Imported Upstream version 5.8.0.22

Former-commit-id: df344e34b07851d296efb3e6604c8db42b6f7aa3

external/linker/corebuild/integration/ILLink.Tasks/ComputeRemovedAssemblies.cs

@@ -0,0 +1,45 @@
+using System;
+using System.IO;
+using System.Linq;
+using System.Collections.Generic;
+using Microsoft.Build.Utilities;
+using Microsoft.Build.Framework;
+
+namespace ILLink.Tasks
+{
+	public class ComputeRemovedAssemblies : Task
+	{
+		/// <summary>
+		///   The paths to the inputs to the linker.
+		/// </summary>
+		[Required]
+		public ITaskItem[] InputAssemblies { get; set; }
+
+		/// <summary>
+		///   The paths to the linked assemblies.
+		/// </summary>
+		[Required]
+		public ITaskItem[] KeptAssemblies { get; set; }
+
+		/// <summary>
+		///   The set of assemblies in the inputs that weren't kept by
+		///   the linker. These items include the full metadata from
+		///   the input assemblies, and only the filenames of the
+		///   inputs are used to determine which assemblies were
+		///   removed.
+		/// </summary>
+		[Output]
+		public ITaskItem[] RemovedAssemblies { get; set; }
+
+		public override bool Execute()
+		{
+			var keptAssemblyNames = new HashSet<string> (
+				KeptAssemblies.Select(i => Path.GetFileName(i.ItemSpec))
+			);
+			RemovedAssemblies = InputAssemblies.Where(i =>
+				!keptAssemblyNames.Contains(Path.GetFileName(i.ItemSpec))
+			).ToArray();
+			return true;
+		}
+	}
+}