From 1307608a8c1cbe88a9002a5fd7ee050593d9a2ad Mon Sep 17 00:00:00 2001
From: Joris Van den Bossche <jorisvandenbossche@gmail.com>
Date: Tue, 7 Nov 2023 16:43:42 +0100
Subject: [PATCH] TST: clean-up various tests avoiding CoW issues (#55861)

---
 pandas/tests/frame/indexing/test_indexing.py | 4 ++--
 pandas/tests/frame/test_api.py               | 6 ++----
 pandas/tests/frame/test_nonunique_indexes.py | 4 ++--
 pandas/tests/indexing/test_scalar.py         | 2 +-
 pandas/tests/series/indexing/test_setitem.py | 2 +-
 5 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/pandas/tests/frame/indexing/test_indexing.py b/pandas/tests/frame/indexing/test_indexing.py
index 58581941509e8..4bad0838f7af8 100644
--- a/pandas/tests/frame/indexing/test_indexing.py
+++ b/pandas/tests/frame/indexing/test_indexing.py
@@ -747,11 +747,11 @@ def test_getitem_setitem_float_labels(self, using_array_manager):
         expected = df.iloc[0:2]
         tm.assert_frame_equal(result, expected)
 
-        df.loc[1:2] = 0
+        expected = df.iloc[0:2]
         msg = r"The behavior of obj\[i:j\] with a float-dtype index"
         with tm.assert_produces_warning(FutureWarning, match=msg):
             result = df[1:2]
-        assert (result == 0).all().all()
+        tm.assert_frame_equal(result, expected)
 
         # #2727
         index = Index([1.0, 2.5, 3.5, 4.5, 5.0])
diff --git a/pandas/tests/frame/test_api.py b/pandas/tests/frame/test_api.py
index 5648cb15ef2b4..04821d0865887 100644
--- a/pandas/tests/frame/test_api.py
+++ b/pandas/tests/frame/test_api.py
@@ -217,10 +217,8 @@ def test_with_datetimelikes(self):
 
     def test_deepcopy(self, float_frame):
         cp = deepcopy(float_frame)
-        series = cp["A"]
-        series[:] = 10
-        for idx, value in series.items():
-            assert float_frame["A"][idx] != value
+        cp.loc[0, "A"] = 10
+        assert not float_frame.equals(cp)
 
     def test_inplace_return_self(self):
         # GH 1893
diff --git a/pandas/tests/frame/test_nonunique_indexes.py b/pandas/tests/frame/test_nonunique_indexes.py
index 12aeede2560b8..34f172e900ab7 100644
--- a/pandas/tests/frame/test_nonunique_indexes.py
+++ b/pandas/tests/frame/test_nonunique_indexes.py
@@ -322,7 +322,7 @@ def test_set_value_by_index(self):
 
         df = DataFrame(np.arange(9).reshape(3, 3).T)
         df.columns = list("AAA")
-        expected = df.iloc[:, 2]
+        expected = df.iloc[:, 2].copy()
 
         with tm.assert_produces_warning(warn, match=msg):
             df.iloc[:, 0] = 3
@@ -330,7 +330,7 @@ def test_set_value_by_index(self):
 
         df = DataFrame(np.arange(9).reshape(3, 3).T)
         df.columns = [2, float(2), str(2)]
-        expected = df.iloc[:, 1]
+        expected = df.iloc[:, 1].copy()
 
         with tm.assert_produces_warning(warn, match=msg):
             df.iloc[:, 0] = 3
diff --git a/pandas/tests/indexing/test_scalar.py b/pandas/tests/indexing/test_scalar.py
index 2753b3574e583..5b95eb65ff00a 100644
--- a/pandas/tests/indexing/test_scalar.py
+++ b/pandas/tests/indexing/test_scalar.py
@@ -140,7 +140,7 @@ def test_frame_at_with_duplicate_axes(self):
         df = DataFrame(arr, columns=["A", "A"])
 
         result = df.at[0, "A"]
-        expected = df.iloc[0]
+        expected = df.iloc[0].copy()
 
         tm.assert_series_equal(result, expected)
 
diff --git a/pandas/tests/series/indexing/test_setitem.py b/pandas/tests/series/indexing/test_setitem.py
index 5fcd3a19dcaa4..16c127e6ece7b 100644
--- a/pandas/tests/series/indexing/test_setitem.py
+++ b/pandas/tests/series/indexing/test_setitem.py
@@ -1746,7 +1746,7 @@ def test_setitem_with_bool_indexer():
     # GH#42530
 
     df = DataFrame({"a": [1, 2, 3], "b": [4, 5, 6]})
-    result = df.pop("b")
+    result = df.pop("b").copy()
     result[[True, False, False]] = 9
     expected = Series(data=[9, 5, 6], name="b")
     tm.assert_series_equal(result, expected)