internal static Expression ComposePropertyNavigation(Expression expression, LambdaExpression filterLambda, bool propagateNull, bool isSingleResult)
{
Expression nullLiteral = ExpressionUtils.NullLiteral;
if (isSingleResult)
{
Expression right = ParameterReplacerVisitor.Replace(filterLambda.Body, filterLambda.Parameters[0], expression);
Expression test = propagateNull ? Expression.AndAlso(Expression.NotEqual(expression, nullLiteral), right) : right;
Expression ifTrue = expression;
Expression ifFalse = Expression.Constant(null, ifTrue.Type);
return(Expression.Condition(test, ifTrue, ifFalse));
}
Type targetType = filterLambda.Parameters[0].Type;
Expression expression7 = expression.EnumerableWhere(filterLambda);
if (propagateNull)
{
Expression expression8 = Expression.Equal(expression, nullLiteral);
Expression expression9 = expression7;
Expression expression10 = ExpressionUtils.EnumerableEmpty(targetType);
return(Expression.Condition(expression8, expression10, expression9, expression10.Type));
}
return(expression7);
}
