Make NumberOfCompilerGeneratedGenerics immutable and rename to NumberOfCompilerGeneratedTypeParameters

ICSharpCode.Decompiler/CSharp/CallBuilder.cs

@@ -197,7 +197,7 @@ namespace ICSharpCode.Decompiler.CSharp
 			} else if (localFunction != null) {
 				var ide = new IdentifierExpression(localFunction.Name);
 				if (method.TypeArguments.Count > 0) {
-					int skipCount = localFunction.ReducedMethod.NumberOfCompilerGeneratedGenerics;
+					int skipCount = localFunction.ReducedMethod.NumberOfCompilerGeneratedTypeParameters;
 					ide.TypeArguments.AddRange(method.TypeArguments.Skip(skipCount).Select(expressionBuilder.ConvertType));
 				}
 				target = ide.WithoutILInstruction()
@@ -1401,7 +1401,7 @@ namespace ICSharpCode.Decompiler.CSharp
 				if ((step & 2) != 0) {
 					int skipCount = 0;
 					if (localFunction != null && method.TypeArguments.Count > 0) {
-						skipCount = localFunction.ReducedMethod.NumberOfCompilerGeneratedGenerics;
+						skipCount = localFunction.ReducedMethod.NumberOfCompilerGeneratedTypeParameters;
 					}
 					ide.TypeArguments.AddRange(method.TypeArguments.Skip(skipCount).Select(expressionBuilder.ConvertType));
 				}

ICSharpCode.Decompiler/CSharp/StatementBuilder.cs

@@ -990,7 +990,7 @@ namespace ICSharpCode.Decompiler.CSharp
 				if (function.Method.TypeParameters.Count > 0) {
 					var astBuilder = exprBuilder.astBuilder;
 					if (astBuilder.ShowTypeParameters) {
-						int skipCount = function.ReducedMethod.NumberOfCompilerGeneratedGenerics;
+						int skipCount = function.ReducedMethod.NumberOfCompilerGeneratedTypeParameters;
 						stmt.TypeParameters.AddRange(function.Method.TypeParameters.Skip(skipCount).Select(t => astBuilder.ConvertTypeParameter(t)));
 						if (astBuilder.ShowTypeParameterConstraints) {
 							stmt.Constraints.AddRange(function.Method.TypeParameters.Skip(skipCount).Select(t => astBuilder.ConvertTypeParameterConstraint(t)).Where(c => c != null));

ICSharpCode.Decompiler/IL/Transforms/LocalFunctionDecompiler.cs

@@ -115,7 +115,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 						declaringFunction.LocalFunctions.Add(localFunction);
 					}
 
-					if (TryValidateSkipCount(info, out int skipCount) && skipCount != localFunction.ReducedMethod.NumberOfCompilerGeneratedGenerics) {
+					if (TryValidateSkipCount(info, out int skipCount) && skipCount != localFunction.ReducedMethod.NumberOfCompilerGeneratedTypeParameters) {
 						Debug.Assert(false);
 						function.Warnings.Add($"Could not decode local function '{info.Method}'");
 						if (localFunction.DeclarationScope != function.Body && localFunction.DeclarationScope.Parent is ILFunction declaringFunction) {
@@ -228,8 +228,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			var nestedContext = new ILTransformContext(context, function);
 			function.RunTransforms(CSharpDecompiler.GetILTransforms().TakeWhile(t => !(t is LocalFunctionDecompiler)), nestedContext);
 			function.DeclarationScope = null;
-			function.ReducedMethod = ReduceToLocalFunction(function.Method);
-			function.ReducedMethod.NumberOfCompilerGeneratedGenerics = skipCount;
+			function.ReducedMethod = ReduceToLocalFunction(function.Method, skipCount);
 			return function;
 		}
 
@@ -324,7 +323,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			return inst;
 		}
 
