Use .NET Core 3.0 in Unit Tests Roslyn config.

ICSharpCode.Decompiler.Tests/Helpers/RemoveCompilerAttribute.cs

@@ -13,7 +13,7 @@ namespace ICSharpCode.Decompiler.Tests.Helpers
 			var section = (AttributeSection)attribute.Parent;
 			SimpleType type = attribute.Type as SimpleType;
 			if (section.AttributeTarget == "assembly" &&
-				(type.Identifier == "CompilationRelaxations" || type.Identifier == "RuntimeCompatibility" || type.Identifier == "SecurityPermission" || type.Identifier == "PermissionSet" || type.Identifier == "AssemblyVersion" || type.Identifier == "Debuggable"))
+				(type.Identifier == "CompilationRelaxations" || type.Identifier == "RuntimeCompatibility" || type.Identifier == "SecurityPermission" || type.Identifier == "PermissionSet" || type.Identifier == "AssemblyVersion" || type.Identifier == "Debuggable" || type.Identifier == "TargetFramework"))
 			{
 				attribute.Remove();
 				if (section.Attributes.Count == 0)

ICSharpCode.Decompiler.Tests/Helpers/Tester.cs

@@ -186,21 +186,36 @@ namespace ICSharpCode.Decompiler.Tests.Helpers
 				@"Reference Assemblies\Microsoft\Framework\.NETFramework\v4.7.2");
 		static readonly string thisAsmPath = Path.GetDirectoryName(typeof(Tester).Assembly.Location);
 
-		static readonly Lazy<IEnumerable<MetadataReference>> defaultReferences = new Lazy<IEnumerable<MetadataReference>>(delegate {
-			return new[]
-			{
-					MetadataReference.CreateFromFile(Path.Combine(refAsmPath, "Facades\\netstandard.dll")),
-					MetadataReference.CreateFromFile(Path.Combine(refAsmPath, "mscorlib.dll")),
-					MetadataReference.CreateFromFile(Path.Combine(refAsmPath, "System.dll")),
-					MetadataReference.CreateFromFile(Path.Combine(refAsmPath, "System.Core.dll")),
-					MetadataReference.CreateFromFile(Path.Combine(refAsmPath, @"Facades\System.Runtime.dll")),
-					MetadataReference.CreateFromFile(Path.Combine(refAsmPath, "System.Xml.dll")),
-					MetadataReference.CreateFromFile(Path.Combine(refAsmPath, "Microsoft.CSharp.dll")),
-					MetadataReference.CreateFromFile(typeof(ValueTuple).Assembly.Location),
-					MetadataReference.CreateFromFile(typeof(ValueTask).Assembly.Location),
-					MetadataReference.CreateFromFile(typeof(Span<>).Assembly.Location),
-			};
-		});
+		static readonly Lazy<IEnumerable<MetadataReference>> defaultReferences = new Lazy<IEnumerable<MetadataReference>>(GetDefaultReferences);
+
+		static readonly string[] references = new string[] {
+			"netstandard, Version=2.1.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51",
+			"mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089",
+			"System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089",
+			"System.Core, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089",
+			"System.Runtime, Version=4.2.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a",
+			"System.Xml, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a",
+			"Microsoft.CSharp, Version=4.0.4.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a",
+			"System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e",
+			"System.Console, Version=4.1.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"
+		};
+
+		const string targetFrameworkAttributeSnippet = @"
+
+[assembly: System.Runtime.Versioning.TargetFramework("".NETCoreApp, Version = v3.0"", FrameworkDisplayName = """")]
+
+";
+
+		static IEnumerable<MetadataReference> GetDefaultReferences()
+		{
+			DotNetCorePathFinder pathFinder = new DotNetCorePathFinder(new Version(3, 0));
+			foreach (var reference in references) {
+				var result = pathFinder.TryResolveDotNetCore(AssemblyNameReference.Parse(reference));
+				if (result != null) {
+					yield return MetadataReference.CreateFromFile(result);
+				}
+			}
+		}
 
