor<TResult>(JSRuntimeInvocation invocation, Predicate<JSRuntimeInvocationHandlerBase<TResult>>? handlerPredicate = null)
 		{
 			handlerPredicate ??= _ => true;
-			JSRuntimeInvocationHandler<TResult>? result = default;
+			JSRuntimeInvocationHandlerBase<TResult>? result = default;
+
 			if (_handlers.TryGetValue(invocation.Identifier, out var plannedInvocations))
 			{
-				result = plannedInvocations.OfType<JSRuntimeInvocationHandler<TResult>>()
-					.Where(x => handlerPredicate(x) && x.Matches(invocation)).LastOrDefault();
+				result = plannedInvocations.OfType<JSRuntimeInvocationHandlerBase<TResult>>()
+					.LastOrDefault(x => handlerPredicate(x) && x.Matches(invocation));
 			}
 
-			if (result is null && _handlers.TryGetValue(JSRuntimeInvocationHandler<TResult>.CatchAllIdentifier, out var catchAllHandlers))
+			if (result is null && _handlers.TryGetValue(JSRuntimeInvocationHandler.CatchAllIdentifier, out var catchAllHandlers))
 			{
-				result = catchAllHandlers.OfType<JSRuntimeInvocationHandler<TResult>>().Where(x => handlerPredicate(x)).LastOrDefault();
+				result = catchAllHandlers.OfType<JSRuntimeInvocationHandlerBase<TResult>>()
+					.LastOrDefault(x => handlerPredicate(x) && x.Matches(invocation));
 			}
+
 			return result;
 		}
 
@@ -204,7 +203,7 @@ public ValueTask<TValue> InvokeAsync<TValue>(string identifier, CancellationToke
 			{
 				ValueTask<TValue>? result = default;
 
-				if (_jsInterop.TryGetHandlerFor<TValue>(invocation) is JSRuntimeInvocationHandler<TValue> handler)
+				if (_jsInterop.TryGetHandlerFor<TValue>(invocation) is JSRuntimeInvocationHandlerBase<TValue> handler)
 				{
 					var task = handler.RegisterInvocation(invocation);
 					result = new ValueTask<TValue>(task);

src/bunit.web/JSInterop/ComponentSupport/BunitJSInteropExtensions.cs

@@ -0,0 +1,20 @@
+namespace Bunit.JSInterop.ComponentSupport
+{
+	/// <summary>
+	/// Helper methods for registering handlers on the <see cref="BunitJSInterop"/>.
+	/// </summary>
+	public static class BunitJSInteropExtensions
+	{
+		/// <summary>
+		/// Adds the built-in JSRuntime invocation handlers to the <paramref name="jSInterop"/>.
+		/// </summary>
+		public static BunitJSInterop AddBuiltInJSRuntimeInvocationHandlers(this BunitJSInterop jSInterop)
+		{
+#if NET5_0
+			//jSInterop.AddInvocationHandler(new Virtualize.VirtualizeJSRuntimeInvocationHandler());
+#endif
+			return jSInterop;
+		}
+
+	}
+}

src/bunit.web/JSInterop/InvocationMatcher.cs

@@ -0,0 +1,11 @@
+namespace Bunit
+{
+	/// <summary>
+	/// Represents a invocation matcher / predicate, that is used to determine
+	/// if a <see cref="JSRuntimeInvocationHandlerBase{TResult}"/> matches a specific
+	/// <see cref="JSRuntimeInvocation"/>.
+	/// </summary>
+	/// <param name="invocation">The invocation to match against.</param>
+	/// <returns>True if the <see cref="JSRuntimeInvocationHandlerBase{TResult}"/> can handle the invocation, false otherwise.</returns>
+	public delegate bool InvocationMatcher(JSRuntimeInvocation invocation);
+}

src/bunit.web/JSInterop/JSRuntimeInvocationHandler.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Threading.Tasks;
 