-		LocalFunctionMethod ReduceToLocalFunction(IMethod method)
+		LocalFunctionMethod ReduceToLocalFunction(IMethod method, int skipCount)
 		{
 			int parametersToRemove = 0;
 			for (int i = method.Parameters.Count - 1; i >= 0; i--) {
@@ -332,7 +331,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 					break;
 				parametersToRemove++;
 			}
-			return new LocalFunctionMethod(method, parametersToRemove);
+			return new LocalFunctionMethod(method, parametersToRemove, skipCount);
 		}
 
 		static void TransformToLocalFunctionReference(ILFunction function, CallInstruction useSite)

ICSharpCode.Decompiler/TypeSystem/Implementation/LocalFunctionMethod.cs

@@ -31,20 +31,24 @@ namespace ICSharpCode.Decompiler.TypeSystem.Implementation
 	{
 		readonly IMethod baseMethod;
 
-		public LocalFunctionMethod(IMethod baseMethod, int numberOfCompilerGeneratedParameters)
+		public LocalFunctionMethod(IMethod baseMethod, int numberOfCompilerGeneratedParameters, int numberOfCompilerGeneratedTypeParameters)
 		{
+			if (baseMethod == null)
+				throw new ArgumentNullException(nameof(baseMethod));
+			if (baseMethod is SpecializedMethod)
+				throw new ArgumentException("Must not be a specialized method!", nameof(baseMethod));
 			this.baseMethod = baseMethod;
 			this.NumberOfCompilerGeneratedParameters = numberOfCompilerGeneratedParameters;
+			this.NumberOfCompilerGeneratedTypeParameters = numberOfCompilerGeneratedTypeParameters;
 		}
 
-
 		public bool Equals(IMember obj, TypeVisitor typeNormalization)
 		{
 			if (!(obj is LocalFunctionMethod other))
 				return false;
 			return baseMethod.Equals(other.baseMethod, typeNormalization)
 				&& NumberOfCompilerGeneratedParameters == other.NumberOfCompilerGeneratedParameters
-				&& NumberOfCompilerGeneratedGenerics == other.NumberOfCompilerGeneratedGenerics;
+				&& NumberOfCompilerGeneratedTypeParameters == other.NumberOfCompilerGeneratedTypeParameters;
 		}
 
 		public override bool Equals(object obj)
@@ -53,24 +57,22 @@ namespace ICSharpCode.Decompiler.TypeSystem.Implementation
 				return false;
 			return baseMethod.Equals(other.baseMethod)
 				&& NumberOfCompilerGeneratedParameters == other.NumberOfCompilerGeneratedParameters
-				&& NumberOfCompilerGeneratedGenerics == other.NumberOfCompilerGeneratedGenerics;
+				&& NumberOfCompilerGeneratedTypeParameters == other.NumberOfCompilerGeneratedTypeParameters;
 		}
 		
 		public override int GetHashCode()
 		{
-			unchecked {
-				return baseMethod.GetHashCode() + NumberOfCompilerGeneratedParameters + 1;
-			}
+			return baseMethod.GetHashCode();
 		}
 
 		public override string ToString()
 		{
-			return string.Format("[LocalFunctionMethod: ReducedFrom={0}, NumberOfGeneratedParameters={1}, NumberOfCompilerGeneratedGenerics={2}]", ReducedFrom, NumberOfCompilerGeneratedParameters, NumberOfCompilerGeneratedGenerics);
+			return string.Format("[LocalFunctionMethod: ReducedFrom={0}, NumberOfGeneratedParameters={1}, NumberOfCompilerGeneratedTypeParameters={2}]", ReducedFrom, NumberOfCompilerGeneratedParameters, NumberOfCompilerGeneratedTypeParameters);
 		}
 
 		internal int NumberOfCompilerGeneratedParameters { get; }
 
-		internal int NumberOfCompilerGeneratedGenerics { get; set; }
+		internal int NumberOfCompilerGeneratedTypeParameters { get; }
 
 		internal bool IsStaticLocalFunction => NumberOfCompilerGeneratedParameters == 0 && (baseMethod.IsStatic || (baseMethod.DeclaringTypeDefinition.IsCompilerGenerated() && !baseMethod.DeclaringType.GetFields(f => !f.IsStatic).Any()));