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VB -> C#: InvalidOperationException caused by LINQ GroupBy with multiple properties

Aberta
  • Algo errado?
#1,014 1 comentário 0 reações 0 responsáveis Ver no GitHub

Ninguém assumiu esta issue ainda.

Avaliação

Dificuldade
3/5
Tempo estimado
1-2 dias
Facilidade para iniciantes
35/100
Tipo de issue
Bug
Clareza
Razoavelmente clara
Status de atividade
Estagnada
Stack de tecnologia
csharp
Domínio
tooling

Direção de pesquisa

Comece pelo stack trace de QueryConverter na issue e reproduza a consulta VB LINQ usando várias propriedades GroupBy. Rastreie a conversão da subconsulta e do segmento de consulta envolvidos na falha. A tarefa estará concluída quando a reprodução for convertida sem InvalidOperationException e produzir C# válido para a consulta agrupada.

Escrita pelo modelo de indexação a partir do texto da issue.

Descrição

VB -> C#
VB.Net input code
Public Class ConversionTest4
    Private Class MyEntity
        Property FavoriteNumber As Integer
        Property FavoriteColor As String
        Property Name As String
    End Class
    Private Sub BugRepro()

        Dim entities As New List(Of MyEntity)

        Dim result As IEnumerable(Of String) = From e In entities
                                               Group e By e.FavoriteNumber, e.FavoriteColor Into g1 = Group
                                               Select g1.FirstOrDefault().Name

    End Sub
End Class
Erroneous output
public class ConversionTest4
    {
        private class MyEntity
        {
            public int FavoriteNumber { get; set; }
            public string FavoriteColor { get; set; }
            public string Name { get; set; }
        }
        private void BugRepro()
        {

            var entities = new List<MyEntity>();

            var result = default
#error Cannot convert QueryExpressionSyntax - see comment for details
        /* Cannot convert QueryExpressionSyntax, System.InvalidOperationException: Sequence contains more than one element
            at System.Linq.Enumerable.Single[TSource](IEnumerable`1 source)
            at ICSharpCode.CodeConverter.CSharp.QueryConverter.<ConvertSubQueryAsync>d__15.MoveNext()
         --- End of stack trace from previous location where exception was thrown ---
            at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
            at ICSharpCode.CodeConverter.CSharp.QueryConverter.<ConvertQueryWithContinuationAsync>d__14.MoveNext()
         --- End of stack trace from previous location where exception was thrown ---
            at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
            at ICSharpCode.CodeConverter.CSharp.QueryConverter.<ConvertQuerySegmentsAsync>d__12.MoveNext()
         --- End of stack trace from previous location where exception was thrown ---
            at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
            at ICSharpCode.CodeConverter.CSharp.QueryConverter.<ConvertClausesAsync>d__7.MoveNext()
         --- End of stack trace from previous location where exception was thrown ---
            at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
            at ICSharpCode.CodeConverter.CSharp.ExpressionNodeVisitor.<VisitQueryExpression>d__68.MoveNext()
         --- End of stack trace from previous location where exception was thrown ---
            at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
            at ICSharpCode.CodeConverter.CSharp.CommentConvertingVisitorWrapper.<ConvertHandledAsync>d__8`1.MoveNext()

         Input:
         From e In entities
                                                        Group e By e.FavoriteNumber, e.FavoriteColor Into g1 = Group
                                                        Select g1.FirstOrDefault().Name

          */;

        }
    }
Details
  • Product in use: VS extension
  • Version in use: 9.2.2.0
  • This is a simplified repro code
  • I believe this exception happens because the "Group e By" line contains multiple properties to group on.
Linguagem predominante
C#
Estrelas
913
Forks
243
Nenhum PR com merge em 30d

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