From be66fde4162cd50307d985316f1897dc789cbd95 Mon Sep 17 00:00:00 2001
From: Matthew Roeschke <10647082+mroeschke@users.noreply.github.com>
Date: Wed, 5 Jun 2024 14:34:01 -0700
Subject: [PATCH] Add test verifying copy

---
 python/cudf/cudf/core/indexed_frame.py | 2 +-
 python/cudf/cudf/tests/test_series.py  | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/python/cudf/cudf/core/indexed_frame.py b/python/cudf/cudf/core/indexed_frame.py
index 1e27bcda4fc..d898eb4b9c3 100644
--- a/python/cudf/cudf/core/indexed_frame.py
+++ b/python/cudf/cudf/core/indexed_frame.py
@@ -1917,7 +1917,7 @@ def nans_to_nulls(self):
             converted = col.nans_to_nulls()
             if converted is col:
                 converted = converted.copy()
-            result.append(col)
+            result.append(converted)
         return self._from_data_like_self(
             self._data._from_columns_like_self(result)
         )
diff --git a/python/cudf/cudf/tests/test_series.py b/python/cudf/cudf/tests/test_series.py
index 323716d5fc3..f47c42d9a1d 100644
--- a/python/cudf/cudf/tests/test_series.py
+++ b/python/cudf/cudf/tests/test_series.py
@@ -2841,3 +2841,10 @@ def test_series_from_series_index_no_shallow_copy():
     ser1 = cudf.Series(range(3), index=list("abc"))
     ser2 = cudf.Series(ser1)
     assert ser1.index is ser2.index
+
+
+@pytest.mark.parametrize("value", [1, 1.1])
+def test_nans_to_nulls_noop_copies_column(value):
+    ser1 = cudf.Series([value])
+    ser2 = ser1.nans_to_nulls()
+    assert ser1._column is not ser2._column