# swegym / pandas-dev__pandas-50170 - taskset: [swegym](https://harnessreport.com/tasks/swegym.md) - difficulty: hard - category: debugging - language: - runnable from the site: no - agent timeout: 3000s ## Results by harness _none yet_ ## Instruction ``` BUG: `Series` slicing can fail for extension array `Index` ### Pandas version checks - [X] I have checked that this issue has not already been reported. - [X] I have confirmed this bug exists on the [latest version](https://pandas.pydata.org/docs/whatsnew/index.html) of pandas. - [ ] I have confirmed this bug exists on the main branch of pandas. ### Reproducible Example ```python import pandas as pd s = pd.Series(range(5), index=pd.Index(range(5), dtype=int)) print(s.loc[4:5]) # works # Fails with both `numpy`- and `pyarrow`-backed extension arrays for the index s = pd.Series(range(5), index=pd.Index(range(5), dtype="Int64")) print(s.loc[4:5]) # fails s = pd.Series(range(5), index=pd.Index(range(5), dtype="int64[pyarrow]")) print(s.loc[4:5]) # fails ``` ### Issue Description I ran into an issue where slicing a series (via `.loc`) works for when using an index with `dtype=int`, but fails when I cast the index to use either `numpy`- or `pyarrow`-backed extension arrays. ### Expected Behavior I think these are all valid `.loc` calls that should return the corresponding selection ### Installed Versions <details> ``` INSTALLED VERSIONS ------------------ commit : 8dab54d6573f7186ff0c3b6364d5e4dd635ff3e7 python : 3.9.15.final.0 python-bits : 64 OS : Darwin OS-release : 21.6.0 Version : Darwin Kernel Version 21.6.0: Thu Sep 29 20:12:57 PDT 2022; root:xnu-8020.240.7~1/RELEASE_X86_64 machine : x86_64 processor : i386 byteorder : little LC_ALL : None LANG : en_US.UTF-8 LOCALE : en_US.UTF-8 pandas : 1.5.2 numpy : 1.23.5 pytz : 2022.6 dateutil : 2.8.2 setuptools : 59.8.0 pip : 22.3.1 Cython : None pytest : 7.2.0 hypothesis : None sphinx : 4.5.0 blosc : None feather : None xlsxwriter : None lxml.etree : None html5lib : 1.1 pymysql : None psycopg2 : None jinja2 : 3.1.2 IPython : 8.7.0 pandas_datareader: None bs4 : 4.11.1 bottleneck : None brotli : fastparquet : 2022.11.0 fsspec : 2022.11.0 gcsfs : None matplotlib : None numba : None numexpr : 2.8.3 odfpy : None openpyxl : None pandas_gbq : None pyarrow : 10.0.1 pyreadstat : None pyxlsb : None s3fs : 2022.11.0 scipy : 1.9.3 snappy : sqlalchemy : 1.4.44 tables : 3.7.0 tabulate : None xarray : 2022.11.0 xlrd : None xlwt : None zstandard : None tzdata : None ``` </details> ``` --- Harness Report runs agent harnesses from their GitHub repos on Harbor tasks and records every model call. Every page is also `.md` and `.json`; index: https://harnessreport.com/llms.txt · MCP: https://harnessreport.com/mcp