don't hardcode object dtype

Author: jorisvandenbossche

pandas/tests/io/test_feather.py

@@ -136,17 +136,17 @@ def test_rw_use_threads(self):
     def test_path_pathlib(self):
         df = pd.DataFrame(
             1.1 * np.arange(120).reshape((30, 4)),
-            columns=pd.Index(list("ABCD"), dtype=object),
-            index=pd.Index([f"i-{i}" for i in range(30)], dtype=object),
+            columns=pd.Index(list("ABCD")),
+            index=pd.Index([f"i-{i}" for i in range(30)]),
         ).reset_index()
         result = tm.round_trip_pathlib(df.to_feather, read_feather)
         tm.assert_frame_equal(df, result)
 
     def test_path_localpath(self):
         df = pd.DataFrame(
             1.1 * np.arange(120).reshape((30, 4)),
-            columns=pd.Index(list("ABCD"), dtype=object),
-            index=pd.Index([f"i-{i}" for i in range(30)], dtype=object),
+            columns=pd.Index(list("ABCD")),
+            index=pd.Index([f"i-{i}" for i in range(30)]),
         ).reset_index()
         result = tm.round_trip_localpath(df.to_feather, read_feather)
         tm.assert_frame_equal(df, result)

pandas/tests/io/test_parquet.py

@@ -111,10 +111,7 @@ def fp(request):
 
 @pytest.fixture
 def df_compat():
-    # TODO(infer_string) should this give str columns?
-    return pd.DataFrame(
-        {"A": [1, 2, 3], "B": "foo"}, columns=pd.Index(["A", "B"], dtype=object)
-    )
+    return pd.DataFrame({"A": [1, 2, 3], "B": "foo"}, columns=pd.Index(["A", "B"]))
 
 
 @pytest.fixture