IsImplicitlyDeclared in tuple fields.

src/Compilers/CSharp/Portable/Symbols/Tuples/TupleErrorFieldSymbol.cs

@@ -26,7 +26,11 @@ internal sealed class TupleErrorFieldSymbol : SynthesizedFieldSymbolBase
         private readonly ImmutableArray<Location> _locations;
         private readonly DiagnosticInfo _useSiteDiagnosticInfo;
 
-        public TupleErrorFieldSymbol(NamedTypeSymbol container, string name, int tupleElementIndex, Location location, TypeSymbol type, DiagnosticInfo useSiteDiagnosticInfo)
+        // default tuple elements like Item1 or Item20 could be provided by the user or
+        // otherwise implicitly declared by compiler
+        private readonly bool _isImplicitlyDeclared;
+
+        public TupleErrorFieldSymbol(NamedTypeSymbol container, string name, int tupleElementIndex, Location location, TypeSymbol type, DiagnosticInfo useSiteDiagnosticInfo, bool isImplicitlyDeclared)
             : base(container, name, isPublic:true, isReadOnly:false, isStatic:false)
         {
             Debug.Assert(name != null);
@@ -34,6 +38,7 @@ public TupleErrorFieldSymbol(NamedTypeSymbol container, string name, int tupleEl
             _locations = location == null ? ImmutableArray<Location>.Empty : ImmutableArray.Create(location);
             _useSiteDiagnosticInfo = useSiteDiagnosticInfo;
             _tupleElementIndex = tupleElementIndex;
+            _isImplicitlyDeclared = isImplicitlyDeclared;
         }
 
         public override bool IsTupleField
@@ -92,7 +97,9 @@ public override ImmutableArray<SyntaxReference> DeclaringSyntaxReferences
         {
             get
             {
-                return GetDeclaringSyntaxReferenceHelper<CSharpSyntaxNode>(_locations);
+                return _isImplicitlyDeclared ?
+                    ImmutableArray<SyntaxReference>.Empty :
+                    GetDeclaringSyntaxReferenceHelper<CSharpSyntaxNode>(_locations);
             }
         }
 
@@ -100,7 +107,7 @@ public override bool IsImplicitlyDeclared
         {
             get
             {
-                return false;
+                return _isImplicitlyDeclared;
             }
         }
 

src/Compilers/CSharp/Portable/Symbols/Tuples/TupleFieldSymbol.cs

@@ -147,10 +147,15 @@ internal class TupleElementFieldSymbol : TupleFieldSymbol
     {
         private readonly ImmutableArray<Location> _locations;
 
-        public TupleElementFieldSymbol(TupleTypeSymbol container, FieldSymbol underlyingField, int tupleElementIndex, Location location)
+        // default tuple elements like Item1 or Item20 could be provided by the user or
+        // otherwise implicitly declared by compiler
+        private readonly bool _isImplicitlyDeclared;
+
+        public TupleElementFieldSymbol(TupleTypeSymbol container, FieldSymbol underlyingField, int tupleElementIndex, Location location, bool isImplicitlyDeclared)
             : base(container, underlyingField, tupleElementIndex)
         {
             _locations = location == null ? ImmutableArray<Location>.Empty : ImmutableArray.Create(location);
+            _isImplicitlyDeclared = isImplicitlyDeclared;
         }
 
         public override ImmutableArray<Location> Locations
@@ -165,7 +170,9 @@ public override ImmutableArray<SyntaxReference> DeclaringSyntaxReferences
         {
             get
             {
-                return GetDeclaringSyntaxReferenceHelper<CSharpSyntaxNode>(_locations);
+                return _isImplicitlyDeclared ? 
+                    ImmutableArray<SyntaxReference>.Empty : 
+                    GetDeclaringSyntaxReferenceHelper<CSharpSyntaxNode>(_locations);
             }
         }
 
@@ -173,7 +180,7 @@ public override bool IsImplicitlyDeclared
         {
             get
             {
-                return false;
+                return _isImplicitlyDeclared;
             }
         }
 
@@ -223,8 +230,8 @@ internal sealed class TupleVirtualElementFieldSymbol : TupleElementFieldSymbol
     {
         private readonly string _name;
 
