Merge pull request #45102 from paul1956/fixCastAnalyzerIsUnnecessary

FIx Redundant Cast incorrect for SimpleArguments #44516

src/Analyzers/VisualBasic/Tests/RemoveUnnecessaryCast/RemoveUnnecessaryCastTests.vb

@@ -31,6 +31,40 @@ End Module
             Await TestMissingAsync(markup)
         End Function
 
+        <Fact, Trait(Traits.Feature, Traits.Features.CodeActionsRemoveUnnecessaryCast)>
+        Public Async Function TestDontRemoveCastSimpleArgument1() As Task
+            Dim markup =
+<File>
+Option Strict On
+Imports System.Drawing
+Module M
+    Sub Main()
+       ' test PredefinedCastExpressionSyntax and WalkDownParentheses
+        Dim x As New Point([|CInt((System.Math.Floor(1.1)))|], 1)
+    End Sub
+End Module
+</File>
+
+            Await TestMissingAsync(markup)
+        End Function
+
+        <Fact, Trait(Traits.Feature, Traits.Features.CodeActionsRemoveUnnecessaryCast)>
+        Public Async Function TestDontRemoveCastSimpleArgument2() As Task
+            Dim markup =
+<File>
+Option Strict On    
+Imports System.Drawing
+Module M
+    Sub Main()
+      ' test CastExpressionSyntax
+       Dim y As New Point([|CType(1.1, Integer)|], 1)
+    End Sub
+End Module
+</File>
+
+            Await TestMissingAsync(markup)
+        End Function
+
         <WorkItem(545148, "http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/545148")>
         <Fact, Trait(Traits.Feature, Traits.Features.CodeActionsRemoveUnnecessaryCast)>
         Public Async Function TestParenthesizeToKeepParseTheSame1() As Task
@@ -38,7 +72,7 @@ End Module
 <File>
 Imports System.Collections
 Imports System.Linq
- 
+
 Module Program
     Sub Main
         Dim a = CType([|CObj(From x In "" Select x)|], IEnumerable)
@@ -50,7 +84,7 @@ End Module
 <File>
 Imports System.Collections
 Imports System.Linq
- 
+
 Module Program
     Sub Main
         Dim a = CType((From x In "" Select x), IEnumerable)
@@ -1121,7 +1155,7 @@ Module Program
         Dim a = {[|CLng(Nothing)|]}
         Goo(a)
     End Sub
- 
+
     Sub Goo(a() As Long)
     End Sub
 End Module
@@ -1899,7 +1933,7 @@ Imports System
 Interface I
     Property A As Action
 End Interface
- 
+
 Class C
     Implements I
     Property A As Action = [|CType(Sub() If True Then, Action)|] Implements I.A
@@ -1912,7 +1946,7 @@ Imports System
 Interface I
     Property A As Action
 End Interface
- 
+
 Class C
     Implements I
     Property A As Action = (Sub() If True Then) Implements I.A
@@ -1991,7 +2025,7 @@ Imports System
 Module Program
     Sub Main()
         Dim x As Action = Sub() Console.WriteLine("Hello")
-        [|CType(x, Action)|] : Console.WriteLine() 
+        [|CType(x, Action)|] : Console.WriteLine()
     End Sub
 End Module
 
@@ -2003,7 +2037,7 @@ Imports System
 Module Program
     Sub Main()
         Dim x As Action = Sub() Console.WriteLine("Hello")
-        x() : Console.WriteLine() 
+        x() : Console.WriteLine()
     End Sub
 End Module
 
@@ -2167,7 +2201,7 @@ Class M
     Shared Sub Main()
         [|CType(New M(), I1).Goo()|]
     End Sub
- 
+
     Public Sub Goo() Implements I1.Goo
     End Sub
 End Class
@@ -2356,11 +2390,11 @@ Class X
 End Class
 
 Class Y
-	Inherits X
-	Implements IDisposable
-	Private Sub IDisposable_Dispose() Implements IDisposable.Dispose
-		Console.WriteLine("Y.Dispose")
-	End Sub
+    Inherits X
+    Implements IDisposable
+    Private Sub IDisposable_Dispose() Implements IDisposable.Dispose
+        Console.WriteLine("Y.Dispose")
+    End Sub
 End Class
 </File>
 
@@ -2486,7 +2520,7 @@ End Class
         Public Async Function TestDontRemoveCastToInterfaceForSealedType5() As Task
             ' Note: The cast below cannot be removed (even though C is sealed)
             ' because default values differ for optional parameters and
-            ' hence the method is not considered an implementation. 
+            ' hence the method is not considered an implementation.
 
             Dim markup =
 <File>

src/Workspaces/SharedUtilitiesAndExtensions/Compiler/VisualBasic/Utilities/CastAnalyzer.vb

@@ -113,10 +113,16 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Extensions
                 Return semanticModel.GetTypeInfo(otherExpression).Type
             End If
 
+            Dim parentSimpleArgument = TryCast(parent, SimpleArgumentSyntax)
+            If TypeOf parentSimpleArgument?.Expression Is CastExpressionSyntax OrElse
+               TypeOf parentSimpleArgument?.Expression Is PredefinedCastExpressionSyntax Then
+                Return semanticModel.GetTypeInfo(parentSimpleArgument.Expression, cancellationToken).Type
+            End If
+
             Return expressionTypeInfo.ConvertedType
         End Function
 
