Implement IBuildEngine4 in the TaskRunner.

Author: KirillOsenkov

src/TaskRunner/BuildEngine.cs

@@ -1,10 +1,11 @@
 using System;
 using System.Collections;
+using System.Collections.Generic;
 using Microsoft.Build.Framework;
 
 namespace TaskRunner
 {
-    public class BuildEngine : IBuildEngine
+    public class BuildEngine : IBuildEngine4
     {
         public int ColumnNumberOfTaskNode => 0;
 
@@ -14,9 +15,26 @@ public class BuildEngine : IBuildEngine
 
         public string ProjectFileOfTaskNode => null;
 
+        public bool IsRunningMultipleNodes => false;
+
         public bool BuildProjectFile(string projectFileName, string[] targetNames, IDictionary globalProperties, IDictionary targetOutputs)
         {
-            throw new NotImplementedException();
+            throw new NotImplementedException(nameof(BuildProjectFile));
+        }
+
+        public bool BuildProjectFile(string projectFileName, string[] targetNames, IDictionary globalProperties, IDictionary targetOutputs, string toolsVersion)
+        {
+            throw new NotImplementedException(nameof(BuildProjectFile));
+        }
+
+        public BuildEngineResult BuildProjectFilesInParallel(string[] projectFileNames, string[] targetNames, IDictionary[] globalProperties, IList<string>[] removeGlobalProperties, string[] toolsVersion, bool returnTargetOutputs)
+        {
+            throw new NotImplementedException(nameof(BuildProjectFilesInParallel));
+        }
+
+        public bool BuildProjectFilesInParallel(string[] projectFileNames, string[] targetNames, IDictionary[] globalProperties, IDictionary[] targetOutputsPerProject, string[] toolsVersion, bool useResultsCache, bool unloadProjectsOnCompletion)
+        {
+            throw new NotImplementedException(nameof(BuildProjectFilesInParallel));
         }
 
         public void LogCustomEvent(CustomBuildEventArgs e)
@@ -38,5 +56,35 @@ public void LogWarningEvent(BuildWarningEventArgs e)
         {
             Console.WriteLine(e.Message);
         }
+
+        public void Reacquire()
+        {
+            throw new NotImplementedException(nameof(Reacquire));
+        }
+
+        public void Yield()
+        {
+            throw new NotImplementedException(nameof(Yield));
+        }
+
+        private Dictionary<object, object> registeredTaskObjects = new Dictionary<object, object>();
+
+        public void RegisterTaskObject(object key, object obj, RegisteredTaskObjectLifetime lifetime, bool allowEarlyCollection)
+        {
+            registeredTaskObjects[key] = obj;
+        }
+
+        public object GetRegisteredTaskObject(object key, RegisteredTaskObjectLifetime lifetime)
+        {
+            registeredTaskObjects.TryGetValue(key, out var value);
+            return value;
+        }
+
+        public object UnregisterTaskObject(object key, RegisteredTaskObjectLifetime lifetime)
+        {
+            registeredTaskObjects.TryGetValue(key, out var value);
+            registeredTaskObjects.Remove(key);
+            return value;
+        }
     }
 }