-        public TupleVirtualElementFieldSymbol(TupleTypeSymbol container, FieldSymbol underlyingField, string name, int tupleElementIndex, Location location)
-            : base(container, underlyingField, tupleElementIndex, location)
+        public TupleVirtualElementFieldSymbol(TupleTypeSymbol container, FieldSymbol underlyingField, string name, int tupleElementIndex, Location location, bool isImplicitlyDeclared)
+            : base(container, underlyingField, tupleElementIndex, location, isImplicitlyDeclared)
         {
             Debug.Assert(name != null);
             Debug.Assert(name != underlyingField.Name || !container.UnderlyingNamedType.Equals(underlyingField.ContainingType, TypeCompareKind.IgnoreDynamicAndTupleNames),

src/Compilers/CSharp/Portable/Symbols/Tuples/TupleTypeSymbol.cs

@@ -820,7 +820,9 @@ private ImmutableArray<Symbol> CreateMembers()
                                 var providedName = _elementNames.IsDefault ? null : _elementNames[tupleFieldIndex];
                                 var location = _elementLocations.IsDefault ? null : _elementLocations[tupleFieldIndex];
                                 var defaultName = TupleMemberName(tupleFieldIndex + 1);
-                                var providedIsNotDefault = providedName != defaultName;
+                                // if provided name does not match the default one, 
+                                // then default element as declared implicitly
+                                var defaultImplicitlyDeclared = providedName != defaultName;
 
                                 var fieldSymbol = field.AsMember(currentUnderlying);
 
@@ -831,29 +833,29 @@ private ImmutableArray<Symbol> CreateMembers()
                                     // Add a field with default name. It should be present regardless.
                                     // Make it virtual since we are not at the top level
                                     // tupleFieldIndex << 1 because this is a default element
-                                    members.Add(new TupleVirtualElementFieldSymbol(this, fieldSymbol, defaultName, tupleFieldIndex << 1, location));
+                                    members.Add(new TupleVirtualElementFieldSymbol(this, fieldSymbol, defaultName, tupleFieldIndex << 1, location, defaultImplicitlyDeclared));
 
-                                    if (providedIsNotDefault && providedName != null)
+                                    if (defaultImplicitlyDeclared && providedName != null)
                                     {
                                         // The name given doesn't match default name Item8, etc.
                                         // Add a field with the given name
                                         // tupleFieldIndex << 1 + 1, because this is not a default element
-                                        members.Add(new TupleVirtualElementFieldSymbol(this, fieldSymbol, providedName, (tupleFieldIndex << 1) + 1, location));
+                                        members.Add(new TupleVirtualElementFieldSymbol(this, fieldSymbol, providedName, (tupleFieldIndex << 1) + 1, location, isImplicitlyDeclared: false));
                                     }
                                 }
-                                else if (providedIsNotDefault)
+                                else if (defaultImplicitlyDeclared)
                                 {
                                     Debug.Assert(fieldSymbol.Name == defaultName, "top level underlying field must match default name");
 
                                     // Add the underlying field as an element. It should have the default name.
                                     // tupleFieldIndex << 1 because this is a default element
-                                    members.Add(new TupleElementFieldSymbol(this, fieldSymbol, tupleFieldIndex << 1, location));
+                                    members.Add(new TupleElementFieldSymbol(this, fieldSymbol, tupleFieldIndex << 1, location, defaultImplicitlyDeclared));
 
                                     if (providedName != null)
                                     {
                                         // Add a field with the given name
                                         // tupleFieldIndex << 1 + 1, because this is not a default element
-                                        members.Add(new TupleVirtualElementFieldSymbol(this, fieldSymbol, providedName, (tupleFieldIndex << 1) + 1, location));
+                                        members.Add(new TupleVirtualElementFieldSymbol(this, fieldSymbol, providedName, (tupleFieldIndex << 1) + 1, location, isImplicitlyDeclared: false));
                                     }
                                 }
                                 else
@@ -861,7 +863,7 @@ private ImmutableArray<Symbol> CreateMembers()
                                     Debug.Assert(fieldSymbol.Name == defaultName, "top level underlying field must match default name");
 
                                     // tupleFieldIndex << 1 because this is a default element
-                                    members.Add(new TupleElementFieldSymbol(this, fieldSymbol, tupleFieldIndex << 1, location));
+                                    members.Add(new TupleElementFieldSymbol(this, fieldSymbol, tupleFieldIndex << 1, location, isImplicitlyDeclared: false));
                                 }
 
                                 elementsMatchedByFields[tupleFieldIndex] = true; // mark as handled
@@ -944,18 +946,20 @@ private ImmutableArray<Symbol> CreateMembers()
                     var providedName = _elementNames.IsDefault ? null : _elementNames[i];
                     var location = _elementLocations.IsDefault ? null : _elementLocations[i];
                     var defaultName = TupleMemberName(i + 1);
-                    var providedIsNotDefault = providedName != defaultName;
+                    // if provided name does not match the default one, 
+                    // then default element as declared implicitly
+                    var defaultImplicitlyDeclared = providedName != defaultName;
 
