Added a separate AwaitResolveResult

ICSharpCode.NRefactory.CSharp/ICSharpCode.NRefactory.CSharp.csproj

@@ -337,6 +337,7 @@
     <Compile Include="Refactoring\TypeSystemAstBuilder.cs" />
     <Compile Include="Refactoring\VariableReferenceGraph.cs" />
     <Compile Include="Resolver\CompositeResolveVisitorNavigator.cs" />
+    <Compile Include="Resolver\AwaitResolveResult.cs" />
     <Compile Include="Resolver\DynamicInvocationResolveResult.cs" />
     <Compile Include="Resolver\DynamicMemberResolveResult.cs" />
     <Compile Include="Resolver\CSharpConversions.cs" />

ICSharpCode.NRefactory.CSharp/Resolver/AwaitResolveResult.cs

@@ -0,0 +1,80 @@
+// Copyright (c) AlphaSierraPapa for the SharpDevelop Team
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of this
+// software and associated documentation files (the "Software"), to deal in the Software
+// without restriction, including without limitation the rights to use, copy, modify, merge,
+// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
+// to whom the Software is furnished to do so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all copies or
+// substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
+// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Linq.Expressions;
+using ICSharpCode.NRefactory.Semantics;
+using ICSharpCode.NRefactory.TypeSystem;
+
+namespace ICSharpCode.NRefactory.CSharp.Resolver
+{
+	/// <summary>
+	/// Represents the result of an await expression.
+	/// </summary>
+	public class AwaitResolveResult : ResolveResult
+	{
+		/// <summary>
+		/// The method representing the GetAwaiter() call. Can be null if the GetAwaiter method was not found.
+		/// </summary>
+		public readonly ResolveResult GetAwaiterInvocation;
+
+		/// <summary>
+		/// Awaiter type. Will not be null (but can be UnknownType).
+		/// </summary>
+		public readonly IType AwaiterType;
+
+		/// <summary>
+		/// Property representing the IsCompleted property on the awaiter type. Can be null if the awaiter type or the property was not found, or when awaiting a dynamic expression.
+		/// </summary>
+		public readonly IProperty IsCompletedProperty;
+
+		/// <summary>
+		/// Method representing the OnCompleted method on the awaiter type. Can be null if the awaiter type or the method was not found, or when awaiting a dynamic expression.
+		/// </summary>
+		public readonly IMethod OnCompletedMethod;
+		
+		/// <summary>
+		/// Method representing the GetResult method on the awaiter type. Can be null if the awaiter type or the method was not found, or when awaiting a dynamic expression.
+		/// </summary>
+		public readonly IMethod GetResultMethod;
+
+		public AwaitResolveResult(IType resultType, ResolveResult getAwaiterInvocation, IType awaiterType, IProperty isCompletedProperty, IMethod onCompletedMethod, IMethod getResultMethod)
+			: base(resultType)
+		{
+			if (awaiterType == null)
+				throw new ArgumentNullException("awaiterType");
+			if (getAwaiterInvocation == null)
+				throw new ArgumentNullException("getAwaiterInvocation");
+			this.GetAwaiterInvocation = getAwaiterInvocation;
+			this.AwaiterType = awaiterType;
+			this.IsCompletedProperty = isCompletedProperty;
+			this.OnCompletedMethod = onCompletedMethod;
+			this.GetResultMethod = getResultMethod;
+		}
+		
+		public override bool IsError {
+			get { return this.GetAwaiterInvocation.IsError || (AwaiterType.Kind != TypeKind.Dynamic && (this.IsCompletedProperty == null || this.OnCompletedMethod == null || this.GetResultMethod == null)); }
+		}
+
+		public override IEnumerable<ResolveResult> GetChildResults() {
