From 76e8f245eecf4f3516d80b0efe7367a00f548efa Mon Sep 17 00:00:00 2001 From: Yuanhao Geng <41546976+GYHHAHA@users.noreply.github.com> Date: Thu, 14 Jul 2022 02:26:48 -0500 Subject: [PATCH] Update test_groupby_dropna.py --- pandas/tests/groupby/test_groupby_dropna.py | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/pandas/tests/groupby/test_groupby_dropna.py b/pandas/tests/groupby/test_groupby_dropna.py index ca55263146db3..515c96780e731 100644 --- a/pandas/tests/groupby/test_groupby_dropna.py +++ b/pandas/tests/groupby/test_groupby_dropna.py @@ -378,3 +378,12 @@ def test_groupby_nan_included(): tm.assert_numpy_array_equal(result_values, expected_values) assert np.isnan(list(result.keys())[2]) assert list(result.keys())[0:2] == ["g1", "g2"] + + +def test_groupby_drop_nan_with_multi_index(): + # GH 39895 + df = pd.DataFrame([[np.nan, 0, 1]], columns=["a", "b", "c"]) + df = df.set_index(["a", "b"]) + result = df.groupby(["a", "b"], dropna=False).first() + expected = df + tm.assert_frame_equal(result, expected)