                     // Add default element field. 
                     // i << 1 because this is a default element
-                    members.Add(new TupleErrorFieldSymbol(this, defaultName, i << 1, providedIsNotDefault ? null: location, _elementTypes[i], diagnosticInfo));
+                    members.Add(new TupleErrorFieldSymbol(this, defaultName, i << 1, defaultImplicitlyDeclared ? null: location, _elementTypes[i], diagnosticInfo, defaultImplicitlyDeclared));
 
 
-                    if (providedIsNotDefault && providedName != null)
+                    if (defaultImplicitlyDeclared && providedName != null)
                     {
                         // Add frieldly named element field. 
                         // (i << 1) + 1, because this is not a default element
-                        members.Add(new TupleErrorFieldSymbol(this, providedName, (i << 1) + 1, location, _elementTypes[i], diagnosticInfo));
+                        members.Add(new TupleErrorFieldSymbol(this, providedName, (i << 1) + 1, location, _elementTypes[i], diagnosticInfo, isImplicitlyDeclared: false));
                     }
                 }
             }

src/Compilers/CSharp/Test/Emit/CodeGen/CodeGenTupleTest.cs

@@ -3292,7 +3292,7 @@ static void Main()
             Assert.True(mItem1.GetAttributes().IsEmpty);
             Assert.Null(mItem1.GetUseSiteDiagnostic());
             Assert.True(mItem1.Locations.IsEmpty);
-            Assert.False(mItem1.IsImplicitlyDeclared);
+            Assert.True(mItem1.IsImplicitlyDeclared);
             Assert.Null(mItem1.TypeLayoutOffset);
         }
 
@@ -3967,8 +3967,8 @@ public ValueTuple(T1 item1, T2 item2)
             Assert.Equal("error CS8128: Member 'Item1' was not found on type 'ValueTuple<T1, T2>' from assembly 'comp, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null'.",
                          mItem1.GetUseSiteDiagnostic().ToString());
             Assert.True(mItem1.Locations.IsDefaultOrEmpty);
-            Assert.Equal("string", mItem1.DeclaringSyntaxReferences.Single().GetSyntax().ToString());
-            Assert.False(mItem1.IsImplicitlyDeclared);
+            Assert.True(mItem1.DeclaringSyntaxReferences.IsDefaultOrEmpty);
+            Assert.True(mItem1.IsImplicitlyDeclared);
             Assert.Null(mItem1.TypeLayoutOffset);
 
             AssertTestDisplayString(mTuple.GetMembers(),
@@ -8658,9 +8658,9 @@ static void Main()
             Assert.True(m1Item1.GetAttributes().IsEmpty);
             Assert.Null(m1Item1.GetUseSiteDiagnostic());
             Assert.False(m1Item1.Locations.IsDefaultOrEmpty);
-            Assert.Equal("int", m1Item1.DeclaringSyntaxReferences.Single().GetSyntax().ToString());
+            Assert.True(m1Item1.DeclaringSyntaxReferences.IsDefaultOrEmpty);
             Assert.Equal("Item1", m1Item1.TupleUnderlyingField.Name);
-            Assert.False(m1Item1.IsImplicitlyDeclared);
+            Assert.True(m1Item1.IsImplicitlyDeclared);
             Assert.Null(m1Item1.TypeLayoutOffset);
 
             Assert.True(m2Item1.IsTupleField);
@@ -8676,8 +8676,10 @@ static void Main()
             Assert.False(m2Item1.Locations.IsDefaultOrEmpty);
             Assert.Equal("Item1", m2Item1.Name);
             Assert.Equal("Item1", m2Item1.TupleUnderlyingField.Name);
-            Assert.Equal(m2Item1.Locations.Single(), m2Item1.TupleUnderlyingField.Locations.Single());
-            Assert.False(m2Item1.IsImplicitlyDeclared);
+            Assert.NotEqual(m2Item1.Locations.Single(), m2Item1.TupleUnderlyingField.Locations.Single());
+            Assert.Equal("MetadataFile(System.ValueTuple.dll)", m2Item1.TupleUnderlyingField.Locations.Single().ToString());
+            Assert.Equal("SourceFile([826..828))", m2Item1.Locations.Single().ToString());
+            Assert.True(m2Item1.IsImplicitlyDeclared);
             Assert.Null(m2Item1.TypeLayoutOffset);
 
