Update ICSharpCode.Decompiler to 4.0-beta1

build/Targets/Packages.props

@@ -14,7 +14,7 @@
     <dotnetxunitVersion>2.3.1</dotnetxunitVersion>
     <FakeSignVersion>0.9.2</FakeSignVersion>
     <HumanizerCoreVersion>2.2.0</HumanizerCoreVersion>
-    <ICSharpCodeDecompilerVersion>3.1.0.3652</ICSharpCodeDecompilerVersion>
+    <ICSharpCodeDecompilerVersion>4.0.0.4285-beta1</ICSharpCodeDecompilerVersion>
     <LibGit2SharpVersion>0.22.0</LibGit2SharpVersion>
     <MicroBuildCoreVersion>0.2.0</MicroBuildCoreVersion>
     <MicroBuildCoreSentinelVersion>1.0.0</MicroBuildCoreSentinelVersion>

build/config/SignToolData.json

@@ -191,10 +191,6 @@
     "Microsoft.VisualStudio.Threading.resources.dll",
     "Microsoft.VisualStudio.Validation.dll",
     "Microsoft.Win32.Primitives.dll",
-    "Mono.Cecil.dll",
-    "Mono.Cecil.Mdb.dll",
-    "Mono.Cecil.Pdb.dll",
-    "Mono.Cecil.Rocks.dll",
     "Nerdbank.FullDuplexStream.dll",
     "Newtonsoft.Json.dll",
     "NuGet.CommandLine.2.8.5.nupkg",

src/EditorFeatures/Core/Implementation/MetadataAsSource/MetadataAsSourceFileService.cs

@@ -7,20 +7,21 @@
 using System.Globalization;
 using System.IO;
 using System.Linq;
+using System.Reflection.PortableExecutable;
 using System.Runtime.CompilerServices;
 using System.Threading;
 using System.Threading.Tasks;
 using ICSharpCode.Decompiler;
 using ICSharpCode.Decompiler.CSharp;
 using ICSharpCode.Decompiler.CSharp.Transforms;
+using ICSharpCode.Decompiler.Metadata;
 using ICSharpCode.Decompiler.TypeSystem;
 using Microsoft.CodeAnalysis.ErrorReporting;
 using Microsoft.CodeAnalysis.MetadataAsSource;
 using Microsoft.CodeAnalysis.Shared.Extensions;
 using Microsoft.CodeAnalysis.SymbolMapping;
 using Microsoft.CodeAnalysis.Text;
 using Microsoft.VisualStudio.Text;
-using Mono.Cecil;
 using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis.Editor.Implementation.MetadataAsSource
@@ -224,10 +225,11 @@ private async Task<Document> DecompileSymbolAsync(Document temporaryDocument, IS
             }
 
             // Load the assembly.
-            var assemblyDefinition = AssemblyDefinition.ReadAssembly(assemblyLocation, new ReaderParameters() { AssemblyResolver = new RoslynAssemblyResolver(compilation) });
+            var pefile = new PEFile(assemblyLocation, PEStreamOptions.PrefetchEntireImage);
 
             // Initialize a decompiler with default settings.
-            var decompiler = new CSharpDecompiler(assemblyDefinition.MainModule, new DecompilerSettings());
+            var settings = new DecompilerSettings(LanguageVersion.Latest);
+            var decompiler = new CSharpDecompiler(pefile, new RoslynAssemblyResolver(compilation), settings);
             // Escape invalid identifiers to prevent Roslyn from failing to parse the generated code.
             // (This happens for example, when there is compiler-generated code that is not yet recognized/transformed by the decompiler.)
             decompiler.AstTransforms.Add(new EscapeInvalidIdentifiers());
@@ -238,8 +240,8 @@ private async Task<Document> DecompileSymbolAsync(Document temporaryDocument, IS
 
             // Add header to match output of metadata-only view.
             // (This also makes debugging easier, because you can see which assembly was decompiled inside VS.)
-            var header = $"#region {FeaturesResources.Assembly} {assemblyDefinition.FullName}" + Environment.NewLine
-                + $"// {assemblyDefinition.MainModule.FileName}" + Environment.NewLine
+            var header = $"#region {FeaturesResources.Assembly} {pefile.FullName}" + Environment.NewLine
+                + $"// {assemblyLocation}" + Environment.NewLine
                 + $"// Decompiled with ICSharpCode.Decompiler {decompilerVersion.FileVersion}" + Environment.NewLine
                 + "#endregion" + Environment.NewLine;
 
@@ -251,46 +253,56 @@ private async Task<Document> DecompileSymbolAsync(Document temporaryDocument, IS
         private class RoslynAssemblyResolver : IAssemblyResolver
         {
             private readonly Compilation parentCompilation;
+            private static readonly Version zeroVersion = new Version(0, 0, 0, 0);
 
             public RoslynAssemblyResolver(Compilation parentCompilation)
             {
                 this.parentCompilation = parentCompilation;
             }
 
-            public AssemblyDefinition Resolve(AssemblyNameReference name)
-            {
-                return Resolve(name, new ReaderParameters());
-            }
-
-            public AssemblyDefinition Resolve(AssemblyNameReference name, ReaderParameters parameters)
+            public PEFile Resolve(IAssemblyReference name)
             {
                 foreach (var assembly in parentCompilation.GetReferencedAssemblySymbols())
                 {
+                    // First, find the correct IAssemblySymbol by name and PublicKeyToken.
                     if (assembly.Identity.Name != name.Name
                         || !assembly.Identity.PublicKeyToken.SequenceEqual(name.PublicKeyToken ?? Array.Empty<byte>()))
                     {
                         continue;
                     }
 
