Function test_order_by

python/pyarrow/tests/test_acero.py:266–300

()

def test_order_by():
    table = pa.table({'a': [1, 2, 3, 4], 'b': [1, 3, None, 2]})
    table_source = Declaration("table_source", TableSourceNodeOptions(table))

    ord_opts = OrderByNodeOptions([("b", "ascending")])
    decl = Declaration.from_sequence([table_source, Declaration("order_by", ord_opts)])
    result = decl.to_table()
    expected = pa.table({"a": [1, 4, 2, 3], "b": [1, 2, 3, None]})
    assert result.equals(expected)

    ord_opts = OrderByNodeOptions([(field("b"), "descending")])
    decl = Declaration.from_sequence([table_source, Declaration("order_by", ord_opts)])
    result = decl.to_table()
    expected = pa.table({"a": [2, 4, 1, 3], "b": [3, 2, 1, None]})
    assert result.equals(expected)

    ord_opts = OrderByNodeOptions([(1, "descending")], null_placement="at_start")
    decl = Declaration.from_sequence([table_source, Declaration("order_by", ord_opts)])
    result = decl.to_table()
    expected = pa.table({"a": [3, 2, 4, 1], "b": [None, 3, 2, 1]})
    assert result.equals(expected)

    # empty ordering
    ord_opts = OrderByNodeOptions([])
    decl = Declaration.from_sequence([table_source, Declaration("order_by", ord_opts)])
    with pytest.raises(
        ValueError, match="`ordering` must be an explicit non-empty ordering"
    ):
        _ = decl.to_table()

    with pytest.raises(ValueError, match="\"decreasing\" is not a valid sort order"):
        _ = OrderByNodeOptions([("b", "decreasing")])

    with pytest.raises(ValueError, match="\"start\" is not a valid null placement"):
        _ = OrderByNodeOptions([("b", "ascending")], null_placement="start")


def test_hash_join():