+			return new[] { GetAwaiterInvocation };
+		}
+	}
+}

ICSharpCode.NRefactory.CSharp/Resolver/CSharpResolver.cs

@@ -360,8 +360,14 @@ namespace ICSharpCode.NRefactory.CSharp.Resolver
 		#region ResolveUnaryOperator method
 		public ResolveResult ResolveUnaryOperator(UnaryOperatorType op, ResolveResult expression)
 		{
-			if (expression.Type.Kind == TypeKind.Dynamic)
-				return UnaryOperatorResolveResult(SpecialType.Dynamic, op, expression);
+			if (expression.Type.Kind == TypeKind.Dynamic) {
+				if (op == UnaryOperatorType.Await) {
+					return new AwaitResolveResult(SpecialType.Dynamic, new DynamicInvocationResolveResult(new DynamicMemberResolveResult(expression, "GetAwaiter"), DynamicInvocationType.Invocation, EmptyList<ResolveResult>.Instance), SpecialType.Dynamic, null, null, null);
+				}
+				else {
+					return UnaryOperatorResolveResult(SpecialType.Dynamic, op, expression);
+				}
+			}
 			
 			// C# 4.0 spec: §7.3.3 Unary operator overload resolution
 			string overloadableOperatorName = GetOverloadableOperatorName(op);
@@ -375,17 +381,37 @@ namespace ICSharpCode.NRefactory.CSharp.Resolver
 							return ErrorResult;
 					case UnaryOperatorType.AddressOf:
 						return UnaryOperatorResolveResult(new PointerType(expression.Type), op, expression);
-					case UnaryOperatorType.Await:
+					case UnaryOperatorType.Await: {
 						ResolveResult getAwaiterMethodGroup = ResolveMemberAccess(expression, "GetAwaiter", EmptyList<IType>.Instance, NameLookupMode.InvocationTarget);
 						ResolveResult getAwaiterInvocation = ResolveInvocation(getAwaiterMethodGroup, new ResolveResult[0]);
-						var getResultMethodGroup = CreateMemberLookup().Lookup(getAwaiterInvocation, "GetResult", EmptyList<IType>.Instance, true) as MethodGroupResolveResult;
+
+						var lookup = CreateMemberLookup();
+						IMethod getResultMethod;
+						IType awaitResultType;
+						var getResultMethodGroup = lookup.Lookup(getAwaiterInvocation, "GetResult", EmptyList<IType>.Instance, true) as MethodGroupResolveResult;
 						if (getResultMethodGroup != null) {
-							var or = getResultMethodGroup.PerformOverloadResolution(compilation, new ResolveResult[0], allowExtensionMethods: false, conversions: conversions);
-							IType awaitResultType = or.GetBestCandidateWithSubstitutedTypeArguments().ReturnType;
-							return UnaryOperatorResolveResult(awaitResultType, UnaryOperatorType.Await, expression);
-						} else {
-							return UnaryOperatorResolveResult(SpecialType.UnknownType, UnaryOperatorType.Await, expression);
+							var getResultOR = getResultMethodGroup.PerformOverloadResolution(compilation, new ResolveResult[0], allowExtensionMethods: false, conversions: conversions);
+							getResultMethod = getResultOR.FoundApplicableCandidate ? getResultOR.GetBestCandidateWithSubstitutedTypeArguments() as IMethod : null;
+							awaitResultType = getResultMethod != null ? getResultMethod.ReturnType : SpecialType.UnknownType;
+						}
+						else {
+							getResultMethod = null;
+							awaitResultType = SpecialType.UnknownType;
 						}
+
+						var isCompletedRR = lookup.Lookup(getAwaiterInvocation, "IsCompleted", EmptyList<IType>.Instance, false);
+						var isCompletedProperty = (isCompletedRR is MemberResolveResult ? ((MemberResolveResult)isCompletedRR).Member as IProperty : null);
+
+						var onCompletedMethodGroup = lookup.Lookup(getAwaiterInvocation, "OnCompleted", EmptyList<IType>.Instance, true) as MethodGroupResolveResult;
+						IMethod onCompletedMethod = null;
+						if (onCompletedMethodGroup != null) {
