internal override Expression VisitMemberAccess(MemberExpression m)
{
if (MetaPosition.AreSameMember(m.Member, association.ThisMember.Member))
{
var keyValues = GetKeyValues(Visit(m.Expression), association.ThisKey);
return(WhereClauseFromSourceAndKeys(otherSouce, association.OtherKey.ToArray(), keyValues));
}
var expression = Visit(m.Expression);
if (expression != m.Expression)
{
if (expression.Type != m.Expression.Type && m.Member.Name == "Count" && TypeSystem.IsSequenceType(expression.Type))
{
return(Expression.Call(typeof(Enumerable), "Count", new Type[1]
{
TypeSystem.GetElementType(expression.Type)
}, expression));
}
return(Expression.MakeMemberAccess(expression, m.Member));
}
return(m);
}
internal static Expression WhereClauseFromSourceAndKeys(Expression source, MetaDataMember[] keyMembers, Expression[] keyValues)
{
var elementType = TypeSystem.GetElementType(source.Type);
var parameterExpression = Expression.Parameter(elementType, "p");
Expression expression = null;
for (var i = 0; i < keyMembers.Length; i++)
{
var metaDataMember = keyMembers[i];
var expression2 = (elementType == metaDataMember.Member.DeclaringType) ? parameterExpression : ((Expression)Expression.Convert(parameterExpression, metaDataMember.Member.DeclaringType));
Expression expression3 = (metaDataMember.Member is FieldInfo) ? Expression.Field(expression2, (FieldInfo)metaDataMember.Member) : Expression.Property(expression2, (PropertyInfo)metaDataMember.Member);
var expression4 = keyValues[i];
if (expression4.Type != expression3.Type)
{
expression4 = Expression.Convert(expression4, expression3.Type);
}
Expression expression5 = Expression.Equal(expression3, expression4);
expression = ((expression != null) ? Expression.And(expression, expression5) : expression5);
}
return(Expression.Call(typeof(Enumerable), "Where", new Type[1]
{
parameterExpression.Type
}, source, Expression.Lambda(expression, parameterExpression)));
}
internal override SqlNode Visit(SqlNode node)
{
if (node == null)
{
return(null);
}
sourceExpression = node as SqlExpression;
if (sourceExpression != null)
{
Type type = sourceExpression.ClrType;
UnwrapStack unwrap = this.UnwrapSequences;
while (unwrap != null)
{
if (unwrap.Unwrap)
{
type = TypeSystem.GetElementType(type);
}
unwrap = unwrap.Last;
}
sourceType = type;
}
if (sourceType != null && TypeSystem.GetNonNullableType(sourceType).IsValueType)
{
return(node); // Value types can't also have a dynamic type.
}
if (sourceType != null && TypeSystem.HasIEnumerable(sourceType))
{
return(node); // Sequences can't be polymorphic.
}
switch (node.NodeType)
{
case SqlNodeType.ScalarSubSelect:
case SqlNodeType.Multiset:
case SqlNodeType.Element:
case SqlNodeType.SearchedCase:
case SqlNodeType.ClientCase:
case SqlNodeType.SimpleCase:
case SqlNodeType.Member:
case SqlNodeType.DiscriminatedType:
case SqlNodeType.New:
case SqlNodeType.FunctionCall:
case SqlNodeType.MethodCall:
case SqlNodeType.Convert: // Object identity does not survive convert. It does survive Cast.
// Dig no further.
return(node);
case SqlNodeType.TypeCase:
sourceType = ((SqlTypeCase)node).RowType.Type;
return(node);
case SqlNodeType.Link:
sourceType = ((SqlLink)node).RowType.Type;
return(node);
case SqlNodeType.Table:
sourceType = ((SqlTable)node).RowType.Type;
return(node);
case SqlNodeType.Value:
SqlValue val = (SqlValue)node;
if (val.Value != null)
{
// In some cases the ClrType of a Value node may
// differ from the actual runtime type of the value.
// Therefore, we ensure here that the correct type is set.
sourceType = val.Value.GetType();
}
return(node);
}
return(base.Visit(node));
}