BUG: argument 'axis=1' is silently ignored in DataFrame diff() method when dtype is nullable integer (Int64)

[geppi]

import numpy as np
import pandas as pd
pd.show_versions()

INSTALLED VERSIONS
------------------
commit           : None
python           : 3.7.4.final.0
python-bits      : 64
OS               : Windows
OS-release       : 10
machine          : AMD64
processor        : Intel64 Family 6 Model 78 Stepping 3, GenuineIntel
byteorder        : little
LC_ALL           : None
LANG             : None
LOCALE           : None.None

pandas           : 1.0.3
numpy            : 1.18.1
pytz             : 2019.3
dateutil         : 2.8.1
pip              : 20.0.2
setuptools       : 40.8.0
Cython           : None
pytest           : None
hypothesis       : None
sphinx           : None
blosc            : None
feather          : None
xlsxwriter       : 1.2.8
lxml.etree       : 4.5.0
html5lib         : None
pymysql          : None
psycopg2         : None
jinja2           : 2.10.3
IPython          : 7.11.1
pandas_datareader: None
bs4              : None
bottleneck       : None
fastparquet      : None
gcsfs            : None
lxml.etree       : 4.5.0
matplotlib       : 3.1.3
numexpr          : None
odfpy            : None
openpyxl         : 3.0.3
pandas_gbq       : None
pyarrow          : None
pytables         : None
pytest           : None
pyxlsb           : None
s3fs             : None
scipy            : None
sqlalchemy       : None
tables           : None
tabulate         : None
xarray           : None
xlrd             : None
xlwt             : None
xlsxwriter       : 1.2.8
numba            : None

df = pd.DataFrame([[1,2], [3,np.nan]], index= ['a', 'b'], columns=['A', 'B']).convert_dtypes()
df

	A	B
a	1	2
b	3	<NA>

df.dtypes

A    Int64
B    Int64
dtype: object

df.diff(axis=0)

	A	B
a	<NA>	<NA>
b	2	<NA>

df.diff(axis=1)

	A	B
a	<NA>	<NA>
b	2	<NA>

Conversion to float fixes the issue

df = df.astype(float)
df

	A	B
a	1.0	2.0
b	3.0	NaN

df.diff(axis=1)

	A	B
a	NaN	1.0
b	NaN	NaN

[dsaxton]

I think this is fixed on master, apparently by #32995

[ins] In [2]: df = pd.DataFrame([[1,2], [3,np.nan]], index= ['a', 'b'], columns=['A', 'B']).convert_dtypes()                                                                                                 

[ins] In [3]: df                                                                                                                                                                                             
Out[3]: 
   A     B
a  1     2
b  3  <NA>

[ins] In [4]: df.diff(axis=0)                                                                                                                                                                                
Out[4]: 
      A     B
a  <NA>  <NA>
b     2  <NA>

[ins] In [5]: df.diff(axis=1)                                                                                                                                                                                
Out[5]: 
      A     B
a  <NA>     1
b  <NA>  <NA>

[ins] In [6]: pd.__version__                                                                                                                                                                                 
Out[6]: '1.1.0.dev0+1336.g652a39f50'

cc @jbrockmendel

[geppi]

Thanks.

Then I can close this one.