Rename IsExtensionMethodGroupConversion -> DelegateCapturesFirstArgument.

ICSharpCode.NRefactory.CSharp/Resolver/CSharpConversions.cs

@@ -1062,10 +1062,11 @@ namespace ICSharpCode.NRefactory.CSharp.Resolver
 				var thisRR = rr.TargetResult as ThisResolveResult;
 				bool isVirtual = method.IsOverridable && !(thisRR != null && thisRR.CausesNonVirtualInvocation);
 				bool isValid = !or.IsAmbiguous && IsDelegateCompatible(method, invoke, or.IsExtensionMethodInvocation);
+				bool delegateCapturesFirstArgument = or.IsExtensionMethodInvocation || !method.IsStatic;
 				if (isValid)
-					return Conversion.MethodGroupConversion(method, isVirtual, or.IsExtensionMethodInvocation);
+					return Conversion.MethodGroupConversion(method, isVirtual, delegateCapturesFirstArgument);
 				else
-					return Conversion.InvalidMethodGroupConversion(method, isVirtual, or.IsExtensionMethodInvocation);
+					return Conversion.InvalidMethodGroupConversion(method, isVirtual, delegateCapturesFirstArgument);
 			} else {
 				return Conversion.None;
 			}

ICSharpCode.NRefactory.Tests/CSharp/Resolver/ConversionsTest.cs

@@ -615,6 +615,25 @@ class Test {
 			var c = GetConversion(program);
 			Assert.IsTrue(c.IsValid);
 			Assert.IsTrue(c.IsMethodGroupConversion);
+			Assert.IsFalse(c.DelegateCapturesFirstArgument);
+			Assert.IsNotNull(c.Method);
+		}
+		
+		[Test]
+		public void MethodGroupConversion_Void_InstanceMethod()
+		{
+			string program = @"using System;
+delegate void D();
+class Test {
+	D d;
+	public void M() {
+		d = $M$;
+	}
+}";
+			var c = GetConversion(program);
+			Assert.IsTrue(c.IsValid);
+			Assert.IsTrue(c.IsMethodGroupConversion);
+			Assert.IsTrue(c.DelegateCapturesFirstArgument);
 			Assert.IsNotNull(c.Method);
 		}
 		
@@ -837,7 +856,7 @@ class Test {
 		{
 			string program = @"using System;
 static class Ext {
-	public void M(this string s, int x) {}
+	public static void M(this string s, int x) {}
 }
 class Test {
 	delegate void D(int a);
@@ -849,7 +868,7 @@ class Test {
 			var c = GetConversion(program);
 			Assert.IsTrue(c.IsValid);
 			Assert.IsTrue(c.IsMethodGroupConversion);
-			Assert.IsTrue(c.IsExtensionMethodGroupConversion);
+			Assert.IsTrue(c.DelegateCapturesFirstArgument);
 		}
 
 		[Test]
@@ -857,7 +876,7 @@ class Test {
 		{
 			string program = @"using System;
 static class Ext {
-	public void M(this string s, int x) {}
+	public static void M(this string s, int x) {}
 }
 class Test {
 	delegate void D(string s, int a);
@@ -868,7 +887,7 @@ class Test {
 			var c = GetConversion(program);
 			Assert.IsTrue(c.IsValid);
 			Assert.IsTrue(c.IsMethodGroupConversion);
-			Assert.IsFalse(c.IsExtensionMethodGroupConversion);
+			Assert.IsFalse(c.DelegateCapturesFirstArgument);
 		}
 
 		[Test]

ICSharpCode.NRefactory/Semantics/Conversion.cs

@@ -97,18 +97,18 @@ namespace ICSharpCode.NRefactory.Semantics
 			return new UserDefinedConv(isImplicit, operatorMethod, conversionBeforeUserDefinedOperator, conversionAfterUserDefinedOperator, isLifted, isAmbiguous);
 		}
 		
-		public static Conversion MethodGroupConversion(IMethod chosenMethod, bool isVirtualMethodLookup, bool isExtensionMethodGroupConversion)
+		public static Conversion MethodGroupConversion(IMethod chosenMethod, bool isVirtualMethodLookup, bool delegateCapturesFirstArgument)
 		{
 			if (chosenMethod == null)
 				throw new ArgumentNullException("chosenMethod");
-			return new MethodGroupConv(chosenMethod, isVirtualMethodLookup, isExtensionMethodGroupConversion, isValid: true);
+			return new MethodGroupConv(chosenMethod, isVirtualMethodLookup, delegateCapturesFirstArgument, isValid: true);
 		}
 		
-		public static Conversion InvalidMethodGroupConversion(IMethod chosenMethod, bool isVirtualMethodLookup, bool isExtensionMethodGroupConversion)
+		public static Conversion InvalidMethodGroupConversion(IMethod chosenMethod, bool isVirtualMethodLookup, bool delegateCapturesFirstArgument)
 		{
 			if (chosenMethod == null)
 				throw new ArgumentNullException("chosenMethod");
-			return new MethodGroupConv(chosenMethod, isVirtualMethodLookup, isExtensionMethodGroupConversion, isValid: false);
+			return new MethodGroupConv(chosenMethod, isVirtualMethodLookup, delegateCapturesFirstArgument, isValid: false);
 		}
 		#endregion
 		
@@ -346,14 +346,14 @@ namespace ICSharpCode.NRefactory.Semantics
 		{
 			readonly IMethod method;
 			readonly bool isVirtualMethodLookup;
-			readonly bool isExtensionMethodGroupConversion;
+			readonly bool delegateCapturesFirstArgument;
 			readonly bool isValid;
 			
-			public MethodGroupConv(IMethod method, bool isVirtualMethodLookup, bool isExtensionMethodGroupConversion, bool isValid)
+			public MethodGroupConv(IMethod method, bool isVirtualMethodLookup, bool delegateCapturesFirstArgument, bool isValid)
 			{
 				this.method = method;
 				this.isVirtualMethodLookup = isVirtualMethodLookup;
-				this.isExtensionMethodGroupConversion = isExtensionMethodGroupConversion;
+				this.delegateCapturesFirstArgument = delegateCapturesFirstArgument;
 				this.isValid = isValid;
 			}
 			
@@ -373,8 +373,8 @@ namespace ICSharpCode.NRefactory.Semantics
 				get { return isVirtualMethodLookup; }
 			}
 			
-			public override bool IsExtensionMethodGroupConversion {
-				get { return isExtensionMethodGroupConversion; }
+			public override bool DelegateCapturesFirstArgument {
+				get { return delegateCapturesFirstArgument; }
 			}
 
 			public override IMethod Method {
@@ -525,9 +525,12 @@ namespace ICSharpCode.NRefactory.Semantics
 		}
 		
 		/// <summary>
-		/// For method-group conversions, gets whether the conversion is a method group conversion of an extension method performed on an instance (eg. Func&lt;int&gt; f = myEnumerable.Single).
+		/// For method-group conversions, gets whether the conversion captures the first argument.
+		/// 
+		/// For instance methods, this property always returns true for C# method-group conversions.
+		/// For static methods, this property returns true for method-group conversions of an extension method performed on an instance (eg. <c>Func&lt;int&gt; f = myEnumerable.Single</c>).
 		/// </summary>
-		public virtual bool IsExtensionMethodGroupConversion {
+		public virtual bool DelegateCapturesFirstArgument {
 			get { return false; }
 		}