Responding to PR Feedback

Responding to peer review feedback. Updated to never consider user
defined narrowing conversions unnecessary.

src/EditorFeatures/Test/Workspaces/TestWorkspaceFactory.cs

@@ -50,7 +50,6 @@ public partial class TestWorkspaceFactory
         private const string AnalyzerDisplayAttributeName = "Name";
         private const string AnalyzerFullPathAttributeName = "FullPath";
         private const string AliasAttributeName = "Alias";
-        private const string DiagnosticOptionElementName = "DiagnosticOption";
 
         /// <summary>
         /// Creates a single buffer in a workspace.

src/EditorFeatures/Test/Workspaces/TestWorkspaceFactory_XmlConsumption.cs

@@ -398,7 +398,6 @@ private static CompilationOptions CreateCompilationOptions(TestWorkspace workspa
             var rootNamespace = new VisualBasicCompilationOptions(OutputKind.ConsoleApplication).RootNamespace;
             var globalImports = new List<GlobalImport>();
             var reportDiagnostic = ReportDiagnostic.Default;
-            var specificDiagnostics = ImmutableDictionary.Create<string, ReportDiagnostic>();
 
             if (compilationOptionsElement != null)
             {
@@ -430,10 +429,6 @@ private static CompilationOptions CreateCompilationOptions(TestWorkspace workspa
                        : new VisualBasicCompilationOptions(OutputKind.WindowsRuntimeMetadata).WithGlobalImports(globalImports)
                                                                          .WithRootNamespace(rootNamespace);
                 }
-
-                specificDiagnostics = compilationOptionsElement.Elements(DiagnosticOptionElementName)
-                    .Select(x => KeyValuePair.Create(x.Value, (ReportDiagnostic)Enum.Parse(typeof(ReportDiagnostic), x.Attribute(ReportDiagnosticAttributeName).Value)))
-                    .ToImmutableDictionary();
             }
             else
             {
@@ -451,8 +446,7 @@ private static CompilationOptions CreateCompilationOptions(TestWorkspace workspa
                                                    .WithSourceReferenceResolver(SourceFileResolver.Default)
                                                    .WithXmlReferenceResolver(XmlFileResolver.Default)
                                                    .WithMetadataReferenceResolver(new AssemblyReferenceResolver(MetadataFileReferenceResolver.Default, MetadataFileReferenceProvider.Default))
-                                                   .WithAssemblyIdentityComparer(DesktopAssemblyIdentityComparer.Default)
-                                                   .WithSpecificDiagnosticOptions(specificDiagnostics);
+                                                   .WithAssemblyIdentityComparer(DesktopAssemblyIdentityComparer.Default);
 
             if (language == LanguageNames.VisualBasic)
             {

src/EditorFeatures/Test/Workspaces/TestWorkspaceFactory_XmlCreation.cs

@@ -75,18 +75,6 @@ private static XElement CreateCompilationOptionsElement(CompilationOptions optio
                     element.SetAttributeValue(RootNamespaceAttributeName, vbOptions.RootNamespace);
                 }
 
-                if (vbOptions.SpecificDiagnosticOptions?.Any() == true)
-                {
-                    element.Add(
-                    vbOptions.SpecificDiagnosticOptions.AsEnumerable().Select(
-                        i =>
-                        {
-                            var x = new XElement(DiagnosticOptionElementName, i.Key);
-                            x.SetAttributeValue(ReportDiagnosticAttributeName, System.Enum.GetName(typeof(ReportDiagnostic), i.Value));
-                            return x;
-                        }));
-                }
-
                 return element;
             }
 

src/EditorFeatures/VisualBasicTest/Diagnostics/AbstractVisualBasicDiagnosticProviderBasedUserDiagnosticTest.vb

@@ -32,15 +32,11 @@ Namespace Microsoft.CodeAnalysis.Editor.VisualBasic.UnitTests.Diagnostics
             Return input.Replace("\n", vbCrLf)
         End Function
 
