one more

Author: MarcoGorelli

pandas/tests/frame/indexing/test_mask.py

@@ -145,7 +145,7 @@ def test_mask_return_dtype():
 
 def test_mask_inplace_no_other():
     # GH#51685
-    df = DataFrame({"a": [1, 2], "b": ["x", "y"]})
+    df = DataFrame({"a": [1.0, 2.0], "b": ["x", "y"]})
     cond = DataFrame({"a": [True, False], "b": [False, True]})
     df.mask(cond, inplace=True)
     expected = DataFrame({"a": [np.nan, 2], "b": ["x", np.nan]})

pandas/tests/frame/indexing/test_setitem.py

@@ -987,7 +987,9 @@ def test_setitem_other_callable(self):
         def inc(x):
             return x + 1
 
-        df = DataFrame([[-1, 1], [1, -1]])
+        # Set dtype object straight away to avoid upcast when setting
+        # inc below
+        df = DataFrame([[-1, 1], [1, -1]], dtype=object)
         df[df > 0] = inc
 
         expected = DataFrame([[-1, inc], [inc, -1]])

pandas/tests/frame/methods/test_asof.py

@@ -79,7 +79,8 @@ def test_missing(self, date_range_frame):
         # GH 15118
         # no match found - `where` value before earliest date in index
         N = 10
-        df = date_range_frame.iloc[:N].copy()
+        # Cast to 'float64' to avoid upcast when introducing nan in df.asof
+        df = date_range_frame.iloc[:N].copy().astype("float64")
 
         result = df.asof("1989-12-31")