def _build_sort_expression(
sort_field: Union[FieldProxy, SortExpression]
) -> SortExpression:
return (
SortExpression({+sort_field: 1})
if not isinstance(sort_field, SortExpression)
else sort_field
)
def _validate_sort_argument(cls, sort: Any) -> Optional[SortExpression]:
if sort is None:
return None
if isinstance(sort, tuple):
for sorted_field in sort:
if not isinstance(sorted_field, (FieldProxy, SortExpression)):
raise TypeError(
"sort elements have to be Model fields or asc, desc descriptors"
)
sort_expression: Dict = {}
for sort_field in sort:
sort_expression.update(cls._build_sort_expression(sort_field))
return SortExpression(sort_expression)
if not isinstance(sort, (FieldProxy, SortExpression)):
raise TypeError("sort has to be a Model field or "
"asc, desc descriptors or a tuple of these")
return cls._build_sort_expression(sort)
def test_sort_empty_repr():
assert repr(SortExpression()) == "SortExpression()"