Add unit tests for tm.shares_memory (#55372)

Author: Aniketsy

pandas/tests/util/test_shares_memory.py

@@ -30,3 +30,42 @@ def test_shares_memory_string():
 
     obj = pd.array(["a", "b"], dtype=pd.ArrowDtype(pa.string()))
     assert tm.shares_memory(obj, obj)
+
+
+# Unit tests for tm.shares_memory (#55372)
+def test_shares_memory_numpy():
+    arr = np.arange(10)
+    view = arr[:5]
+    assert tm.shares_memory(arr, view)
+    arr2 = np.arange(10)
+    assert not tm.shares_memory(arr, arr2)
+
+
+def test_shares_memory_series():
+    arr = np.arange(10)
+    s = pd.Series(arr)
+    assert tm.shares_memory(arr, s)
+    s2 = pd.Series(np.arange(10))
+    assert not tm.shares_memory(s, s2)
+
+
+def test_shares_memory_dataframe_single_block():
+    arr = np.arange(10)
+    df = pd.DataFrame({"a": arr})
+    assert tm.shares_memory(arr, df)
+    df2 = pd.DataFrame({"a": np.arange(10)})
+    assert not tm.shares_memory(df, df2)
+
+
+def test_shares_memory_rangeindex():
+    idx = pd.RangeIndex(10)
+    arr = np.arange(10)
+    assert not tm.shares_memory(idx, arr)
+
+
+def test_shares_memory_multiindex():
+    idx = pd.MultiIndex.from_arrays([np.arange(10), np.arange(10, 20)])
+    arr = idx.codes[0]
+    assert tm.shares_memory(idx, arr)
+    arr2 = np.arange(10)
+    assert not tm.shares_memory(idx, arr2)