Don't run MSBuild IoC registration if not actually in MSBuild

Author: Daniel15

src/React.MSBuild/AssemblyRegistration.cs

@@ -7,6 +7,7 @@
  *  of patent rights can be found in the PATENTS file in the same directory.
  */
 
+using System.Diagnostics;
 using React.TinyIoC;
 
 namespace React.MSBuild
@@ -23,6 +24,14 @@ public class AssemblyRegistration : IAssemblyRegistration
 		/// <param name="container">Container to register components in</param>
 		public void Register(TinyIoCContainer container)
 		{
+			if (!MSBuildHost.IsInMSBuild())
+			{
+				Trace.WriteLine(
+					"Warning: React.MSBuild AssemblyRegistration called, but not currently in MSBuild!"
+				);
+				return;
+			}
+
 			container.Register<ICache, NullCache>();
 			container.Register<IFileSystem, SimpleFileSystem>();
 		}

src/React.MSBuild/MSBuildHost.cs

@@ -8,6 +8,7 @@
  */
 
 using System;
+using System.Diagnostics;
 
 namespace React.MSBuild
 {
@@ -41,5 +42,21 @@ private static bool Initialize()
 
 			return true;
 		}
+
+		/// <summary>
+		/// Determines if the current process is MSBuild
+		/// </summary>
+		/// <returns><c>true</c> if we are currently in MSBuild</returns>
+		public static bool IsInMSBuild()
+		{
+			try
+			{
+				return Process.GetCurrentProcess().ProcessName.StartsWith("MSBuild");
+			}
+			catch (Exception)
+			{
+				return false;
+			}
+		}
 	}
 }