Empty Display string, test for use-site errors, Visit throws

dotnet · Jun 13, 2016 · 3496abb · 3496abb
1 parent bc3bd43
commit 3496abb
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Showing 3 changed files with 46 additions and 4 deletions.
diff --git a/src/Compilers/CSharp/Portable/BoundTree/Formatting.cs b/src/Compilers/CSharp/Portable/BoundTree/Formatting.cs
@@ -80,10 +80,7 @@ internal partial class OutDeconstructVarPendingInference
     {
         public override object Display
         {
-            get
-            {
-                return MessageID.IDS_FeatureTuples.Localize();
-            }
+            get { return string.Empty; }
         }
     }
 }
diff --git a/src/Compilers/CSharp/Portable/FlowAnalysis/DataFlowPass.cs b/src/Compilers/CSharp/Portable/FlowAnalysis/DataFlowPass.cs
@@ -1735,6 +1735,12 @@ public override BoundNode VisitDeconstructionAssignmentOperator(BoundDeconstruct
             return null;
         }
 
+        public override BoundNode VisitOutDeconstructVarPendingInference(OutDeconstructVarPendingInference node)
+        {
+            // OutDeconstructVarPendingInference nodes are only used within initial binding, but don't survive past that stage
+            throw ExceptionUtilities.Unreachable;
+        }
+
         public override BoundNode VisitIncrementOperator(BoundIncrementOperator node)
         {
             base.VisitIncrementOperator(node);

diff --git a/src/Compilers/CSharp/Test/Emit/CodeGen/CodeGenDeconstructTests.cs b/src/Compilers/CSharp/Test/Emit/CodeGen/CodeGenDeconstructTests.cs
@@ -2091,6 +2091,45 @@ class C1
                 );
         }
 
+        [Fact]
+        public void DeconstructHasUseSiteError()
+        {
+            string libMissingSource = @"public class Missing { }";
+
+            string libSource = @"
+public class C
+{
+    public void Deconstruct(out Missing a, out Missing b) { a = new Missing(); b = new Missing(); }
+}
+";
+
+            string source = @"
+class C1
+{
+    static void Main()
+    {
+        object x, y;
+        (x, y) = new C();
+    }
+}
+";
+            var libMissingComp = CreateCompilationWithMscorlib(new string[] { libMissingSource }, assemblyName: "libMissingComp").VerifyDiagnostics();
+            var libMissingRef = libMissingComp.EmitToImageReference();
+
+            var libComp = CreateCompilationWithMscorlib(new string[] { libSource }, references: new[] { libMissingRef }, parseOptions: TestOptions.Regular.WithTuplesFeature()).VerifyDiagnostics();
+            var libRef = libComp.EmitToImageReference();
+
+            var comp = CreateCompilationWithMscorlib(new string[] { source }, references: new[] { libRef }, parseOptions: TestOptions.Regular.WithTuplesFeature());
+            comp.VerifyDiagnostics(
+                // (7,18): error CS0012: The type 'Missing' is defined in an assembly that is not referenced. You must add a reference to assembly 'libMissingComp, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null'.
+                //         (x, y) = new C();
+                Diagnostic(ErrorCode.ERR_NoTypeDef, "new C()").WithArguments("Missing", "libMissingComp, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null").WithLocation(7, 18),
+                // (7,18): error CS8206: No Deconstruct instance or extension method was found for type 'C', with 2 out parameters.
+                //         (x, y) = new C();
+                Diagnostic(ErrorCode.ERR_MissingDeconstruct, "new C()").WithArguments("C", "2").WithLocation(7, 18)
+                );
+        }
+
         [Fact]
         public void StaticDeconstruct()
         {