-        Protected Overloads Sub Test(initialMarkup As XElement, expected As XElement, Optional index As Integer = 0, Optional compareTokens As Boolean = True, Optional compilationOptions As VisualBasicCompilationOptions = Nothing)
+        Protected Overloads Sub Test(initialMarkup As XElement, expected As XElement, Optional index As Integer = 0, Optional compareTokens As Boolean = True)
             Dim initialMarkupStr = initialMarkup.ConvertTestSourceTag()
             Dim expectedStr = expected.ConvertTestSourceTag()
 
-            If compilationOptions Is Nothing Then
-                compilationOptions = CType(_compilationOptions, VisualBasicCompilationOptions)
-            End If
-
-            MyBase.Test(initialMarkupStr, expectedStr, parseOptions:=Nothing, compilationOptions:=compilationOptions, index:=index, compareTokens:=compareTokens)
+            MyBase.Test(initialMarkupStr, expectedStr, parseOptions:=Nothing, compilationOptions:=_compilationOptions, index:=index, compareTokens:=compareTokens)
         End Sub
 
         Protected Overloads Sub TestMissingWithWorkspaceXml(initialMarkup As XElement)

src/EditorFeatures/VisualBasicTest/Diagnostics/RemoveUnnecessaryCast/RemoveUnnecessaryCastTests.vb

@@ -2697,7 +2697,7 @@ End Class
 
         <WorkItem(3163, "https://github.com/dotnet/roslyn/issues/3163")>
         <Fact, Trait(Traits.Feature, Traits.Features.CodeActionsRemoveUnnecessaryCast)>
-        Public Sub DoNotRemoveCastInNarrowingConverionWihtOptionStrictOn()
+        Public Sub DoNotRemoveCastInUserDefinedNarrowingConverionStrictOn()
             Dim markup =
 <File>
 Option Strict On
@@ -2736,7 +2736,7 @@ End Structure
 
         <WorkItem(3163, "https://github.com/dotnet/roslyn/issues/3163")>
         <Fact, Trait(Traits.Feature, Traits.Features.CodeActionsRemoveUnnecessaryCast)>
-        Public Sub DoNotRemoveCastInNarrowingConverionWihtOptionStrictOffBC42016AsWarning()
+        Public Sub DoNotRemoveCastInUserDefinedNarrowingConverionStrictOff()
             Dim markup =
 <File>
 Option Strict Off
@@ -2772,79 +2772,5 @@ End Structure
 </File>
             TestMissing(markup)
         End Sub
-
-        <WorkItem(3163, "https://github.com/dotnet/roslyn/issues/3163")>
-        <Fact, Trait(Traits.Feature, Traits.Features.CodeActionsRemoveUnnecessaryCast)>
-        Public Sub RemoveCastInNarrowingConverionWihtOptionStrictOffBC42016Suppressed()
-            Dim markup =
-<File>
-Option Strict Off
-
-Module Module1
-
-    Sub Main()
-        Dim red = ColorF.FromArgb(255, 255, 0, 0)
-        Dim c As Color = [|CType(red, Color)|]
-    End Sub
-
-End Module
-
-Public Structure ColorF
-    Public A, R, G, B As Single
-    Public Shared Function FromArgb(a As Double, r As Double, g As Double, b As Double) As ColorF
-        Return New ColorF With {.A = CSng(a), .R = CSng(r), .G = CSng(g), .B = CSng(b)}
-    End Function
-    Public Shared Widening Operator CType(x As Color) As ColorF
-        Return ColorF.FromArgb(x.A / 255, x.R / 255, x.G / 255, x.B / 255)
-    End Operator
-    Public Shared Narrowing Operator CType(x As ColorF) As Color
-        Return Color.FromArgb(CByte(x.A * 255), CByte(x.R * 255), CByte(x.G * 255), CByte(x.B * 255))
-    End Operator
-End Structure
-
-Public Structure Color
-    Public A, R, G, B As Byte
-    Public Shared Function FromArgb(a As Byte, r As Byte, g As Byte, b As Byte) As Color
-        Return New Color With {.A = a, .R = r, .G = g, .B = b}
-    End Function
-End Structure
-</File>
-            Dim expected =
-<File>
-Option Strict Off
-
-Module Module1
-
-    Sub Main()
-        Dim red = ColorF.FromArgb(255, 255, 0, 0)
-        Dim c As Color = red
-    End Sub
-
-End Module
-
-Public Structure ColorF
-    Public A, R, G, B As Single
-    Public Shared Function FromArgb(a As Double, r As Double, g As Double, b As Double) As ColorF
-        Return New ColorF With {.A = CSng(a), .R = CSng(r), .G = CSng(g), .B = CSng(b)}
-    End Function
-    Public Shared Widening Operator CType(x As Color) As ColorF
-        Return ColorF.FromArgb(x.A / 255, x.R / 255, x.G / 255, x.B / 255)
-    End Operator
-    Public Shared Narrowing Operator CType(x As ColorF) As Color
-        Return Color.FromArgb(CByte(x.A * 255), CByte(x.R * 255), CByte(x.G * 255), CByte(x.B * 255))
-    End Operator
-End Structure
-
-Public Structure Color
-    Public A, R, G, B As Byte
-    Public Shared Function FromArgb(a As Byte, r As Byte, g As Byte, b As Byte) As Color
-        Return New Color With {.A = a, .R = r, .G = g, .B = b}
-    End Function
-End Structure
-</File>
-            Dim compilationOptions = New VisualBasicCompilationOptions(OutputKind.ConsoleApplication).WithOptionInfer(True)
-            compilationOptions = compilationOptions.WithSpecificDiagnosticOptions(compilationOptions.SpecificDiagnosticOptions.Add("BC42016", ReportDiagnostic.Suppress))
-            Test(markup, expected, compareTokens:=False, compilationOptions:=compilationOptions)
-        End Sub
     End Class
 End Namespace

