Implement support for explicit interface implementation of operators and operator uses.

ICSharpCode.Decompiler.Tests/TestCases/Pretty/StaticAbstractInterfaceMembers.cs

@@ -2,11 +2,59 @@
 
 namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty.StaticAbstractInterfaceMembers
 {
+	internal class C : I<C>
+	{
+		private string _s;
+
+		static C I<C>.P { get; set; }
+		static event Action I<C>.E {
+			add {
+
+			}
+			remove {
+
+			}
+		}
+		public C(string s)
+		{
+			_s = s;
+		}
+
+		static void I<C>.M(object x)
+		{
+			Console.WriteLine("Implementation");
+		}
+		static C I<C>.operator +(C l, C r)
+		{
+			return new C(l._s + " " + r._s);
+		}
+
+		static bool I<C>.operator ==(C l, C r)
+		{
+			return l._s == r._s;
+		}
+
+		static bool I<C>.operator !=(C l, C r)
+		{
+			return l._s != r._s;
+		}
+
+		static implicit I<C>.operator C(string s)
+		{
+			return new C(s);
+		}
+
+		static explicit I<C>.operator string(C c)
+		{
+			return c._s;
+		}
+	}
+
 	internal interface I<T> where T : I<T>
 	{
 		static abstract T P { get; set; }
 		static abstract event Action E;
-		static abstract void M();
+		static abstract void M(object x);
 		static abstract T operator +(T l, T r);
 		static abstract bool operator ==(T l, T r);
 		static abstract bool operator !=(T l, T r);
@@ -25,28 +73,77 @@ namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty.StaticAbstractInterfaceM
 
 	internal interface IAmStatic<T> where T : IAmStatic<T>
 	{
+		static int f;
 		static T P { get; set; }
 		static event Action E;
-		static void M()
+		static void M(object x)
 		{
 		}
-		static T operator +(IAmStatic<T> l, T r)
+		static IAmStatic<T> operator +(IAmStatic<T> l, IAmStatic<T> r)
 		{
 			throw new NotImplementedException();
 		}
+		static IAmStatic()
+		{
+			f = 42;
+		}
 	}
 
 	internal interface IAmVirtual<T> where T : IAmVirtual<T>
 	{
 		static virtual T P { get; set; }
 		static virtual event Action E;
-		static virtual void M()
+		static virtual void M(object x)
 		{
 		}
 		static virtual T operator +(T l, T r)
 		{
 			throw new NotImplementedException();
 		}
+		static virtual implicit operator T(string s)
+		{
+			return default(T);
+		}
+		static virtual explicit operator string(T t)
+		{
+			return null;
+		}
+	}
+
+	internal class Uses
+	{
+		public static T TestVirtualStaticUse<T>(T a, T b) where T : IAmVirtual<T>
+		{
+			T.P = a;
+			a = "World";
+			T.E += null;
+			T.E -= null;
+			T.M("Hello");
+			UseString((string)b);
+			return a + b;
+		}
+		public static IAmStatic<T> TestStaticUse<T>(T a, T b) where T : IAmStatic<T>
+		{
+			IAmStatic<T>.f = 11;
+			IAmStatic<T>.P = a;
+			IAmStatic<T>.E += null;
+			IAmStatic<T>.E -= null;
+			IAmStatic<T>.M("Hello");
+			return a + b;
+		}
+		public static I<T> TestAbstractStaticUse<T>(T a, T b) where T : I<T>
+		{
+			T.P = a;
+			a = "World";
+			T.E += null;
+			T.E -= null;
+			T.M("Hello");
+			UseString((string)b);
+			return a + b;
+		}
+		private static void UseString(string a)
+		{
+		}
 	}
 
 	public class X : IAmSimple

ICSharpCode.Decompiler/CSharp/CSharpDecompiler.cs

@@ -1585,7 +1585,7 @@ namespace ICSharpCode.Decompiler.CSharp
 				var typeSystemAstBuilder = CreateAstBuilder(decompileRun.Settings);
 				var methodDecl = typeSystemAstBuilder.ConvertEntity(method);
 				int lastDot = method.Name.LastIndexOf('.');
-				if (method.IsExplicitInterfaceImplementation && lastDot >= 0)
+				if (methodDecl is not OperatorDeclaration && method.IsExplicitInterfaceImplementation && lastDot >= 0)
 				{
 					methodDecl.Name = method.Name.Substring(lastDot + 1);
 				}

