public void Can_replace_QueryableDefaultIfEmpty_method()
{
var baseQuery = new List <TestSubject>().AsQueryable();
var query = baseQuery.DefaultIfEmpty();
var visitor = new DefaultIfEmptyRewriter();
var expression = visitor.Visit(query.Expression);
var call = Assert.IsAssignableFrom <MethodCallExpression>(expression);
Assert.Equal("DefaultIfEmpty", call.Method.Name);
Assert.Equal(2, call.Arguments.Count);
}
public void Can_provide_default_value()
{
var baseQuery = new List <TestSubject>().AsQueryable();
var query = baseQuery.DefaultIfEmpty();
var visitor = new DefaultIfEmptyRewriter();
var expression = visitor.Visit(query.Expression);
var call = Assert.IsAssignableFrom <MethodCallExpression>(expression);
Assert.Equal("DefaultIfEmpty", call.Method.Name);
var constant = Assert.IsAssignableFrom <ConstantExpression>(call.Arguments[1]);
Assert.IsType <TestSubject>(constant.Value);
}
public void Can_replace_EnumerableDefaultIfEmpty_method()
{
var baseQuery = new List <TestSubject>().AsQueryable();
var query = from x in baseQuery
join y in baseQuery on x.Id equals y.ParentId into z
from q in z.DefaultIfEmpty()
select new { x.Name, ParentName = q.Name };
var visitor = new DefaultIfEmptyRewriter();
var expression = visitor.Visit(query.Expression);
var selectMany = (MethodCallExpression)expression;
var call = ((MethodCallExpression)((LambdaExpression)((UnaryExpression)selectMany.Arguments[1]).Operand).Body);
Assert.Equal("DefaultIfEmpty", call.Method.Name);
Assert.Equal(2, call.Arguments.Count);
}