avoid dtype inference warnings by removing explicit dtype=object

Author: jorisvandenbossche

pandas/tests/dtypes/test_missing.py

@@ -131,7 +131,7 @@ def test_isna_isnull(self, isna_f):
         [
             np.arange(4, dtype=float),
             [0.0, 1.0, 0.0, 1.0],
-            Series(list("abcd"), dtype=object),
+            Series(list("abcd")),
             date_range("2020-01-01", periods=4),
         ],
     )

pandas/tests/frame/methods/test_set_index.py

@@ -158,8 +158,8 @@ def test_set_index(self, float_string_frame):
     def test_set_index_names(self):
         df = DataFrame(
             np.ones((10, 4)),
-            columns=Index(list("ABCD"), dtype=object),
-            index=Index([f"i-{i}" for i in range(10)], dtype=object),
+            columns=Index(list("ABCD")),
+            index=Index([f"i-{i}" for i in range(10)]),
         )
         df.index.name = "name"
 

pandas/tests/series/indexing/test_getitem.py

@@ -360,7 +360,7 @@ def test_getitem_no_matches(self, box):
         # GH#33462 we expect the same behavior for list/ndarray/Index/Series
         ser = Series(["A", "B"])
 
-        key = Series(["C"], dtype=object)
+        key = Series(["C"])
         key = box(key)
 
         msg = r"None of \[Index\(\['C'\], dtype='object|str'\)\] are in the \[index\]"