fix compute / feather tests

python/pyarrow/tests/test_compute.py

@@ -1020,7 +1020,7 @@ def test_replace_slice():
     offsets = range(-3, 4)
 
     arr = pa.array([None, '', 'a', 'ab', 'abc', 'abcd', 'abcde'])
-    series = arr.to_pandas()
+    series = arr.to_pandas().astype(object).replace({np.nan: None})
     for start in offsets:
         for stop in offsets:
             expected = series.str.slice_replace(start, stop, 'XX')
@@ -1031,7 +1031,7 @@ def test_replace_slice():
             assert pc.binary_replace_slice(arr, start, stop, 'XX') == actual
 
     arr = pa.array([None, '', 'π', 'πb', 'πbθ', 'πbθd', 'πbθde'])
-    series = arr.to_pandas()
+    series = arr.to_pandas().astype(object).replace({np.nan: None})
     for start in offsets:
         for stop in offsets:
             expected = series.str.slice_replace(start, stop, 'XX')
@@ -2125,50 +2125,51 @@ def test_strftime():
             for fmt in formats:
                 options = pc.StrftimeOptions(fmt)
                 result = pc.strftime(tsa, options=options)
-                expected = pa.array(ts.strftime(fmt))
+                # cast to the same type as result to ignore string vs large_string
+                expected = pa.array(ts.strftime(fmt)).cast(result.type)
                 assert result.equals(expected)
 
         fmt = "%Y-%m-%dT%H:%M:%S"
 
         # Default format
         tsa = pa.array(ts, type=pa.timestamp("s", timezone))
         result = pc.strftime(tsa, options=pc.StrftimeOptions())
-        expected = pa.array(ts.strftime(fmt))
+        expected = pa.array(ts.strftime(fmt)).cast(result.type)
         assert result.equals(expected)
 
         # Default format plus timezone
         tsa = pa.array(ts, type=pa.timestamp("s", timezone))
         result = pc.strftime(tsa, options=pc.StrftimeOptions(fmt + "%Z"))
-        expected = pa.array(ts.strftime(fmt + "%Z"))
+        expected = pa.array(ts.strftime(fmt + "%Z")).cast(result.type)
         assert result.equals(expected)
 
         # Pandas %S is equivalent to %S in arrow for unit="s"
         tsa = pa.array(ts, type=pa.timestamp("s", timezone))
         options = pc.StrftimeOptions("%S")
         result = pc.strftime(tsa, options=options)
-        expected = pa.array(ts.strftime("%S"))
+        expected = pa.array(ts.strftime("%S")).cast(result.type)
         assert result.equals(expected)
 
         # Pandas %S.%f is equivalent to %S in arrow for unit="us"
         tsa = pa.array(ts, type=pa.timestamp("us", timezone))
         options = pc.StrftimeOptions("%S")
         result = pc.strftime(tsa, options=options)
-        expected = pa.array(ts.strftime("%S.%f"))
+        expected = pa.array(ts.strftime("%S.%f")).cast(result.type)
         assert result.equals(expected)
 
         # Test setting locale
         tsa = pa.array(ts, type=pa.timestamp("s", timezone))
         options = pc.StrftimeOptions(fmt, locale="C")
         result = pc.strftime(tsa, options=options)
-        expected = pa.array(ts.strftime(fmt))
+        expected = pa.array(ts.strftime(fmt)).cast(result.type)
         assert result.equals(expected)
 
     # Test timestamps without timezone
     fmt = "%Y-%m-%dT%H:%M:%S"
     ts = pd.to_datetime(times)
     tsa = pa.array(ts, type=pa.timestamp("s"))
     result = pc.strftime(tsa, options=pc.StrftimeOptions(fmt))
-    expected = pa.array(ts.strftime(fmt))
+    expected = pa.array(ts.strftime(fmt)).cast(result.type)
 
     # Positional format
     assert pc.strftime(tsa, fmt) == result

python/pyarrow/tests/test_feather.py

@@ -426,7 +426,11 @@ def test_empty_strings(version):
 @pytest.mark.pandas
 def test_all_none(version):
     df = pd.DataFrame({'all_none': [None] * 10})
-    _check_pandas_roundtrip(df, version=version)
+    if version == 1:
+        expected = df.astype("str")
+    else:
+        expected = df
+    _check_pandas_roundtrip(df, version=version, expected=expected)
 
 
 @pytest.mark.pandas