client_and_types = (, )
project_id = 'precise-truck-742'
def test_read_rows_to_arrow(client_and_types, project_id):
    client, types = client_and_types
    read_session = types.ReadSession()
    read_session.table = "projects/{}/datasets/{}/tables/{}".format(
        "bigquery-public-data", "new_york_citibike", "citibike_stations"
    )

    read_session.read_options.selected_fields.append("station_id")
    read_session.read_options.selected_fields.append("latitude")
    read_session.read_options.selected_fields.append("longitude")
    read_session.read_options.selected_fields.append("name")
    read_session.data_format = types.DataFormat.ARROW

    session = client.create_read_session(
        request={
            "parent": "projects/{}".format(project_id),
            "read_session": read_session,
            "max_stream_count": 1,
        }
    )

    assert len(session.streams) == 1

    streamname = session.streams[0].name

    tbl = client.read_rows(streamname, offset=0).to_arrow(session)

    assert tbl.num_columns == 4
    schema = tbl.schema
    # Use field with a name specifier as there may be ordering differences
    # when selected_fields is used


  assert pyarrow.types.is_int64(schema.field("station_id").type)


E       AssertionError: assert False

E        +  where False = <function is_int64 at 0x7f31609b7310>(DataType(string))

E        +    where <function is_int64 at 0x7f31609b7310> = <module 'pyarrow.types' from '/tmpfs/src/github/python-bigquery-storage/.nox/prerelease_deps-3-8/lib/python3.8/site-packages/pyarrow/types.py'>.is_int64

E        +      where <module 'pyarrow.types' from '/tmpfs/src/github/python-bigquery-storage/.nox/prerelease_deps-3-8/lib/python3.8/site-packages/pyarrow/types.py'> = pyarrow.types

E        +    and   DataType(string) = pyarrow.Field<station_id: string not null>.type

E        +      where pyarrow.Field<station_id: string not null> = <built-in method field of pyarrow.lib.Schema object at 0x7f315cb06f30>('station_id')

E        +        where <built-in method field of pyarrow.lib.Schema object at 0x7f315cb06f30> = station_id: string not null\n  -- field metadata --\n  description: 'Unique identifier of a station.'\nname: string\n  -- field metadata --\n  description: 'Public name of the station.'\nlatitude: double\n  -- field metadata --\n  description: 'The latitude of station. The field value must be a valid ' + 42\nlongitude: double\n  -- field metadata --\n  description: 'The longitude of station. The field value must be a valid' + 43.field
tests/system/reader/test_reader_dataframe.py:54: AssertionError