-        Private Shared Function GetSpeculatedExpressionToOuterTypeConversion(speculatedExpression As ExpressionSyntax, speculationAnalyzer As SpeculationAnalyzer, cancellationToken As CancellationToken, <Out> ByRef speculatedExpressionOuterType As ITypeSymbol) As Conversion
+        Private Shared Function GetSpeculatedExpressionToOuterTypeConversion(speculationAnalyzer As SpeculationAnalyzer, speculatedExpression As ExpressionSyntax, outerSpeculatedExpression As ExpressionSyntax, cancellationToken As CancellationToken, <Out> ByRef speculatedExpressionOuterType As ITypeSymbol) As Conversion
             Dim innerSpeculatedExpression = speculatedExpression.WalkDownParentheses()
             Dim typeInfo = speculationAnalyzer.SpeculativeSemanticModel.GetTypeInfo(innerSpeculatedExpression, cancellationToken)
             Dim conv = speculationAnalyzer.SpeculativeSemanticModel.GetConversion(innerSpeculatedExpression, cancellationToken)
@@ -129,7 +135,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Extensions
             speculatedExpression = speculatedExpression.WalkUpParentheses()
             typeInfo = speculationAnalyzer.SpeculativeSemanticModel.GetTypeInfo(speculatedExpression, cancellationToken)
             speculatedExpressionOuterType = GetOuterCastType(speculatedExpression, typeInfo, speculationAnalyzer.SpeculativeSemanticModel, cancellationToken)
-            If speculatedExpressionOuterType Is Nothing Then
+            If speculatedExpressionOuterType Is Nothing OrElse outerSpeculatedExpression.IsParentKind(SyntaxKind.SimpleArgument) Then
                 Return Nothing
             End If
 
@@ -236,7 +242,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Extensions
                 ' Simple case: If the conversion from the inner expression to the cast type is identity,
                 ' the cast can be removed.
                 Return True
-            ElseIf expressionToCastType.IsNarrowing AndAlso expressionToCastType.IsReference
+            ElseIf expressionToCastType.IsNarrowing AndAlso expressionToCastType.IsReference Then
                 ' If the conversion from the inner expression to the cast type is narrowing reference conversion,
                 ' the cast cannot be removed.
                 Return False
@@ -256,7 +262,13 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Extensions
                     speculatedExpressionOuterType = outerType
                     expressionToOuterType = _semanticModel.ClassifyConversion(_castExpressionNode.WalkDownParentheses(), speculatedExpressionOuterType)
                 Else
-                    expressionToOuterType = GetSpeculatedExpressionToOuterTypeConversion(speculationAnalyzer.ReplacedExpression, speculationAnalyzer, _cancellationToken, speculatedExpressionOuterType)
+                    expressionToOuterType = GetSpeculatedExpressionToOuterTypeConversion(speculationAnalyzer, speculationAnalyzer.ReplacedExpression, outerSpeculatedExpression, _cancellationToken, speculatedExpressionOuterType)
+                    If expressionToOuterType = Nothing AndAlso outerSpeculatedExpression.IsParentKind(SyntaxKind.SimpleArgument) Then
+                        ' If we are here we might be inside a SimpleArgument but it is
+                        ' not part of a ParamArray which is handled above.
+                        speculatedExpressionOuterType = outerType
+                        expressionToOuterType = _semanticModel.ClassifyConversion(_castExpressionNode.WalkDownParentheses(), speculatedExpressionOuterType)
+                    End If
                 End If
 
                 ' CONSIDER: Anonymous function conversions cannot be compared from different semantic models as lambda symbol comparison requires syntax tree equality. Should this be a compiler bug?
@@ -266,7 +278,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Extensions
                 End If
 
                 ' If there is an user-defined conversion from the expression to the cast type or the cast
-                ' to the outer type, we need to make sure that the same user-defined conversion will be 
+                ' to the outer type, we need to make sure that the same user-defined conversion will be
                 ' called if the cast is removed.
                 If castToOuterType.IsUserDefined OrElse expressionToCastType.IsUserDefined Then
                     Return (HaveSameUserDefinedConversion(expressionToCastType, expressionToOuterType) OrElse
@@ -287,7 +299,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Extensions
                     Dim expressionToCastTypeIsWideningRefOrDefault As Boolean = expressionToCastType.IsWidening AndAlso (expressionToCastType.IsReference OrElse expressionToCastType.IsDefault)
                     Dim expressionToOuterTypeIsWideningRefOrDefault As Boolean = expressionToOuterType.IsWidening AndAlso (expressionToOuterType.IsReference OrElse expressionToOuterType.IsDefault)
 
-                    If (expressionToCastTypeIsWideningRefOrDefault AndAlso expressionToOuterTypeIsWideningRefOrDefault) Then
+                    If expressionToCastTypeIsWideningRefOrDefault AndAlso expressionToOuterTypeIsWideningRefOrDefault Then
                         If expressionToCastType.IsDefault Then
                             Return Not CastRemovalChangesDefaultValue(castType, outerType)
                         End If
@@ -305,7 +317,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Extensions
                 End If
 
                 If Not castToOuterType.IsValueType AndAlso castToOuterType = expressionToOuterType Then
-                    If (castToOuterType.IsNullableValueType) Then
+                    If castToOuterType.IsNullableValueType Then
                         Return expressionToOuterType.IsWidening AndAlso
                             DirectCast(castExpressionType.OriginalDefinition, ITypeSymbol).SpecialType = SpecialType.System_Nullable_T
                     ElseIf expressionToCastType.IsWidening AndAlso expressionToCastType.IsNumeric AndAlso Not castToOuterType.IsIdentity Then