' Licensed to the .NET Foundation under one or more agreements.
' The .NET Foundation licenses this file to you under the MIT license.
' See the LICENSE file in the project root for more information.
 
Imports System.Collections.Immutable
Imports System.Composition
Imports System.Diagnostics.CodeAnalysis
Imports Microsoft.CodeAnalysis.CodeFixes
Imports Microsoft.CodeAnalysis.Editing
Imports Microsoft.CodeAnalysis.RemoveAsyncModifier
Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
 
Namespace Microsoft.CodeAnalysis.VisualBasic.RemoveAsyncModifier
    <ExportCodeFixProvider(LanguageNames.VisualBasic, Name:=PredefinedCodeFixProviderNames.RemoveAsyncModifier), [Shared]>
    <ExtensionOrder(After:=PredefinedCodeFixProviderNames.MakeMethodSynchronous)>
    Friend Class VisualBasicRemoveAsyncModifierCodeFixProvider
        Inherits AbstractRemoveAsyncModifierCodeFixProvider(Of ReturnStatementSyntax, ExpressionSyntax)
 
        Private Const BC42356 As String = NameOf(BC42356) ' This async method lacks 'Await' operators and so will run synchronously.
 
        Private Shared ReadOnly s_diagnosticIds As ImmutableArray(Of String) = ImmutableArray.Create(BC42356)
 
        <ImportingConstructor>
        <SuppressMessage("RoslynDiagnosticsReliability", "RS0033:Importing constructor should be [Obsolete]", Justification:="Used in test code: https://github.com/dotnet/roslyn/issues/42814")>
        Public Sub New()
        End Sub
 
        Public Overrides ReadOnly Property FixableDiagnosticIds As ImmutableArray(Of String) = s_diagnosticIds
 
        Protected Overrides Function IsAsyncSupportingFunctionSyntax(node As SyntaxNode) As Boolean
            Return node.IsAsyncSupportedFunctionSyntax()
        End Function
 
        Protected Overrides Function RemoveAsyncModifier(generator As SyntaxGenerator, methodLikeNode As SyntaxNode) As SyntaxNode
            Dim methodBlock = TryCast(methodLikeNode, MethodBlockSyntax)
            If methodBlock IsNot Nothing Then
                Dim subOrFunctionStatement = methodBlock.SubOrFunctionStatement
                Dim newSubOrFunctionStatement = RemoveAsyncModifierHelpers.RemoveAsyncKeyword(subOrFunctionStatement)
                Return methodBlock.WithSubOrFunctionStatement(newSubOrFunctionStatement)
            End If
 
            Dim multiLineLambda = TryCast(methodLikeNode, MultiLineLambdaExpressionSyntax)
            If multiLineLambda IsNot Nothing Then
                Return RemoveAsyncModifierHelpers.FixMultiLineLambdaExpression(multiLineLambda)
            End If
 
            Dim singleLineLambda = TryCast(methodLikeNode, SingleLineLambdaExpressionSyntax)
            If singleLineLambda IsNot Nothing Then
                Return RemoveAsyncModifierHelpers.FixSingleLineLambdaExpression(singleLineLambda)
            End If
 
            Return Nothing
        End Function
 
        Protected Overrides Function ConvertToBlockBody(node As SyntaxNode, expressionBody As ExpressionSyntax) As SyntaxNode
            Throw ExceptionUtilities.Unreachable
        End Function
    End Class
End Namespace