 		static readonly Lazy<IEnumerable<MetadataReference>> visualBasic = new Lazy<IEnumerable<MetadataReference>>(delegate {
 			return new[] {
@@ -252,6 +267,7 @@ namespace ICSharpCode.Decompiler.Tests.Helpers
 					languageVersion: Microsoft.CodeAnalysis.CSharp.LanguageVersion.CSharp8
 				);
 				var syntaxTrees = sourceFileNames.Select(f => SyntaxFactory.ParseSyntaxTree(File.ReadAllText(f), parseOptions, path: f));
+				syntaxTrees = syntaxTrees.Concat(new[] { SyntaxFactory.ParseSyntaxTree(targetFrameworkAttributeSnippet) });
 				var references = defaultReferences.Value;
 				if (flags.HasFlag(CompilerOptions.ReferenceVisualBasic)) {
 					references = references.Concat(visualBasic.Value);
@@ -446,7 +462,7 @@ namespace ICSharpCode.Decompiler.Tests.Helpers
 				settings = new DecompilerSettings();
 			using (var file = new FileStream(assemblyFileName, FileMode.Open, FileAccess.Read)) {
 				var module = new PEFile(assemblyFileName, file, PEStreamOptions.PrefetchEntireImage);
-				var resolver = new UniversalAssemblyResolver(assemblyFileName, false,
+				var resolver = new UniversalAssemblyResolver(assemblyFileName, true,
 					module.Reader.DetectTargetFrameworkId(), PEStreamOptions.PrefetchMetadata);
 				resolver.AddSearchDirectory(Path.GetDirectoryName(typeof(Span<>).Assembly.Location));
 				var typeSystem = new DecompilerTypeSystem(module, resolver, settings);

ICSharpCode.Decompiler/Metadata/DotNetCorePathFinder.cs

@@ -62,15 +62,18 @@ namespace ICSharpCode.Decompiler.Metadata
 
 		readonly Dictionary<string, DotNetCorePackageInfo> packages;
 		ISet<string> packageBasePaths = new HashSet<string>(StringComparer.Ordinal);
-		readonly string assemblyName;
-		readonly string basePath;
 		readonly Version version;
 		readonly string dotnetBasePath = FindDotNetExeDirectory();
 
+		public DotNetCorePathFinder(Version version)
+		{
+			this.version = version;
+		}
+
 		public DotNetCorePathFinder(string parentAssemblyFileName, string targetFrameworkId, Version version, ReferenceLoadInfo loadInfo = null)
 		{
-			this.assemblyName = Path.GetFileNameWithoutExtension(parentAssemblyFileName);
-			this.basePath = Path.GetDirectoryName(parentAssemblyFileName);
+			string assemblyName = Path.GetFileNameWithoutExtension(parentAssemblyFileName);
+			string basePath = Path.GetDirectoryName(parentAssemblyFileName);
 			this.version = version;
 
 			var depsJsonFileName = Path.Combine(basePath, $"{assemblyName}.deps.json");

ICSharpCode.Decompiler/Metadata/UniversalAssemblyResolver.cs

@@ -101,7 +101,7 @@ namespace ICSharpCode.Decompiler.Metadata
 			AddSearchDirectory(baseDirectory);
 		}
 
-		(TargetFrameworkIdentifier, Version) ParseTargetFramework(string targetFramework)
+		static (TargetFrameworkIdentifier, Version) ParseTargetFramework(string targetFramework)
 		{
 			string[] tokens = targetFramework.Split(',');
 			TargetFrameworkIdentifier identifier;
@@ -131,7 +131,7 @@ namespace ICSharpCode.Decompiler.Metadata
 
 				switch (pair[0].Trim().ToUpperInvariant()) {
 					case "VERSION":
-						var versionString = pair[1].TrimStart('v');
+						var versionString = pair[1].TrimStart('v', ' ', '\t');
 						if (identifier == TargetFrameworkIdentifier.NETCoreApp ||
 							identifier == TargetFrameworkIdentifier.NETStandard)
 						{