Some invalid CS is being written.

NuGet.config

@@ -1,7 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <configuration>
   <packageSources>
-    <clear />
     <!--Begin: Package sources managed by Dependency Flow automation. Do not edit the sources below.-->
     <!--  Begin: Package sources from dotnet-runtime -->
     <!--  End: Package sources from dotnet-runtime -->
@@ -12,6 +11,8 @@
     <add key="dotnet3.1" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet3.1/nuget/v3/index.json" />
     <add key="dotnet-public" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-public/nuget/v3/index.json" />
     <add key="nightly_iot_builds" value="https://pkgs.dev.azure.com/dotnet/IoT/_packaging/nightly_iot_builds/nuget/v3/index.json" />
+    <add key="local" value="C:\projects\ILSpy\ICSharpCode.Decompiler\bin\Debug" />
+
   </packageSources>
   <disabledPackageSources />
 </configuration>

src/devices/Arduino/FirmataDevice.cs

@@ -1209,7 +1209,7 @@ internal void DisableAnalogReporting(int pinNumber, int analogChannel)
                     pwmCommandSequence.WriteByte((byte)0);
                     pwmCommandSequence.WriteByte((byte)FirmataCommand.END_SYSEX);
                     SendCommand(pwmCommandSequence);
-        }
+                }
             }
         }
 

tools/ArduinoCsCompiler/ArduinoCsCompiler.csproj

@@ -24,15 +24,16 @@
    </ItemGroup>
 
   <ItemGroup>
+    <PackageReference Include="ICSharpCode.Decompiler" Version="9.0.0.7618-preview1" />
     <PackageReference Include="Microsoft.CodeAnalysis.CSharp.Scripting" Version="4.8.0" />
   </ItemGroup>
   <ItemGroup Condition="$(Configuration)=='Debug'">
     <ProjectReference Include="..\..\src\devices\Arduino\Arduino.csproj" />
     <ProjectReference Include="..\..\src\System.Device.Gpio\System.Device.Gpio.csproj" />
   </ItemGroup>
   <ItemGroup Condition="$(Configuration)!='Debug'">
-    <ProjectReference Include="..\..\src\System.Device.Gpio\System.Device.Gpio.csproj"/>
-    <ProjectReference Include="..\..\src\Iot.Device.Bindings\Iot.Device.Bindings.csproj"/>
+    <ProjectReference Include="..\..\src\System.Device.Gpio\System.Device.Gpio.csproj" />
+    <ProjectReference Include="..\..\src\Iot.Device.Bindings\Iot.Device.Bindings.csproj" />
   </ItemGroup>
 
   <ItemGroup>
@@ -41,4 +42,9 @@
     </AssemblyAttribute>
   </ItemGroup>
 
+  <ItemGroup>
+    <Compile Include="NanoGenerator\ClassWrapper.cs" />
+    <Compile Include="NanoGenerator\FieldWrapper.cs" />
+  </ItemGroup>
+
 </Project>

tools/ArduinoCsCompiler/ClassDeclaration.cs

@@ -21,6 +21,8 @@ public ClassDeclaration(Type type, int dynamicSize, int staticSize, int newToken
             NewToken = newToken;
             _interfaces = interfaces;
             Name = type.ClassSignature(true);
+            Namespace = type.Namespace ?? string.Empty;
+            SimpleName = type.Name;
             ReadOnly = false;
         }
 
@@ -38,6 +40,10 @@ public bool ReadOnly
             internal set;
         }
 
+        public string Namespace { get; }
+
+        public string SimpleName { get; }
+
         public int NewToken
         {
             get;

tools/ArduinoCsCompiler/ExecutionSet.cs

@@ -1506,11 +1506,8 @@ public void SuppressNamespace(string namespacePrefix, bool includingSubNamespace
 
         public void WritePatchedCodeFile(string file, IlCapabilities ilCapabilities)
         {
-            using TextWriter tw = new StreamWriter("output.il");
-            foreach (var cls in _classes)
-            {
-                IlWriter.WriteClass(tw, cls, this);
-            }
+            var writer = new IlWriter(this, ilCapabilities);
+            writer.Write(CompilerSettings.ProcessName, file);
         }
 
         public void WriteMapFile(string tokenMapFile, IlCapabilities ilCapabilities)
@@ -1729,5 +1726,15 @@ public void AddReverseFieldLookupTable()
 
