BUG: TypeError when shifting DataFrame created by concatenation of slices and fills with values

[wjsi]

• I have checked that this issue has not already been reported.

• I have confirmed this bug exists on the latest version of pandas.

• (optional) I have confirmed this bug exists on the master branch of pandas.

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Note: Please read this guide detailing how to provide the necessary information for us to reproduce your bug.

Code Sample, a copy-pastable example

import numpy as np
import pandas as pd
npa = np.random.RandomState(0).randint(1000, size=(20, 8))
df = pd.DataFrame(npa, columns=[f'c{i}' for i in range(8)])
pd.concat([df.iloc[:6, 3:5], df.iloc[:6, 6:8]], axis=1).shift(periods=2, axis=1, freq=None, fill_value=0)

Traceback (most recent call last):
  File "/Users/wenjun/miniconda3/lib/python3.8/site-packages/IPython/core/interactiveshell.py", line 3417, in run_code
    exec(code_obj, self.user_global_ns, self.user_ns)
  File "<ipython-input-4-9916dba4e800>", line 1, in <module>
    pd.concat([df.iloc[:6, 3:5], df.iloc[:6, 6:8]], axis=1).shift(periods=2, axis=1, freq=None, fill_value=0)
  File "/Users/wenjun/miniconda3/lib/python3.8/site-packages/pandas/core/frame.py", line 5313, in shift
    return super().shift(
  File "/Users/wenjun/miniconda3/lib/python3.8/site-packages/pandas/core/generic.py", line 9179, in shift
    new_data = self._mgr.shift(
  File "/Users/wenjun/miniconda3/lib/python3.8/site-packages/pandas/core/internals/managers.py", line 393, in shift
    result = self.reindex_indexer(
  File "/Users/wenjun/miniconda3/lib/python3.8/site-packages/pandas/core/internals/managers.py", line 669, in reindex_indexer
    new_blocks = self._slice_take_blocks_ax0(
  File "/Users/wenjun/miniconda3/lib/python3.8/site-packages/pandas/core/internals/managers.py", line 714, in _slice_take_blocks_ax0
    sl_type, slobj, sllen = _preprocess_slice_or_indexer(
  File "/Users/wenjun/miniconda3/lib/python3.8/site-packages/pandas/core/internals/managers.py", line 2033, in _preprocess_slice_or_indexer
    raise TypeError(type(slice_or_indexer), dtype)
TypeError: (<class 'list'>, None)

Problem description

shift should work without exception. When df._data._consolidate_inplace() is called before shift, it works well. Thus consolidation might be missing, just like #35488.

Expected Output

   c3  c4   c6   c7
0   0   0  192  835
1   0   0  754  804
2   0   0  705  486
3   0   0  537  845
4   0   0  709  847
5   0   0  755  797

Output of pd.show_versions()

INSTALLED VERSIONS

commit : f00ed8f
python : 3.8.5.final.0
python-bits : 64
OS : Darwin
OS-release : 19.6.0
Version : Darwin Kernel Version 19.6.0: Thu May 6 00:48:39 PDT 2021; root:xnu-6153.141.33~1/RELEASE_X86_64
machine : x86_64
processor : i386
byteorder : little
LC_ALL : None
LANG : None
LOCALE : zh_CN.UTF-8
pandas : 1.3.0
numpy : 1.18.5
pytz : 2021.1
dateutil : 2.8.1
pip : 20.2.2
setuptools : 49.6.0.post20200814
Cython : 0.29.23
pytest : 6.2.2
hypothesis : 6.3.0
sphinx : 3.2.1
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : 2.11.2
IPython : 7.17.0
pandas_datareader: None
bs4 : None
bottleneck : None
fsspec : None
fastparquet : 0.4.2
gcsfs : None
matplotlib : 3.2.2
numexpr : 2.7.1
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : 4.0.0
pyxlsb : None
s3fs : None
scipy : 1.6.0
sqlalchemy : 1.3.18
tables : None
tabulate : None
xarray : None
xlrd : None
xlwt : None
numba : 0.53.0

[wjsi]

When fill_value is not specified, things work well, but when fill_value is filled, even if the value is None, the error emerges. Same thing happen when testing with latest master branch.

[wjsi]

Any one please take a look at this issue? Problem still exists in current master branch (9c0a1ebec6028d98e47c5664fd2cad173bfd9c21). I reopened the PR as int-fill for axis=1 is not implemented and is expected to fail.

[wjsi]

New issue #42719 opened