Removed unused internals from the generated C#.

Fixes https://github.com/mono/CppSharp/issues/936.

Signed-off-by: Dimitar Dobrev <dpldobrev@protonmail.com>

src/AST/ASTVisitor.cs

@@ -1,5 +1,4 @@
-using System;
+using System.Collections.Generic;
-using System.Collections.Generic;
 using System.Linq;
 
 namespace CppSharp.AST
@@ -19,7 +18,6 @@ namespace CppSharp.AST
 
     public class AstVisitorOptions
     {
-        public bool VisitDeclaration = true;
         public bool VisitClassBases = true;
         public bool VisitClassFields = true;
         public bool VisitClassProperties = true;

src/AST/Class.cs

@@ -164,7 +164,7 @@ namespace CppSharp.AST
             {
                 foreach (var @base in Bases)
                 {
-                    if (@base.IsClass && @base.Class.IsDeclared)
+                    if (@base.IsClass && @base.Class.IsGenerated)
                         return @base.Class;
                 }
 
@@ -179,7 +179,7 @@ namespace CppSharp.AST
                 return HasBaseClass && !IsValueType
                        && Bases[0].Class != null
                        && !Bases[0].Class.IsValueType
-                       && Bases[0].Class.GenerationKind != GenerationKind.None;
+                       && Bases[0].Class.IsGenerated;
             }
         }
 

src/AST/ClassExtensions.cs

@@ -137,7 +137,7 @@ namespace CppSharp.AST
             if (@class.HasBaseClass)
                 @base = @class.Bases[0].Class;
 
-            var hasRefBase = @base != null && @base.IsRefType && @base.IsDeclared;
+            var hasRefBase = @base != null && @base.IsRefType && @base.IsGenerated;
 
             return hasRefBase;
         }

src/Generator/Driver.cs

@@ -337,6 +337,8 @@ namespace CppSharp
             if (Options.IsCSharpGenerator)
                 TranslationUnitPasses.AddPass(new SpecializationMethodsWithDependentPointersPass());
 
+            TranslationUnitPasses.AddPass(new MarkUsedClassInternalsPass());
+
             if (Options.GeneratorKind == GeneratorKind.CLI ||
                 Options.GeneratorKind == GeneratorKind.CSharp)
                 TranslationUnitPasses.RenameDeclsUpperCase(RenameTargets.Any &~ RenameTargets.Parameter);

src/Generator/Generators/CLI/CLISources.cs

@@ -707,7 +707,7 @@ namespace CppSharp.Generators.CLI
 
         private bool GenerateClassConstructorBase(Class @class, Method method = null)
         {
-            var hasBase = @class.HasBase && @class.Bases[0].IsClass && @class.Bases[0].Class.IsDeclared;
+            var hasBase = @class.HasBase && @class.Bases[0].IsClass && @class.Bases[0].Class.IsGenerated;
             if (!hasBase)
                 return false;
 

src/Generator/Generators/CSharp/CSharpSources.cs

@@ -327,7 +327,7 @@ namespace CppSharp.Generators.CSharp
 
         public override bool VisitClassDecl(Class @class)
         {
-            if (@class.IsIncomplete && !@class.IsOpaque)
+            if ((@class.IsIncomplete && !@class.IsOpaque) || @class.Ignore)
                 return false;
 
             if (@class.IsInterface)

src/Generator/Generators/CSharp/CSharpSourcesExtensions.cs

@@ -74,7 +74,7 @@ namespace CppSharp.Generators.CSharp
                 foreach (var parameter in @class.TemplateParameters)
                     gen.WriteLine($"var __{parameter.Name} = typeof({parameter.Name});");
 
-                foreach (var specialization in @class.Specializations.Where(s => !s.Ignore))
+                foreach (var specialization in @class.Specializations.Where(s => s.IsGenerated))
                 {
                     WriteTemplateSpecializationCheck(gen, @class, specialization);
                     gen.WriteStartBraceIndent();

src/Generator/Passes/MarkUsedClassInternalsPass.cs

@@ -0,0 +1,47 @@
+using CppSharp.AST;
+using CppSharp.AST.Extensions;
+
+namespace CppSharp.Passes
+{
+    public class MarkUsedClassInternalsPass : TranslationUnitPass
+    {
+        public MarkUsedClassInternalsPass()
+        {
+            VisitOptions.VisitClassBases = false;
+            VisitOptions.VisitClassMethods = false;
+            VisitOptions.VisitClassProperties = false;
+            VisitOptions.VisitEventParameters = false;
+            VisitOptions.VisitFunctionReturnType = false;
+            VisitOptions.VisitFunctionParameters = false;
+            VisitOptions.VisitNamespaceEnums = false;
+            VisitOptions.VisitNamespaceEvents = false;
+            VisitOptions.VisitNamespaceTemplates = false;
+            VisitOptions.VisitNamespaceVariables = false;
+            VisitOptions.VisitTemplateArguments = false;
+        }
+
+        public override bool VisitFieldDecl(Field field)
+        {
+            if (!base.VisitDeclaration(field))
+                return false;
+
+            Class @class;
+            if (field.Type.TryGetClass(out @class) && @class.Ignore)
+            {
+                DeclarationContext declarationContext = @class;
+                do
+                {
+                    if (declarationContext.Ignore)
+                        declarationContext.GenerationKind = GenerationKind.Internal;
+                    declarationContext = declarationContext.Namespace;
+                } while (declarationContext != null);
+
+                var specialization = @class as ClassTemplateSpecialization;
+                if (specialization?.TemplatedDecl.TemplatedClass.Ignore == true)
+                    specialization.TemplatedDecl.TemplatedClass.GenerationKind = GenerationKind.Internal;
+            }
+
+            return true;
+        }
+    }
+}