Imported Upstream version 5.4.0.167

Former-commit-id: 5624ac747d633e885131e8349322922b6a59baaa

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

@@ -0,0 +1,87 @@
+using System;
+using System.IO;
+using System.Xml;
+using System.Xml.Linq;
+using System.Linq;
+using System.Reflection;
+using System.Collections.Generic;
+using Microsoft.Build.Utilities; // Task
+using Microsoft.Build.Framework; // MessageImportance
+using Microsoft.NET.Build.Tasks; // LockFileCache
+using NuGet.ProjectModel; // LockFileTargetLibrary
+using NuGet.Frameworks; // NuGetFramework.Parse(targetframework)
+
+namespace ILLink.Tasks
+{
+	public class GetRuntimeLibraries : Task
+	{
+		/// <summary>
+		///   Path to the assets file.
+		/// </summary>
+		[Required]
+		public ITaskItem AssetsFilePath { get; set; }
+
+		/// <summary>
+		///   Target framework for which to get the platform
+		///   libraries.
+		/// </summary>
+		[Required]
+		public string TargetFramework { get; set; }
+
+		/// <summary>
+		///   Runtime identifier for which to get the platform
+		///   libraries.
+		/// </summary>
+		[Required]
+		public string RuntimeIdentifier { get; set; }
+
+		/// <summary>
+		///   Name of the library to consider the "platform"
+		///   library.
+		/// </summary>
+		[Required]
+		public string[] PackageNames { get; set; }
+
+		[Output]
+		public ITaskItem[] RuntimeLibraries { get; private set; }
+
+		public override bool Execute()
+		{
+			var lockFile = new LockFileCache(BuildEngine4).GetLockFile(AssetsFilePath.ItemSpec);
+			var lockFileTarget = lockFile.GetTarget(NuGetFramework.Parse(TargetFramework), RuntimeIdentifier);
+
+			if (lockFileTarget == null) {
+				var targetString = string.IsNullOrEmpty(RuntimeIdentifier) ? TargetFramework : $"{TargetFramework}/{RuntimeIdentifier}";
+
+				throw new Exception($"Missing target section {targetString} from assets file {AssetsFilePath}. Ensure you have restored this project previously.");
+			}
+
+			Dictionary<string, LockFileTargetLibrary> packages = new Dictionary<string, LockFileTargetLibrary>(lockFileTarget.Libraries.Count, StringComparer.OrdinalIgnoreCase);
+
+			foreach (var lib in lockFileTarget.Libraries) {
+				packages.Add(lib.Name, lib);
+			}
+
+			HashSet<string> packageNames = new HashSet<string>(PackageNames);
+			var rootPackages = lockFileTarget.Libraries.Where(l => packageNames.Contains(l.Name));
+
+			var packageQueue = new Queue<LockFileTargetLibrary>(rootPackages);
+
+			var libraries = new List<string>();
+			while (packageQueue.Count > 0) {
+				var package = packageQueue.Dequeue();
+				foreach (var lib in package.RuntimeAssemblies) {
+					libraries.Add(lib.ToString());
+				}
+
+				foreach (var dep in package.Dependencies.Select(d => d.Id)) {
+					packageQueue.Enqueue(packages[dep]);
+				}
+			}
+
+			RuntimeLibraries = libraries.Select(l => new TaskItem(l)).ToArray();
+
+			return true;
+		}
+	}
+}