src/Workspaces/VisualBasic/Portable/Extensions/CastAnalyzer.vb

@@ -254,7 +254,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Extensions
                     Return (HaveSameUserDefinedConversion(expressionToCastType, expressionToOuterType) OrElse
                             HaveSameUserDefinedConversion(castToOuterType, expressionToOuterType)) AndAlso
                            (UserDefinedConversionIsAllowed(_castNode, _semanticModel) AndAlso
-                            NarrowingConversionIsAllowed(expressionToCastType, _semanticModel))
+                            Not expressionToCastType.IsNarrowing)
                 ElseIf expressionToOuterType.IsUserDefined Then
                     Return False
                 End If
@@ -343,28 +343,6 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Extensions
             Return True
         End Function
 
-        Private Shared Function NarrowingConversionIsAllowed(conversion As Conversion, semanticModel As SemanticModel) As Boolean
-            ' If this is not a narrowing conversion then no VB compiler options will disallow it
-            If conversion.IsNarrowing Then
-                ' If Option Strict is On then all narrowing conversions are illegal
-                If semanticModel.OptionStrict = OptionStrict.On Then
-                    Return False
-                Else
-                    ' For all other cases we only want to label a cast as unnecessary if BC42016 is suppressed, 
-                    ' otherwise removing the cast will cause a warning or error to be shown to the user.
-                    Dim reportDiagnostic As ReportDiagnostic
-                    If semanticModel.Compilation.Options.SpecificDiagnosticOptions.TryGetValue("BC42016", reportDiagnostic) AndAlso
-                       reportDiagnostic = ReportDiagnostic.Suppress Then
-                        Return True
-                    Else
-                        Return False
-                    End If
-                End If
-            End If
-
-            Return True
-        End Function
-
         Private Shared Function IsRequiredWideningNumericConversion(sourceType As ITypeSymbol, destinationType As ITypeSymbol) As Boolean
             ' VB Language Specification: Section 8.3 Numeric Conversions