Add tests and update sample

Author: dustinsoftware

src/React.Core/IReactSiteConfiguration.cs

@@ -1,4 +1,4 @@
-/*
+/*
  *  Copyright (c) 2014-Present, Facebook, Inc.
  *  All rights reserved.
  *
@@ -178,12 +178,20 @@ public interface IReactSiteConfiguration
 		/// <summary>
 		/// Disables server-side rendering. This is useful when debugging your scripts.
 		/// </summary>
-		IReactSiteConfiguration DisableServerSideRendering();
-
+		IReactSiteConfiguration DisableServerSideRendering();
+
 		/// <summary>
-		/// Handle an exception caught during server-render of a component.
+		/// An exception handler which will be called if a render exception is thrown.
 		/// If unset, unhandled exceptions will be thrown for all component renders.
 		/// </summary>
-		Action<Exception> HandleRenderException { get; set; }
+		Action<Exception> ExceptionHandler { get; set; }
+
+		/// <summary>
+		/// Sets an exception handler which will be called if a render exception is thrown.
+		/// If unset, unhandled exceptions will be thrown for all component renders.
+		/// </summary>
+		/// <param name="handler"></param>
+		/// <returns></returns>
+		IReactSiteConfiguration SetExceptionHandler(Action<Exception> handler);
 	}
 }

src/React.Core/ReactComponent.cs

@@ -1,4 +1,4 @@
-/*
+/*
  *  Copyright (c) 2014-Present, Facebook, Inc.
  *  All rights reserved.
  *
@@ -132,15 +132,15 @@ public virtual string RenderHtml(bool renderContainerOnly = false, bool renderSe
 				}
 				catch (JsRuntimeException ex)
 				{
-					if (_configuration.HandleRenderException == null) {
+					if (_configuration.ExceptionHandler == null) {
 						throw new ReactServerRenderingException(string.Format(
 							"Error while rendering \"{0}\" to \"{2}\": {1}",
 							ComponentName,
 							ex.Message,
 							ContainerId
 						));
 					}
-					_configuration.HandleRenderException(ex);
+					_configuration.ExceptionHandler(ex);
 				}
 			}
 

src/React.Core/ReactSiteConfiguration.cs

@@ -1,4 +1,4 @@
-/*
+/*
  *  Copyright (c) 2014-Present, Facebook, Inc.
  *  All rights reserved.
  *
@@ -306,6 +306,17 @@ public IReactSiteConfiguration DisableServerSideRendering()
 		/// Handle an exception caught during server-render of a component.
 		/// If unset, unhandled exceptions will be thrown for all component renders.
 		/// </summary>
-		public Action<Exception> HandleRenderException { get; set; }
+		public Action<Exception> ExceptionHandler { get; set; }
+
+		/// <summary>
+		/// 
+		/// </summary>
+		/// <param name="handler"></param>
+		/// <returns></returns>
+		public IReactSiteConfiguration SetExceptionHandler(Action<Exception> handler)
+		{
+			ExceptionHandler = handler;
+			return this;
+		}
 	}
 }

src/React.Sample.CoreMvc/Startup.cs

@@ -20,15 +20,16 @@ namespace React.Sample.CoreMvc
 {
 	public class Startup
 	{
-		public Startup(IHostingEnvironment env)
-		{
-			// Setup configuration sources.
+		public Startup(IHostingEnvironment env, ILogger<Startup> logger)
+		{
+			// Setup configuration sources.
 			var builder = new ConfigurationBuilder().AddEnvironmentVariables();
-
+			Logger = logger;
 			Configuration = builder.Build();
 		}
 
-		public IConfiguration Configuration { get; set; }
+		public IConfiguration Configuration { get; set; }
+		public ILogger<Startup> Logger { get; set; }
 
 		// This method gets called by the runtime.
 		public IServiceProvider ConfigureServices(IServiceCollection services)
@@ -69,8 +70,12 @@ public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerF
 			{
 				config
 					.SetReuseJavaScriptEngines(true)
-					.AddScript("~/js/Sample.jsx")
-					.SetUseDebugReact(true);
+					.AddScript("~/js/Sample.jsx")
+					.SetExceptionHandler(ex =>
+					{
+						Logger.LogError("React component exception thrown!" + ex.ToString());
+					})
+					.SetUseDebugReact(true);
 			});
 
 			// Add static files to the request pipeline.

tests/React.Tests/Core/ReactComponentTest.cs

@@ -1,16 +1,18 @@
-/*
+/*
  *  Copyright (c) 2014-Present, Facebook, Inc.
  *  All rights reserved.
  *
  *  This source code is licensed under the BSD-style license found in the
  *  LICENSE file in the root directory of this source tree. An additional grant
  *  of patent rights can be found in the PATENTS file in the same directory.
- */
-
+ */
+
+using System;
+using JavaScriptEngineSwitcher.Core;
 using Moq;
-using Xunit;
 using React.Exceptions;
-
+using Xunit;
+
 namespace React.Tests.Core
 {
 	public class ReactComponentTest
@@ -190,7 +192,44 @@ public void GeneratesContainerIdIfNotProvided()
 
 			var component = new ReactComponent(environment.Object, config.Object, "Foo", null);
 			Assert.StartsWith("react_", component.ContainerId);
-		}
+		}
+
+		[Fact]
+		public void ExceptionThrownIsHandled()
+		{
+			var environment = new Mock<IReactEnvironment>();
+			environment.Setup(x => x.Execute<bool>("typeof Foo !== 'undefined'")).Returns(true);
+			environment.Setup(x => x.Execute<string>(@"ReactDOMServer.renderToString(React.createElement(Foo, {""hello"":""World""}))"))
+				.Throws(new JsRuntimeException("'undefined' is not an object"));
+
+			var config = new Mock<IReactSiteConfiguration>();
+			config.Setup(x => x.UseServerSideRendering).Returns(true);
 
+			var component = new ReactComponent(environment.Object, config.Object, "Foo", "container")
+			{
+				Props = new { hello = "World" }
+			};
+
+			// Default behavior
+			bool exceptionCaught = false;
+			try
+			{
+				component.RenderHtml();
+			}
+			catch (ReactServerRenderingException)
+			{
+				exceptionCaught = true;
+			}
+
+			Assert.True(exceptionCaught);
+
+			// Custom exception handler set
+			Exception caughtException = null;
+			config.Setup(x => x.ExceptionHandler).Returns(ex => caughtException = ex);
+
+			var result = component.RenderHtml();
+			Assert.Equal(@"<div id=""container""></div>", result);
+			Assert.NotNull(caughtException);
+		}
 	}
 }