             Assert.True(m2a2.IsTupleField);
@@ -8905,9 +8907,9 @@ static void Main()
             Assert.True(m3Item8.GetAttributes().IsEmpty);
             Assert.Null(m3Item8.GetUseSiteDiagnostic());
             Assert.False(m3Item8.Locations.IsDefaultOrEmpty);
-            Assert.Equal("int", m3Item8.DeclaringSyntaxReferences.Single().GetSyntax().ToString());
+            Assert.True(m3Item8.DeclaringSyntaxReferences.IsDefaultOrEmpty);
             Assert.Equal("Item1", m3Item8.TupleUnderlyingField.Name);
-            Assert.False(m3Item8.IsImplicitlyDeclared);
+            Assert.True(m3Item8.IsImplicitlyDeclared);
             Assert.Null(m3Item8.TypeLayoutOffset);
 
             var m3TupleRestTuple = (NamedTypeSymbol)((FieldSymbol)m3Tuple.GetMembers("Rest").Single()).Type;
@@ -9100,7 +9102,7 @@ static void Main()
             Assert.Null(m4Item8.GetUseSiteDiagnostic());
             Assert.False(m4Item8.Locations.IsDefaultOrEmpty);
             Assert.Equal("Item1", m4Item8.TupleUnderlyingField.Name);
-            Assert.False(m4Item8.IsImplicitlyDeclared);
+            Assert.True(m4Item8.IsImplicitlyDeclared);
             Assert.Null(m4Item8.TypeLayoutOffset);
 
             var m4h4 = (FieldSymbol)m4Tuple.GetMembers("h4").Single();
@@ -9719,7 +9721,7 @@ static void Main()
             Assert.Null(m8Item8.GetUseSiteDiagnostic());
             Assert.False(m8Item8.Locations.IsDefaultOrEmpty);
             Assert.Equal("Item1", m8Item8.TupleUnderlyingField.Name);
-            Assert.False(m8Item8.IsImplicitlyDeclared);
+            Assert.True(m8Item8.IsImplicitlyDeclared);
             Assert.Null(m8Item8.TypeLayoutOffset);
 
             var m8Item1 = (FieldSymbol)m8Tuple.GetMembers("Item1").Last();
@@ -9918,9 +9920,9 @@ static void Main()
             Assert.True(m1Item1.GetAttributes().IsEmpty);
             Assert.Null(m1Item1.GetUseSiteDiagnostic());
             Assert.False(m1Item1.Locations.IsDefaultOrEmpty);
-            Assert.Equal("1", m1Item1.DeclaringSyntaxReferences.Single().GetSyntax().ToString());
+            Assert.True(m1Item1.DeclaringSyntaxReferences.IsDefaultOrEmpty);
             Assert.Equal("Item1", m1Item1.TupleUnderlyingField.DeclaringSyntaxReferences.Single().GetSyntax().ToString());
-            Assert.False(m1Item1.IsImplicitlyDeclared);
+            Assert.True(m1Item1.IsImplicitlyDeclared);
             Assert.Null(m1Item1.TypeLayoutOffset);
 
             Assert.True(m2Item1.IsTupleField);
@@ -9934,10 +9936,12 @@ static void Main()
             Assert.True(m2Item1.GetAttributes().IsEmpty);
             Assert.Null(m2Item1.GetUseSiteDiagnostic());
             Assert.False(m2Item1.Locations.IsDefaultOrEmpty);
-            Assert.Equal("a2", m2Item1.DeclaringSyntaxReferences.Single().GetSyntax().ToString());
+            Assert.True(m2Item1.DeclaringSyntaxReferences.IsDefaultOrEmpty);
             Assert.Equal("Item1", m2Item1.TupleUnderlyingField.DeclaringSyntaxReferences.Single().GetSyntax().ToString());
-            Assert.Equal(m2Item1.Locations.Single(), m2Item1.TupleUnderlyingField.Locations.Single());
-            Assert.False(m2Item1.IsImplicitlyDeclared);
+            Assert.NotEqual(m2Item1.Locations.Single(), m2Item1.TupleUnderlyingField.Locations.Single());
+            Assert.Equal("SourceFile([891..896))", m2Item1.TupleUnderlyingField.Locations.Single().ToString());
+            Assert.Equal("SourceFile([196..198))", m2Item1.Locations.Single().ToString());
+            Assert.True(m2Item1.IsImplicitlyDeclared);
             Assert.Null(m2Item1.TypeLayoutOffset);
 
