import pytest import pandas as pd from pandas.tests.extension.list.array import ( ListArray, ListDtype, make_data, ) @pytest.fixture def dtype(): return ListDtype() @pytest.fixture def data(): """Length-100 ListArray for semantics test.""" data = make_data() while len(data[0]) == len(data[1]): data = make_data() return ListArray(data) def test_to_csv(data): # https://github.com/pandas-dev/pandas/issues/28840 # array with list-likes fail when doing astype(str) on the numpy array # which was done in get_values_for_csv df = pd.DataFrame({"a": data}) res = df.to_csv() assert str(data[0]) in res