private Expression TranslateGroupingKey(Expression expression)
{
switch (expression)
{
case NewExpression newExpression:
if (newExpression.Arguments.Count == 0)
{
return(newExpression);
}
var newArguments = new Expression[newExpression.Arguments.Count];
for (var i = 0; i < newArguments.Length; i++)
{
newArguments[i] = TranslateGroupingKey(newExpression.Arguments[i]);
if (newArguments[i] == null)
{
return(null);
}
}
return(newExpression.Update(newArguments));
case MemberInitExpression memberInitExpression:
var updatedNewExpression = (NewExpression)TranslateGroupingKey(memberInitExpression.NewExpression);
if (updatedNewExpression == null)
{
return(null);
}
var newBindings = new MemberAssignment[memberInitExpression.Bindings.Count];
for (var i = 0; i < newBindings.Length; i++)
{
var memberAssignment = (MemberAssignment)memberInitExpression.Bindings[i];
var visitedExpression = TranslateGroupingKey(memberAssignment.Expression);
if (visitedExpression == null)
{
return(null);
}
newBindings[i] = memberAssignment.Update(visitedExpression);
}
return(memberInitExpression.Update(updatedNewExpression, newBindings));
default:
var translation = _expressionTranslator.Translate(expression);
if (translation == null)
{
return(null);
}
return(translation.Type == expression.Type
? (Expression)translation
: Expression.Convert(translation, expression.Type));
}
}
public override Expression Visit(Expression expression)
{
if (expression == null)
{
return(null);
}
if (!(expression is NewExpression ||
expression is MemberInitExpression ||
expression is EntityShaperExpression ||
expression is IncludeExpression))
{
// This skips the group parameter from GroupJoin
if (expression is ParameterExpression parameter &&
parameter.Type.IsGenericType &&
parameter.Type.GetGenericTypeDefinition() == typeof(IEnumerable <>))
{
return(parameter);
}
if (_clientEval)
{
switch (expression)
{
case ConstantExpression _:
return(expression);
case MaterializeCollectionNavigationExpression materializeCollectionNavigationExpression:
return(AddCollectionProjection(
_queryableMethodTranslatingExpressionVisitor.TranslateSubquery(
materializeCollectionNavigationExpression.Subquery),
materializeCollectionNavigationExpression.Navigation,
null));
case MethodCallExpression methodCallExpression:
{
if (methodCallExpression.Method.IsGenericMethod &&
methodCallExpression.Method.DeclaringType == typeof(Enumerable) &&
methodCallExpression.Method.Name == nameof(Enumerable.ToList))
{
return(AddCollectionProjection(
_queryableMethodTranslatingExpressionVisitor.TranslateSubquery(
methodCallExpression.Arguments[0]),
null,
methodCallExpression.Method.GetGenericArguments()[0]));
}
var subquery = _queryableMethodTranslatingExpressionVisitor.TranslateSubquery(methodCallExpression);
if (subquery != null)
{
if (subquery.ResultCardinality == ResultCardinality.Enumerable)
{
return(AddCollectionProjection(subquery, null, subquery.ShaperExpression.Type));
}
return(new SingleResultShaperExpression(
new ProjectionBindingExpression(
_queryExpression,
_queryExpression.AddSubqueryProjection(subquery, out var innerShaper),
typeof(ValueBuffer)),
innerShaper,
subquery.ShaperExpression.Type));
}
break;
}
}
var translation = _expressionTranslatingExpressionVisitor.Translate(expression);
if (translation == null)
{
return(base.Visit(expression));
}
if (translation.Type != expression.Type)
{
translation = NullSafeConvert(translation, expression.Type);
}
return(new ProjectionBindingExpression(_queryExpression, _queryExpression.AddToProjection(translation), expression.Type));
}
else
{
var translation = _expressionTranslatingExpressionVisitor.Translate(expression);
if (translation == null)
{
return(null);
}
if (translation.Type != expression.Type)
{
translation = NullSafeConvert(translation, expression.Type);
}
_projectionMapping[_projectionMembers.Peek()] = translation;
return(new ProjectionBindingExpression(_queryExpression, _projectionMembers.Peek(), expression.Type));
}
}
return(base.Visit(expression));
}