             Assert.True(m2a2.IsTupleField);

src/EditorFeatures/Core/Implementation/RenameTracking/RenameTrackingTaggerProvider.TrackingSession.cs

@@ -208,7 +208,7 @@ private async Task<TriggerIdentifierKind> DetermineIfRenamableSymbolAsync(ISymbo
                 // Get the source symbol if possible
                 var sourceSymbol = await SymbolFinder.FindSourceDefinitionAsync(symbol, document.Project.Solution, _cancellationToken).ConfigureAwait(false) ?? symbol;
 
-                if (!sourceSymbol.Locations.All(loc => loc.IsInSource))
+                if (sourceSymbol.IsImplicitlyDeclared || !sourceSymbol.Locations.All(loc => loc.IsInSource))
                 {
                     return TriggerIdentifierKind.NotRenamable;
                 }

src/EditorFeatures/Test/RenameTracking/RenameTrackingTaggerProviderTests.cs

@@ -1194,5 +1194,121 @@ void M()
                 Assert.NotEmpty(await state.GetDocumentDiagnosticsAsync());
             }
         }
+
+        [WpfFact]
+        [Trait(Traits.Feature, Traits.Features.RenameTracking)]
+        public async Task RenameImplicitTupleField()
+        {
+            var code = @"
+class C
+{
+    void M()
+    {
+        (int, int) x = (1, 2);
+        var y = x.Item1$$;
+    }
+}";
+            using (var state = await RenameTrackingTestState.CreateAsync(code, LanguageNames.CSharp))
+            {
+                state.EditorOperations.Backspace();
+                state.EditorOperations.Backspace();
+                await state.AssertNoTag();
+                Assert.Empty(await state.GetDocumentDiagnosticsAsync());
+            }
+        }
+
+        [WpfFact]
+        [Trait(Traits.Feature, Traits.Features.RenameTracking)]
+        public async Task RenameImplicitTupleFieldExtended()
+        {
+            var code = @"
+class C
+{
+    void M()
+    {
+        (int, int, int, int, int, int, int, int, int, int) x = (1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+        var y = x.Item9$$;
+    }
+}
+";
+            using (var state = await RenameTrackingTestState.CreateAsync(code, LanguageNames.CSharp))
+            {
+                state.EditorOperations.Backspace();
+                state.EditorOperations.Backspace();
+                await state.AssertNoTag();
+                Assert.Empty(await state.GetDocumentDiagnosticsAsync());
+            }
+        }
+
+
+        [WpfFact]
+        [Trait(Traits.Feature, Traits.Features.RenameTracking)]
+        public async Task RenameExplicitTupleField()
+        {
+            var code = @"
+class C
+{
+    void M()
+    {
+        (int Item1, int) x = (1, 2);
+        var y = x.Item1$$;
+    }
+}";
+            using (var state = await RenameTrackingTestState.CreateAsync(code, LanguageNames.CSharp))
+            {
+                state.EditorOperations.Backspace();
+                state.EditorOperations.Backspace();
+
+                await state.AssertTag("Item1", "Ite", invokeAction: true);
+
+                // Make sure the rename completed            
+                var expectedCode = @"
+class C
+{
+    void M()
+    {
+        (int Ite, int) x = (1, 2);
+        var y = x.Ite;
+    }
+}";
+                Assert.Equal(expectedCode, state.HostDocument.TextBuffer.CurrentSnapshot.GetText());
+                await state.AssertNoTag();
+            }
+        }
+
+        [WpfFact]
+        [Trait(Traits.Feature, Traits.Features.RenameTracking)]
+        public async Task RenameExplicitTupleFieldExtended()
+        {
+            var code = @"
+class C
+{
+    void M()
+    {
+        (int, int, int, int, int, int, int, int, int Item9, int) x = (1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+        var y = x.Item9$$;
+    }
+}";
+            using (var state = await RenameTrackingTestState.CreateAsync(code, LanguageNames.CSharp))
+            {
+                state.EditorOperations.Backspace();
+                state.EditorOperations.Backspace();
+
+                await state.AssertTag("Item9", "Ite", invokeAction: true);
+
+                // Make sure the rename completed            
+                var expectedCode = @"
+class C
+{
+    void M()
+    {
+        (int, int, int, int, int, int, int, int, int Ite, int) x = (1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+        var y = x.Ite;
+    }
+}";
+                Assert.Equal(expectedCode, state.HostDocument.TextBuffer.CurrentSnapshot.GetText());
+                await state.AssertNoTag();
+            }
+        }
     }
 }