Fix Tuple Crefs causing null exception (dotnet#29513)

Fix Tuple Crefs causing null exception: - fix the Cref binder so that we un-wrap any TupleTypeSymbols that get wrapped inside BindNamespaceOrTypeSymbol as crefs don't consider the higher order form tuples at all. - Add tests
alatas · Sep 11, 2018 · e82d1ad · e82d1ad
1 parent 8474ba4
commit e82d1ad
Show file tree

Hide file tree

Showing 3 changed files with 114 additions and 0 deletions.
diff --git a/src/Compilers/CSharp/Portable/Binder/Binder_Crefs.cs b/src/Compilers/CSharp/Portable/Binder/Binder_Crefs.cs
@@ -92,6 +92,12 @@ private NamespaceOrTypeSymbol BindNamespaceOrTypeSymbolInCref(TypeSyntax syntax)
             NamespaceOrTypeSymbol namespaceOrTypeSymbol = BindNamespaceOrTypeSymbol(syntax, unusedDiagnostics);
             unusedDiagnostics.Free();
 
+            // BindNamespaceOrTypeSymbol will wrap any tuple types in a TupleTypeSymbol. We unwrap it here, as doc comments don't consider the (T,T) form of tuples
+            if(namespaceOrTypeSymbol is TupleTypeSymbol t)
+            {
+                namespaceOrTypeSymbol = t.UnderlyingNamedType;
+            }
+
             Debug.Assert((object)namespaceOrTypeSymbol != null);
             return namespaceOrTypeSymbol;
         }

diff --git a/src/Compilers/CSharp/Test/Symbol/DocumentationComments/CrefTests.cs b/src/Compilers/CSharp/Test/Symbol/DocumentationComments/CrefTests.cs
@@ -6660,5 +6660,53 @@ void S()
             var parameterSymbol = ((MethodSymbol)model.GetSymbolInfo(cref).Symbol).Parameters.Single();
             Assert.Equal(RefKind.In, parameterSymbol.RefKind);
         }
+
+        [Fact]
+        public void Cref_TupleType()
+        {
+            var source = @"
+using System;
+/// <summary>
+/// See <see cref=""ValueTuple{T,T}""/>.
+/// </summary>
+class C
+{
+}
+";
+            var parseOptions = TestOptions.RegularWithDocumentationComments;
+            var options = TestOptions.ReleaseDll.WithXmlReferenceResolver(XmlFileResolver.Default);
+            var compilation = CreateCompilation(source, parseOptions: parseOptions, options: options, targetFramework: TargetFramework.StandardAndCSharp);
+            var cMember = compilation.GetMember<NamedTypeSymbol>("C");
+            var xmlDocumentationString = cMember.GetDocumentationCommentXml();
+
+            var xml = System.Xml.Linq.XDocument.Parse(xmlDocumentationString);
+            var cref = xml.Descendants("see").Single().Attribute("cref").Value;
+
+            Assert.Equal("T:System.ValueTuple`2", cref);
+        }
+
+        [Fact]
+        public void Cref_TupleTypeField()
+        {
+            var source = @"
+using System;
+/// <summary>
+/// See <see cref=""ValueTuple{Int32,Int32}.Item1""/>.
+/// </summary>
+class C
+{
+}
+";
+            var parseOptions = TestOptions.RegularWithDocumentationComments;
+            var options = TestOptions.ReleaseDll.WithXmlReferenceResolver(XmlFileResolver.Default);
+            var compilation = CreateCompilation(source, parseOptions: parseOptions, options: options, targetFramework: TargetFramework.StandardAndCSharp);
+            var cMember = compilation.GetMember<NamedTypeSymbol>("C");
+            var xmlDocumentationString = cMember.GetDocumentationCommentXml();
+
+            var xml = System.Xml.Linq.XDocument.Parse(xmlDocumentationString);
+            var cref = xml.Descendants("see").Single().Attribute("cref").Value;
+
+            Assert.Equal("F:System.ValueTuple`2.Item1", cref);
+        }
     }
 }
diff --git a/src/Compilers/VisualBasic/Test/Symbol/DocumentationComments/DocCommentTests.vb b/src/Compilers/VisualBasic/Test/Symbol/DocumentationComments/DocCommentTests.vb
@@ -12447,5 +12447,65 @@ End Class
             Assert.Empty(model.LookupSymbols(name.SpanStart, typeParameter, "GetAwaiter"))
         End Sub
 
+        <Fact>
+        Public Sub LookupOnCrefOfTupleType()
+
+            Dim sources =
+<compilation>
+    <file name="a.vb">
+        <![CDATA[
+Imports System
+''' <summary>
+''' <see cref="ValueTuple(Of U,U)"/>
+''' </summary>
+Public Class Test
+End Class
+]]>
+    </file>
+</compilation>
+
+            Dim references = TargetFrameworkUtil.GetReferences(TargetFramework.StandardAndVBRuntime)
+            Dim compilation = CreateEmptyCompilationWithReferences(
+                sources,
+                references)
+
+            Dim cMember = compilation.GetMember(Of NamedTypeSymbol)("Test")
+            Dim xmlDocumentationString = cMember.GetDocumentationCommentXml()
+            Dim xml = System.Xml.Linq.XDocument.Parse(xmlDocumentationString)
+            Dim cref = xml.Descendants("see").Single().Attribute("cref").Value
+
+            Assert.Equal("T:System.ValueTuple`2", cref)
+        End Sub
+
+        <Fact>
+        Public Sub LookupOnCrefOfTupleTypeField()
+
+            Dim sources =
+<compilation>
+    <file name="a.vb">
+        <![CDATA[
+Imports System
+''' <summary>
+''' <see cref="ValueTuple(Of U,U).Item1"/>
+''' </summary>
+Public Class Test
+End Class
+]]>
+    </file>
+</compilation>
+
+            Dim references = TargetFrameworkUtil.GetReferences(TargetFramework.StandardAndVBRuntime)
+            Dim compilation = CreateEmptyCompilationWithReferences(
+                sources,
+                references)
+
+            Dim cMember = compilation.GetMember(Of NamedTypeSymbol)("Test")
+            Dim xmlDocumentationString = cMember.GetDocumentationCommentXml()
+            Dim xml = System.Xml.Linq.XDocument.Parse(xmlDocumentationString)
+            Dim cref = xml.Descendants("see").Single().Attribute("cref").Value
+
+            Assert.Equal("F:System.ValueTuple`2.Item1", cref)
+        End Sub
+
     End Class
 End Namespace