+							var onCompletedOR = onCompletedMethodGroup.PerformOverloadResolution(compilation, new ResolveResult[] { new TypeResolveResult(compilation.FindType(new FullTypeName("System.Action")))  }, allowExtensionMethods: false, conversions: conversions);
+							onCompletedMethod = (onCompletedOR.FoundApplicableCandidate ? onCompletedOR.GetBestCandidateWithSubstitutedTypeArguments() as IMethod : null);
+						}
+
+						return new AwaitResolveResult(awaitResultType, getAwaiterInvocation, getAwaiterInvocation.Type, isCompletedProperty, onCompletedMethod, getResultMethod);
+					}
+
 					default:
 						throw new ArgumentException("Invalid value for UnaryOperatorType", "op");
 				}

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

@@ -274,5 +274,371 @@ class Test {
 			Assert.IsFalse(rr.IsError);
 			Assert.AreEqual(unchecked( (ushort)~3 ), rr.ConstantValue);
 		}
+
+		[Test]
+		public void Await() {
+			string program = @"
+using System;
+class MyAwaiter {
+	public bool IsCompleted { get { return false; } }
+	public void OnCompleted(Action continuation) {}
+	public int GetResult() { return 0; }
+}
+class MyAwaitable {
+	public MyAwaiter GetAwaiter() { return null; }
+	public MyAwaiter GetAwaiter(int i) { return null; }
+}
+public class C {
+	public async void M() {
+		MyAwaitable x = null;
+		int i = $await x$;
+	}
+}";
+		
+			var rr = Resolve<AwaitResolveResult>(program);
+			Assert.IsFalse(rr.IsError);
+			Assert.IsTrue(rr.Type.IsKnownType(KnownTypeCode.Int32));
+			Assert.IsInstanceOf<CSharpInvocationResolveResult>(rr.GetAwaiterInvocation);
+			var getAwaiterInvocation = (CSharpInvocationResolveResult)rr.GetAwaiterInvocation;
+			Assert.IsFalse(rr.GetAwaiterInvocation.IsError);
+			Assert.AreEqual(0, getAwaiterInvocation.Arguments.Count);
+			Assert.AreEqual("MyAwaitable.GetAwaiter", getAwaiterInvocation.Member.FullName);
+			Assert.AreEqual(0, getAwaiterInvocation.Member.Parameters.Count);
+
+			Assert.AreEqual("MyAwaiter", rr.AwaiterType.FullName);
+
+			Assert.IsNotNull(rr.IsCompletedProperty);
+			Assert.AreEqual("MyAwaiter.IsCompleted", rr.IsCompletedProperty.FullName);
+
+			Assert.IsNotNull(rr.OnCompletedMethod);
+			Assert.AreEqual("MyAwaiter.OnCompleted", rr.OnCompletedMethod.FullName);
+
+			Assert.IsNotNull(rr.GetResultMethod);
+			Assert.AreEqual("MyAwaiter.GetResult", rr.GetResultMethod.FullName);
+		}
+
+		[Test]
+		public void AwaitWhenGetAwaiterIsAnExtensionMethod() {
+			string program = @"
+using System;
+namespace N {
+	class MyAwaiter {
+		public bool IsCompleted { get { return false; } }
+		public void OnCompleted(Action continuation) {}
+		public int GetResult() { return 0; }
+	}
+	class MyAwaitable {
+	}
+	static class MyAwaitableExtensions {
+		public static MyAwaiter GetAwaiter(this MyAwaitable x) { return null; }
+	}
+	public class C {
+		public async void M() {
+			MyAwaitable x = null;
+			int i = $await x$;
+		}
+	}
+}";
+		
+			var rr = Resolve<AwaitResolveResult>(program);
+			Assert.IsFalse(rr.IsError);
+			Assert.IsTrue(rr.Type.IsKnownType(KnownTypeCode.Int32));
+			Assert.IsInstanceOf<CSharpInvocationResolveResult>(rr.GetAwaiterInvocation);
+			var getAwaiterInvocation = (CSharpInvocationResolveResult)rr.GetAwaiterInvocation;
+			Assert.IsFalse(rr.GetAwaiterInvocation.IsError);
+			Assert.AreEqual(1, getAwaiterInvocation.Arguments.Count);
+			Assert.AreEqual("N.MyAwaitableExtensions.GetAwaiter", getAwaiterInvocation.Member.FullName);
+			Assert.AreEqual(1, getAwaiterInvocation.Member.Parameters.Count);