 namespace Bunit
 {
@@ -9,110 +8,36 @@ namespace Bunit
 	/// and returns <typeparamref name="TResult"/>.
 	/// </summary>
 	/// <typeparam name="TResult">The expect result type.</typeparam>
-	public class JSRuntimeInvocationHandler<TResult>
+	public class JSRuntimeInvocationHandler<TResult> : JSRuntimeInvocationHandlerBase<TResult>
 	{
-		private readonly Func<IReadOnlyList<object?>, bool> _invocationMatcher;
-		internal const string CatchAllIdentifier = "*";
-
-		private readonly List<JSRuntimeInvocation> _invocations;
-
-		private TaskCompletionSource<TResult> _completionSource;
-
-		/// <summary>
-		/// Gets whether this handler is set up to handle calls to <c>InvokeVoidAsync=(string, object[])</c>.
-		/// </summary>
-		public virtual bool IsVoidResultHandler { get; } = false;
-
-		/// <summary>
-		/// Gets whether this handler will match any invocations that expect a <typeparamref name="TResult"/> as the return type.
-		/// </summary>
-		public bool IsCatchAllHandler { get; }
-
-		/// <summary>
-		/// The expected identifier for the function to invoke.
-		/// </summary>
-		public string Identifier { get; }
-
-		/// <summary>
-		/// Gets the invocations that this <see cref="JSRuntimeInvocationHandler{TResult}"/> has matched with.
-		/// </summary>
-		public IReadOnlyList<JSRuntimeInvocation> Invocations => _invocations.AsReadOnly();
-
 		/// <summary>
-		/// Creates an instance of a <see cref="JSRuntimeInvocationHandler{TResult}"/>.
+		/// Creates an instance of a <see cref="JSRuntimeInvocationHandler{TResult}"/> type.
 		/// </summary>
-		internal JSRuntimeInvocationHandler(string identifier, Func<IReadOnlyList<object?>, bool> matcher)
-		{
-			Identifier = identifier;
-			IsCatchAllHandler = identifier == CatchAllIdentifier;
-			_invocationMatcher = matcher;
-			_invocations = new List<JSRuntimeInvocation>();
-			_completionSource = new TaskCompletionSource<TResult>();
-		}
+		protected internal JSRuntimeInvocationHandler(string identifier, InvocationMatcher matcher) : base(identifier, matcher) { }
 
 		/// <summary>
 		/// Sets the <typeparamref name="TResult"/> result that invocations will receive.
 		/// </summary>
 		/// <param name="result"></param>
-		public void SetResult(TResult result)
-		{
-			if (_completionSource.Task.IsCompleted)
-				_completionSource = new TaskCompletionSource<TResult>();
-
-			_completionSource.SetResult(result);
-		}
-
-		/// <summary>
-		/// Sets the <typeparamref name="TException"/> exception that invocations will receive.
-		/// </summary>
-		/// <param name="exception"></param>
-		public void SetException<TException>(TException exception)
-			where TException : Exception
-		{
-			if (_completionSource.Task.IsCompleted)
-				_completionSource = new TaskCompletionSource<TResult>();
-
-			_completionSource.SetException(exception);
-		}
-
-		/// <summary>
-		/// Marks the <see cref="Task{TResult}"/> that invocations will receive as canceled.
-		/// </summary>
-		public void SetCanceled()
-		{
-			if (_completionSource.Task.IsCompleted)
-				_completionSource = new TaskCompletionSource<TResult>();
-
-			_completionSource.SetCanceled();
-		}
-
-		internal Task<TResult> RegisterInvocation(JSRuntimeInvocation invocation)
-		{
-			_invocations.Add(invocation);
-			return _completionSource.Task;
-		}
-
-		internal bool Matches(JSRuntimeInvocation invocation)
-		{
-			return Identifier.Equals(invocation.Identifier, StringComparison.Ordinal)
-				&& _invocationMatcher(invocation.Arguments);
-		}
+		public void SetResult(TResult result) => SetResultBase(result);
 	}
 
 	/// <summary>
 	/// Represents a handler for an invocation of a JavaScript function which returns nothing, with specific arguments.
 	/// </summary>
-	public class JSRuntimeInvocationHandler : JSRuntimeInvocationHandler<object>
+	public class JSRuntimeInvocationHandler : JSRuntimeInvocationHandlerBase<object>
 	{
 		/// <inheritdoc/>
-		public override bool IsVoidResultHandler { get; } = true;
+		public override sealed bool IsVoidResultHandler { get; } = true;
 
-		internal JSRuntimeInvocationHandler(string identifier, Func<IReadOnlyList<object?>, bool> matcher) : base(identifier, matcher)
-		{ }
+		/// <summary>
+		/// Creates an instance of a <see cref="JSRuntimeInvocationHandler"/> type.
+		/// </summary>
+		protected internal JSRuntimeInvocationHandler(string identifier, InvocationMatcher matcher) : base(identifier, matcher) { }
 
 		/// <summary>
 		/// Completes the current awaiting void invocation requests.
 		/// </summary>
-		public void SetVoidResult() => SetResult(default!);
+		public void SetVoidResult() => SetResultBase(default!);
 	}
 }