             _logger.LogDebug($"Got {fieldOrCtorTokenToClass.Count} members in reverse lookup index");
         }
+
+        /// <summary>
+        /// Returns the class declaration for a standard class type
+        /// </summary>
+        /// <param name="type">The type to search</param>
+        /// <returns>The class or null</returns>
+        public ClassDeclaration? GetClass(Type? type)
+        {
+            return Classes.FirstOrDefault(x => x.TheType == type);
+        }
     }
 }

tools/ArduinoCsCompiler/Frontend/CompilerRun.cs

@@ -111,11 +111,13 @@ public override bool RunCommand()
 
                 RunCompiler(inputInfo);
             }
+#if !DEBUG
             catch (Exception x) when (!(x is NullReferenceException))
             {
                 Logger.LogError(x.Message);
                 return false;
             }
+#endif
             finally
             {
                 board?.Dispose();

tools/ArduinoCsCompiler/IlWriter.cs

@@ -2,17 +2,35 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Reflection;
+using System.Reflection.Metadata;
 using System.Text;
 using System.Threading.Tasks;
+using System.Xml;
+using ArduinoCsCompiler.NanoGenerator;
+using ICSharpCode.Decompiler;
+using ICSharpCode.Decompiler.CSharp;
+using ICSharpCode.Decompiler.CSharp.OutputVisitor;
+using ICSharpCode.Decompiler.CSharp.Syntax;
+using ICSharpCode.Decompiler.TypeSystem;
 
 namespace ArduinoCsCompiler
 {
     public class IlWriter
     {
+        private readonly ExecutionSet _executionSet;
+        private readonly IlCapabilities _ilCapabilities;
+
+        public IlWriter(ExecutionSet executionSet, IlCapabilities ilCapabilities)
+        {
+            _executionSet = executionSet;
+            _ilCapabilities = ilCapabilities;
+        }
+
         public static void WriteMethodHeader(TextWriter w, ArduinoMethodDeclaration code)
         {
             string signature = code.MethodBase.MethodSignature(false, true);
@@ -53,5 +71,38 @@ public static void WriteMethod(TextWriter w, ArduinoMethodDeclaration code, Exec
             w.WriteLine(methodBody);
             w.WriteLine("}");
         }
+
+        public void Write(string sourceFile, string outFile)
+        {
+            var settings = new DecompilerSettings()
+            {
+                UseSdkStyleProjectFormat = false,
+            };
+
+            using TextWriter tw = new StreamWriter("output.cs");
+            SyntaxTree tree = new SyntaxTree();
+            var node = new NamespaceDeclaration("Decompiled");
+            tree.AddChild(node, SyntaxTree.MemberRole);
+
+            foreach (var cls in _executionSet.Classes)
+            {
+                var typeSystemAstBuilder = new TypeSystemAstBuilder();
+                var wrapped = new ClassWrapper(cls, _executionSet);
+                EntityDeclaration decl = typeSystemAstBuilder.ConvertEntity(wrapped);
+                node.AddChild(decl, SyntaxTree.MemberRole);
+                foreach (var member in cls.Members)
+                {
+                    if (member.Field != null)
+                    {
+                        var fieldWrapped = new FieldWrapper(cls, member, _executionSet);
+                        EntityDeclaration fld = typeSystemAstBuilder.ConvertEntity(fieldWrapped);
+                        decl.AddChild(fld, Roles.TypeMemberRole);
+                    }
+                }
+            }
+
+            var formatting = FormattingOptionsFactory.CreateSharpDevelop();
+            tree.AcceptVisitor(new CSharpOutputVisitor(tw, formatting));
+        }
     }
 }