+			Assert.IsTrue(getAwaiterInvocation.Arguments[0] is LocalResolveResult && ((LocalResolveResult)getAwaiterInvocation.Arguments[0]).Variable.Name == "x");
+
+			Assert.AreEqual("N.MyAwaiter", rr.AwaiterType.FullName);
+
+			Assert.IsNotNull(rr.IsCompletedProperty);
+			Assert.AreEqual("N.MyAwaiter.IsCompleted", rr.IsCompletedProperty.FullName);
+
+			Assert.IsNotNull(rr.OnCompletedMethod);
+			Assert.AreEqual("N.MyAwaiter.OnCompleted", rr.OnCompletedMethod.FullName);
+
+			Assert.IsNotNull(rr.GetResultMethod);
+			Assert.AreEqual("N.MyAwaiter.GetResult", rr.GetResultMethod.FullName);
+		}
+
+		[Test, Ignore("TODO: MS C# (at least the RC version) refuses to use default values in GetAwaiter(). I do not know, however, if this is by design, and I could not find a simple, nice way to do the implementation")]
+		public void GetAwaiterMethodWithDefaultArgumentCannotBeUsed() {
+			string program = @"
+using System;
+class MyAwaiter {
+	public bool IsCompleted { get { return false; } }
+	public void OnCompleted(Action continuation) {}
+	public int GetResult() { return 0; }
+}
+class MyAwaitable {
+	public MyAwaiter GetAwaiter(int i = 0) { return null; }
+}
+public class C {
+	public async void M() {
+		MyAwaitable x = null;
+		int i = $await x$;
+	}
+}";
+		
+			var rr = Resolve<AwaitResolveResult>(program);
+			Assert.IsFalse(rr.IsError);
+			Assert.AreEqual(SpecialType.UnknownType, rr.Type);
+			Assert.IsInstanceOf<CSharpInvocationResolveResult>(rr.GetAwaiterInvocation);
+			Assert.IsTrue(rr.GetAwaiterInvocation.IsError);
+
+			Assert.AreEqual(rr.AwaiterType, SpecialType.UnknownType);
+
+			Assert.IsNull(rr.IsCompletedProperty);
+			Assert.IsNull(rr.OnCompletedMethod);
+			Assert.IsNull(rr.GetResultMethod);
+		}
+
+		[Test, Ignore("TODO: MS C# (at least the RC version) refuses to use default values in GetAwaiter(). I do not know, however, if this is by design, and I could not find a simple, nice way to do the implementation")]
+		public void GetAwaiterMethodWithDefaultArgumentHidesExtensionMethodAndResultsInError() {
+			string program = @"
+using System;
+namespace N {
+	class MyAwaiter {
+		public bool IsCompleted { get { return false; } }
+		public void OnCompleted(Action continuation) {}
+		public int GetResult() { return 0; }
+	}
+	class MyAwaitable {
+		public MyAwaiter GetAwaiter(int i = 0) { return null; }
+	}
+	static class MyAwaitableExtensions {
+		public static MyAwaiter GetAwaiter(this MyAwaitable x) { return null; }
+	}
+	public class C {
+		public async void M() {
+			MyAwaitable x = null;
+			int i = $await x$;
+		}
+	}
+}";
+		
+			var rr = Resolve<AwaitResolveResult>(program);
+			Assert.IsFalse(rr.IsError);
+			Assert.AreEqual(SpecialType.UnknownType, rr.Type);
+			Assert.IsInstanceOf<CSharpInvocationResolveResult>(rr.GetAwaiterInvocation);
+			Assert.IsTrue(rr.GetAwaiterInvocation.IsError);
+
+			Assert.AreEqual(rr.AwaiterType, SpecialType.UnknownType);
+
+			Assert.IsNull(rr.IsCompletedProperty);
+			Assert.IsNull(rr.OnCompletedMethod);
+			Assert.IsNull(rr.GetResultMethod);
+		}
+
+		[Test]
+		public void GetAwaiterMethodWithArgumentDoesNotHideExtensionMethod() {
+			string program = @"
+using System;
+namespace N {
+	class MyAwaiter {
+		public bool IsCompleted { get { return false; } }
+		public void OnCompleted(Action continuation) {}
+		public int GetResult() { return 0; }
+	}
+	class MyAwaitable {
+		public static MyAwaiter GetAwaiter(int i) { return null; }
+	}
+	static class MyAwaitableExtensions {
+		public static MyAwaiter GetAwaiter(this MyAwaitable x) { return null; }
+	}
+	public class C {
+		public async void M() {
+			MyAwaitable x = null;
+			int i = $await x$;
