Add assembly redirects to MSBuild

Author: Daniel15

Diff for: src/React.MSBuild/AssemblyBindingRedirect.cs

@@ -0,0 +1,86 @@
+/*
+ *  Copyright (c) 2017-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 System.Collections.Generic;
+using System.Diagnostics;
+using System.IO;
+using System.Reflection;
+
+namespace React.MSBuild
+{
+	/// <summary>
+	/// Hacks around the fact that it's not possible to do assembly binding redirects in MSBuild.
+	/// 
+	/// https://github.com/Microsoft/msbuild/issues/1309
+	/// http://blog.slaks.net/2013-12-25/redirecting-assembly-loads-at-runtime/
+	/// </summary>
+	public static class AssemblyBindingRedirect
+	{
+		/// <summary>
+		/// Redirects that have been configured
+		/// </summary>
+		private static readonly Dictionary<string, Version> _redirects = new Dictionary<string, Version>();
+
+	    static AssemblyBindingRedirect()
+	    {
+			// This is in a static constructor because it needs to run as early as possible
+		    ConfigureRedirect("JavaScriptEngineSwitcher.Core");
+			AppDomain.CurrentDomain.AssemblyResolve += ResolveAssembly;
+		}
+
+		/// <summary>
+		/// Enables assembly binding redirects
+		/// </summary>
+	    public static void Enable()
+	    {
+			// Intentionally empty.  This is just meant to ensure the static constructor
+			// has run.
+		}
+
+		/// <summary>
+		/// Configures a redirect for the specified assembly. Redirects to the version in the bin directory.
+		/// </summary>
+		/// <param name="name">Name of the assembly to redirect</param>
+		private static void ConfigureRedirect(string name)
+		{
+			var currentAssemblyPath = Assembly.GetExecutingAssembly().Location;
+			var redirectAssemblyPath = Path.Combine(
+				Path.GetDirectoryName(currentAssemblyPath),
+				name + ".dll"
+			);
+
+			try
+			{
+				var realAssembly = Assembly.LoadFile(redirectAssemblyPath);
+				var version = realAssembly.GetName().Version;
+				_redirects[name] = version;
+			}
+			catch (Exception ex)
+			{
+				Trace.WriteLine("Warning: Could not determine version of " + name + " to use! " + ex.Message);
+			}
+		}
+
+		/// <summary>
+		/// Overrides assembly resolution to redirect if necessary.
+		/// </summary>
+		private static Assembly ResolveAssembly(object sender, ResolveEventArgs args)
+		{
+			var requestedAssembly = new AssemblyName(args.Name);
+
+			if (_redirects.ContainsKey(requestedAssembly.Name) && requestedAssembly.Version != _redirects[requestedAssembly.Name])
+			{
+				requestedAssembly.Version = _redirects[requestedAssembly.Name];
+				return Assembly.Load(requestedAssembly);
+			}
+			return null;
+		}
+	}
+}

Diff for: src/React.MSBuild/MSBuildHost.cs

@@ -9,6 +9,7 @@
 
 using System;
 using System.Diagnostics;
+using System.Reflection;
 
 namespace React.MSBuild
 {
@@ -36,6 +37,8 @@ public static bool EnsureInitialized()
 		/// <returns></returns>
 		private static bool Initialize()
 		{
+			AssemblyBindingRedirect.Enable();
+
 			// All "per-request" registrations should be singletons in MSBuild, since there's no
 			// such thing as a "request"
 			Initializer.Initialize(requestLifetimeRegistration: registration => registration.AsSingleton());

Diff for: src/React.Sample.Cassette/Web.config

@@ -62,7 +62,7 @@
 			</dependentAssembly>
 			<dependentAssembly>
 				<assemblyIdentity name="JavaScriptEngineSwitcher.Core" publicKeyToken="c608b2a8cc9e4472" culture="neutral" />
-				<bindingRedirect oldVersion="0.0.0.0-2.2.0.0" newVersion="2.2.0.0" />
+				<bindingRedirect oldVersion="0.0.0.0-2.4.9.0" newVersion="2.4.9.0" />
 			</dependentAssembly>
 		</assemblyBinding>
 	</runtime>

Diff for: src/React.Sample.Mvc4/Web.config

@@ -92,6 +92,10 @@
         <assemblyIdentity name="JavaScriptEngineSwitcher.Msie" publicKeyToken="c608b2a8cc9e4472" culture="neutral" />
         <bindingRedirect oldVersion="0.0.0.0-2.3.2.0" newVersion="2.3.2.0" />
       </dependentAssembly>
+      <dependentAssembly>
+        <assemblyIdentity name="MsieJavaScriptEngine" publicKeyToken="a3a2846a37ac0d3e" culture="neutral" />
+        <bindingRedirect oldVersion="0.0.0.0-2.2.2.0" newVersion="2.2.2.0" />
+      </dependentAssembly>
     </assemblyBinding>
   </runtime>