ICSharpCode.Decompiler/CSharp/OutputVisitor/CSharpOutputVisitor.cs

@@ -2574,6 +2574,8 @@ namespace ICSharpCode.Decompiler.CSharp.OutputVisitor
 			{
 				operatorDeclaration.ReturnType.AcceptVisitor(this);
 			}
+			Space();
+			WritePrivateImplementationType(operatorDeclaration.PrivateImplementationType);
 			WriteKeyword(OperatorDeclaration.OperatorKeywordRole);
 			Space();
 			if (OperatorDeclaration.IsChecked(operatorDeclaration.OperatorType))

ICSharpCode.Decompiler/CSharp/Syntax/TypeMembers/OperatorDeclaration.cs

@@ -159,6 +159,15 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 			get { return SymbolKind.Operator; }
 		}
 
+		/// <summary>
+		/// Gets/Sets the type reference of the interface that is explicitly implemented.
+		/// Null node if this member is not an explicit interface implementation.
+		/// </summary>
+		public AstType PrivateImplementationType {
+			get { return GetChildByRole(PrivateImplementationTypeRole); }
+			set { SetChildByRole(PrivateImplementationTypeRole, value); }
+		}
+
 		OperatorType operatorType;
 
 		public OperatorType OperatorType {
@@ -347,7 +356,9 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 		protected internal override bool DoMatch(AstNode other, PatternMatching.Match match)
 		{
 			OperatorDeclaration o = other as OperatorDeclaration;
-			return o != null && this.MatchAttributesAndModifiers(o, match) && this.OperatorType == o.OperatorType
+			return o != null && this.MatchAttributesAndModifiers(o, match)
+				&& this.PrivateImplementationType.DoMatch(o.PrivateImplementationType, match)
+				&& this.OperatorType == o.OperatorType
 				&& this.ReturnType.DoMatch(o.ReturnType, match)
 				&& this.Parameters.DoMatch(o.Parameters, match) && this.Body.DoMatch(o.Body, match);
 		}

ICSharpCode.Decompiler/CSharp/Syntax/TypeSystemAstBuilder.cs

@@ -1740,6 +1740,10 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 				case SymbolKind.Event:
 					return ConvertEvent((IEvent)entity);
 				case SymbolKind.Method:
+					if (entity.Name.Contains(".op_"))
+					{
+						goto case SymbolKind.Operator;
+					}
 					return ConvertMethod((IMethod)entity);
 				case SymbolKind.Operator:
 					return ConvertOperator((IMethod)entity);
@@ -2225,7 +2229,9 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 
 		EntityDeclaration ConvertOperator(IMethod op)
 		{
-			OperatorType? opType = OperatorDeclaration.GetOperatorType(op.Name);
+			int dot = op.Name.LastIndexOf('.');
+			string name = op.Name.Substring(dot + 1);
+			OperatorType? opType = OperatorDeclaration.GetOperatorType(name);
 			if (opType == null)
 				return ConvertMethod(op);
 			if (opType == OperatorType.UnsignedRightShift && !SupportUnsignedRightShift)
@@ -2255,6 +2261,7 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 				decl.AddAnnotation(new MemberResolveResult(null, op));
 			}
 			decl.Body = GenerateBodyBlock();
+			decl.PrivateImplementationType = GetExplicitInterfaceType(op);
 			return decl;
 		}
 

ICSharpCode.Decompiler/TypeSystem/Implementation/AbstractTypeParameter.cs

@@ -378,10 +378,8 @@ namespace ICSharpCode.Decompiler.TypeSystem.Implementation
 
 		static Predicate<T> FilterNonStatic<T>(Predicate<T> filter) where T : class, IMember
 		{
-			if (filter == null)
+			return member => (!member.IsStatic || member.SymbolKind == SymbolKind.Operator || member.IsVirtual)
-				return member => !member.IsStatic;
+				&& (filter == null || filter(member));
-			else
-				return member => !member.IsStatic && filter(member);
 		}
 
 		public sealed override bool Equals(object obj)