+		}
+	}
+}";
+		
+			var rr = Resolve<AwaitResolveResult>(program);
+			Assert.IsFalse(rr.IsError);
+			Assert.IsTrue(rr.Type.IsKnownType(KnownTypeCode.Int32));
+			Assert.IsInstanceOf<CSharpInvocationResolveResult>(rr.GetAwaiterInvocation);
+			var getAwaiterInvocation = (CSharpInvocationResolveResult)rr.GetAwaiterInvocation;
+			Assert.IsFalse(rr.GetAwaiterInvocation.IsError);
+			Assert.AreEqual(1, getAwaiterInvocation.Arguments.Count);
+			Assert.AreEqual("N.MyAwaitableExtensions.GetAwaiter", getAwaiterInvocation.Member.FullName);
+			Assert.AreEqual(1, getAwaiterInvocation.Member.Parameters.Count);
+			Assert.IsTrue(getAwaiterInvocation.Arguments[0] is LocalResolveResult && ((LocalResolveResult)getAwaiterInvocation.Arguments[0]).Variable.Name == "x");
+
+			Assert.AreEqual("N.MyAwaiter", rr.AwaiterType.FullName);
+
+			Assert.IsNotNull(rr.IsCompletedProperty);
+			Assert.AreEqual("N.MyAwaiter.IsCompleted", rr.IsCompletedProperty.FullName);
+
+			Assert.IsNotNull(rr.OnCompletedMethod);
+			Assert.AreEqual("N.MyAwaiter.OnCompleted", rr.OnCompletedMethod.FullName);
+
+			Assert.IsNotNull(rr.GetResultMethod);
+			Assert.AreEqual("N.MyAwaiter.GetResult", rr.GetResultMethod.FullName);
+		}
+
+		[Test]
+		public void AwaiterWithNoSuitableGetResult() {
+			string program = @"
+using System;
+namespace N {
+	class MyAwaiter {
+		public bool IsCompleted { get { return false; } }
+		public void OnCompleted(Action continuation) {}
+		public int GetResult(int i) { return 0; }
+	}
+	class MyAwaitable {
+		public static MyAwaiter GetAwaiter(int i) { return null; }
+	}
+	static class MyAwaitableExtensions {
+		public static MyAwaiter GetAwaiter(this MyAwaitable x) { return null; }
+	}
+	public class C {
+		public async void M() {
+			MyAwaitable x = null;
+			int i = $await x$;
+		}
+	}
+}";
+		
+			var rr = Resolve<AwaitResolveResult>(program);
+			Assert.IsTrue(rr.IsError);
+			Assert.AreEqual(SpecialType.UnknownType, rr.Type);
+			Assert.IsInstanceOf<CSharpInvocationResolveResult>(rr.GetAwaiterInvocation);
+			var getAwaiterInvocation = (CSharpInvocationResolveResult)rr.GetAwaiterInvocation;
+			Assert.IsFalse(rr.GetAwaiterInvocation.IsError);
+			Assert.AreEqual(1, getAwaiterInvocation.Arguments.Count);
+			Assert.AreEqual("N.MyAwaitableExtensions.GetAwaiter", getAwaiterInvocation.Member.FullName);
+			Assert.AreEqual(1, getAwaiterInvocation.Member.Parameters.Count);
+			Assert.IsTrue(getAwaiterInvocation.Arguments[0] is LocalResolveResult && ((LocalResolveResult)getAwaiterInvocation.Arguments[0]).Variable.Name == "x");
+
+			Assert.AreEqual("N.MyAwaiter", rr.AwaiterType.FullName);
+
+			Assert.IsNotNull(rr.IsCompletedProperty);
+			Assert.AreEqual("N.MyAwaiter.IsCompleted", rr.IsCompletedProperty.FullName);
+
+			Assert.IsNotNull(rr.OnCompletedMethod);
+			Assert.AreEqual("N.MyAwaiter.OnCompleted", rr.OnCompletedMethod.FullName);
+
+			Assert.IsNull(rr.GetResultMethod);
+		}
+
+		[Test]
+		public void AwaiterWithNoIsCompletedProperty() {
+			string program = @"
+using System;
+namespace N {
+	class MyAwaiter {
+		public bool IsCompleted() { return false; }
+		public void OnCompleted(Action continuation) {}
+		public int GetResult(int i) { return 0; }
+	}
+	class MyAwaitable {
+		public static MyAwaiter GetAwaiter(int i) { return null; }
+	}
+	static class MyAwaitableExtensions {
+		public static MyAwaiter GetAwaiter(this MyAwaitable x) { return null; }
+	}
+	public class C {
+		public async void M() {
+			MyAwaitable x = null;
+			int i = $await x$;
+		}
+	}
+}";
+		
+			var rr = Resolve<AwaitResolveResult>(program);