-                    if (assembly.Identity.Version != name.Version
+                    // Normally we skip versions that do not match, except if the reference is "mscorlib" (see comments below)
+                    // or if the name.Version is '0.0.0.0'. This is because we require the metadata of all transitive references
+                    // and modules, to achieve best decompilation results.
+                    // In the case of .NET Standard projects for example, the 'netstandard' reference contains no references
+                    // with actual versions. All versions are '0.0.0.0', therefore we have to ignore those version numbers,
+                    // and can just use the references provided by Roslyn instead.
+                    if (assembly.Identity.Version != name.Version && name.Version != zeroVersion
                         && !string.Equals("mscorlib", assembly.Identity.Name, StringComparison.OrdinalIgnoreCase))
                     {
                         // MSBuild treats mscorlib special for the purpose of assembly resolution/unification, where all
                         // versions of the assembly are considered equal. The same policy is adopted here.
                         continue;
                     }
 
-                    // reference assemblies should be fine here...
+                    // reference assemblies should be fine here, we only need the metadata of references.
                     var reference = parentCompilation.GetMetadataReference(assembly);
-                    return AssemblyDefinition.ReadAssembly(reference.Display);
+                    return new PEFile(reference.Display, PEStreamOptions.PrefetchMetadata);
                 }
 
                 // not found
                 return null;
             }
 
-            public void Dispose()
+            public PEFile ResolveModule(PEFile mainModule, string moduleName)
             {
+                // Primitive implementation to support multi-module assemblies
+                // where all modules are located next to the main module.
+                string baseDirectory = Path.GetDirectoryName(mainModule.FileName);
+                string moduleFileName = Path.Combine(baseDirectory, moduleName);
+                if (!File.Exists(moduleFileName))
+                    return null;
+                return new PEFile(moduleFileName, PEStreamOptions.PrefetchMetadata);
             }
         }
 

src/Setup/DevDivInsertionFiles/BuildDevDivInsertionFiles.vb

@@ -1,4 +1,4 @@
-Imports System.IO.Packaging
+Imports System.IO.Packaging
 Imports System.IO
 Imports System.Threading
 Imports Newtonsoft.Json
@@ -574,10 +574,6 @@ Public Class BuildDevDivInsertionFiles
         add("Vsix\Roslyn.VisualStudio.Setup\System.Composition.Hosting.dll")
         add("Vsix\Roslyn.VisualStudio.Setup\System.Composition.TypedParts.dll")
         add("Vsix\Roslyn.VisualStudio.Setup\System.Threading.Tasks.Extensions.dll")
-        add("Vsix\Roslyn.VisualStudio.Setup\Mono.Cecil.dll")
-        add("Vsix\Roslyn.VisualStudio.Setup\Mono.Cecil.Mdb.dll")
-        add("Vsix\Roslyn.VisualStudio.Setup\Mono.Cecil.Pdb.dll")
-        add("Vsix\Roslyn.VisualStudio.Setup\Mono.Cecil.Rocks.dll")
         add("Vsix\Roslyn.VisualStudio.Setup\ICSharpCode.Decompiler.dll")
         add("Dlls\Microsoft.CodeAnalysis.VisualBasic.ExpressionCompiler\Microsoft.CodeAnalysis.VisualBasic.ExpressionEvaluator.ExpressionCompiler.vsdconfig")
         add("Dlls\Microsoft.CodeAnalysis.VisualBasic.ResultProvider\Microsoft.CodeAnalysis.VisualBasic.ExpressionEvaluator.ResultProvider.vsdconfig")
@@ -945,4 +941,4 @@ set DEVPATH=%RoslynToolsRoot%;%DEVPATH%"
             Console.WriteLine(s)
         End If
     End Sub
-End Class
+End Class

src/VisualStudio/Setup/AssemblyRedirects.cs

@@ -44,7 +44,6 @@
 [assembly: ProvideCodeBase(CodeBase = @"$PackageFolder$\System.Threading.Tasks.Extensions.dll")]
 [assembly: ProvideCodeBase(CodeBase = @"$PackageFolder$\Humanizer.dll")]
 
-[assembly: ProvideCodeBase(CodeBase = @"$PackageFolder$\Mono.Cecil.dll")]
 [assembly: ProvideCodeBase(CodeBase = @"$PackageFolder$\ICSharpCode.Decompiler.dll")]
 
 [assembly: ProvideBindingRedirection(

src/VisualStudio/Setup/Roslyn.VisualStudio.Setup.csproj

@@ -237,7 +237,6 @@
     <NuGetPackageToIncludeInVsix Include="System.Composition.Hosting" />
     <NuGetPackageToIncludeInVsix Include="System.Threading.Tasks.Extensions" />
     <NuGetPackageToIncludeInVsix Include="ICSharpCode.Decompiler" />
-    <NuGetPackageToIncludeInVsix Include="Mono.Cecil" />
   </ItemGroup>
   <ItemGroup>
     <VSIXSourceItem Include="$(NuGetPackageRoot)\SQLitePCLRaw.bundle_green\1.1.2\lib\net45\SQLitePCLRaw.batteries_green.dll" />