Extensions via Extended TypeOf Expressions

Extensions.vb

' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.

Imports System
Imports System.Runtime.CompilerServices
Imports System.Threading
Imports Microsoft.CodeAnalysis
Imports Microsoft.CodeAnalysis.VisualBasic
Imports Microsoft.CodeAnalysis.VisualBasic.Symbols
Imports Microsoft.CodeAnalysis.VisualBasic.Syntax

' This is deliberately declared in the global namespace so that it will always be discoverable (regardless of Imports).
Friend Module Extensions

    ''' <summary>
    ''' This method is provided as a convenience for testing the SemanticModel.GetDeclaredSymbol implementation.
    ''' </summary>
    ''' <param name="node">This parameter will be type checked, and a NotSupportedException will be thrown if the type is not currently supported by an overload of GetDeclaredSymbol.</param>
    <Extension()>
    Friend Function GetDeclaredSymbolFromSyntaxNode(model As SemanticModel, node As SyntaxNode, Optional cancellationToken As CancellationToken = Nothing) As Symbol
        If (Typeof node IsNot AggregationRangeVariableSyntax AndAlso AnonymousObjectCreationExpressionSyntax AndAlso   SimpleImportsClauseSyntax AndAlso
                                        CatchStatementSyntax AndAlso           CollectionRangeVariableSyntax AndAlso             EnumBlockSyntax AndAlso
                                 EnumMemberDeclarationSyntax AndAlso                     EnumStatementSyntax AndAlso            EventBlockSyntax AndAlso
                               ExpressionRangeVariableSyntax AndAlso                  ForEachStatementSyntax AndAlso      FieldInitializerSyntax AndAlso
                                          ForStatementSyntax AndAlso                    LabelStatementSyntax AndAlso            MethodBaseSyntax AndAlso
                                           MethodBlockSyntax AndAlso                ModifiedIdentifierSyntax AndAlso        NamespaceBlockSyntax AndAlso
                                    NamespaceStatementSyntax AndAlso                         ParameterSyntax AndAlso         PropertyBlockSyntax AndAlso
                                     PropertyStatementSyntax AndAlso                         TypeBlockSyntax AndAlso         TypeParameterSyntax AndAlso
                                         TypeStatementSyntax ) _
        Then
            Throw New NotSupportedException("This node type is not supported.")
        End If

        Return DirectCast(model.GetDeclaredSymbol(node, cancellationToken), Symbol)
    End Function

End Module