+			Assert.IsTrue(rr.IsError);
+			Assert.AreEqual(SpecialType.UnknownType, rr.Type);
+			Assert.IsInstanceOf<CSharpInvocationResolveResult>(rr.GetAwaiterInvocation);
+			var getAwaiterInvocation = (CSharpInvocationResolveResult)rr.GetAwaiterInvocation;
+			Assert.IsFalse(rr.GetAwaiterInvocation.IsError);
+			Assert.AreEqual(1, getAwaiterInvocation.Arguments.Count);
+			Assert.AreEqual("N.MyAwaitableExtensions.GetAwaiter", getAwaiterInvocation.Member.FullName);
+			Assert.AreEqual(1, getAwaiterInvocation.Member.Parameters.Count);
+			Assert.IsTrue(getAwaiterInvocation.Arguments[0] is LocalResolveResult && ((LocalResolveResult)getAwaiterInvocation.Arguments[0]).Variable.Name == "x");
+
+			Assert.AreEqual("N.MyAwaiter", rr.AwaiterType.FullName);
+
+			Assert.IsNull(rr.IsCompletedProperty);
+
+			Assert.IsNotNull(rr.OnCompletedMethod);
+			Assert.AreEqual("N.MyAwaiter.OnCompleted", rr.OnCompletedMethod.FullName);
+
+			Assert.IsNull(rr.GetResultMethod);
+		}
+
+		[Test]
+		public void AwaiterWithNoOnCompletedMethodWithSuitableSignature() {
+			string program = @"
+using System;
+class MyAwaiter {
+	public bool IsCompleted { get { return false; } }
+	public void OnCompleted(Func<int> continuation) {}
+	public int GetResult() { return 0; }
+}
+class MyAwaitable {
+	public MyAwaiter GetAwaiter() { return null; }
+	public MyAwaiter GetAwaiter(int i) { return null; }
+}
+public class C {
+	public async void M() {
+		MyAwaitable x = null;
+		int i = $await x$;
+	}
+}";
+		
+			var rr = Resolve<AwaitResolveResult>(program);
+			Assert.IsTrue(rr.IsError);
+			Assert.IsTrue(rr.Type.IsKnownType(KnownTypeCode.Int32));
+			Assert.IsInstanceOf<CSharpInvocationResolveResult>(rr.GetAwaiterInvocation);
+			var getAwaiterInvocation = (CSharpInvocationResolveResult)rr.GetAwaiterInvocation;
+			Assert.IsFalse(rr.GetAwaiterInvocation.IsError);
+			Assert.AreEqual(0, getAwaiterInvocation.Arguments.Count);
+			Assert.AreEqual("MyAwaitable.GetAwaiter", getAwaiterInvocation.Member.FullName);
+			Assert.AreEqual(0, getAwaiterInvocation.Member.Parameters.Count);
+
+			Assert.AreEqual("MyAwaiter", rr.AwaiterType.FullName);
+
+			Assert.IsNotNull(rr.IsCompletedProperty);
+			Assert.AreEqual("MyAwaiter.IsCompleted", rr.IsCompletedProperty.FullName);
+
+			Assert.IsNull(rr.OnCompletedMethod);
+
+			Assert.IsNotNull(rr.GetResultMethod);
+			Assert.AreEqual("MyAwaiter.GetResult", rr.GetResultMethod.FullName);
+		}
+
+		[Test]
+		public void AwaitDynamic() {
+			string program = @"
+public class C {
+	public async void M() {
+		dynamic x = null;
+		int i = $await x$;
+	}
+}";
+		
+			var rr = Resolve<AwaitResolveResult>(program);
+			Assert.IsFalse(rr.IsError);
+			Assert.AreEqual(SpecialType.Dynamic, rr.Type);
+			Assert.IsInstanceOf<DynamicInvocationResolveResult>(rr.GetAwaiterInvocation);
+			var getAwaiterInvocation = (DynamicInvocationResolveResult)rr.GetAwaiterInvocation;
+			Assert.IsFalse(rr.GetAwaiterInvocation.IsError);
+			Assert.AreEqual(DynamicInvocationType.Invocation, getAwaiterInvocation.InvocationType);
+			Assert.AreEqual(0, getAwaiterInvocation.Arguments.Count);
+			Assert.IsInstanceOf<DynamicMemberResolveResult>(getAwaiterInvocation.Target);
+			var target = (DynamicMemberResolveResult)getAwaiterInvocation.Target;
+			Assert.IsInstanceOf<LocalResolveResult>(target.Target);
+			Assert.AreEqual("GetAwaiter", target.Member);
+
+			Assert.AreEqual(SpecialType.Dynamic, rr.AwaiterType);
+
+			Assert.IsNull(rr.IsCompletedProperty);
+			Assert.IsNull(rr.OnCompletedMethod);
+			Assert.IsNull(rr.GetResultMethod);
+		}
 	}
 }