pip show package_name --files lists files incorrectly

[mallamanis]

Description

When running pip show package_name --files the file paths returned are invalid paths. Specifically the prefix is the relative path between the site-packages and the current working directory.

For example:

$ pip show requests --files
Name: requests
Version: 2.26.0
Summary: Python HTTP for Humans.
Home-page: https://requests.readthedocs.io
Author: Kenneth Reitz
Author-email: me@kennethreitz.org
License: Apache 2.0
Location: /home/miallama/pip-bug-replication/lib/python3.8/site-packages
Requires: idna, urllib3, charset-normalizer, certifi
Required-by:
Files:
  ../../../../requests-2.26.0.dist-info/INSTALLER
  ../../../../requests-2.26.0.dist-info/LICENSE
  ../../../../requests-2.26.0.dist-info/METADATA
  ../../../../requests-2.26.0.dist-info/RECORD
  ../../../../requests-2.26.0.dist-info/WHEEL
  ../../../../requests-2.26.0.dist-info/top_level.txt
  ../../../../requests/__init__.py
  ../../../../requests/__pycache__/__init__.cpython-38.pyc
  ../../../../requests/__pycache__/__version__.cpython-38.pyc
  ../../../../requests/__pycache__/_internal_utils.cpython-38.pyc
  ../../../../requests/__pycache__/adapters.cpython-38.pyc
  ../../../../requests/__pycache__/api.cpython-38.pyc
  ../../../../requests/__pycache__/auth.cpython-38.pyc
  ../../../../requests/__pycache__/certs.cpython-38.pyc
  ../../../../requests/__pycache__/compat.cpython-38.pyc
  ../../../../requests/__pycache__/cookies.cpython-38.pyc
  ../../../../requests/__pycache__/exceptions.cpython-38.pyc
  ../../../../requests/__pycache__/help.cpython-38.pyc
  ../../../../requests/__pycache__/hooks.cpython-38.pyc
  ../../../../requests/__pycache__/models.cpython-38.pyc
  ../../../../requests/__pycache__/packages.cpython-38.pyc
  ../../../../requests/__pycache__/sessions.cpython-38.pyc
  ../../../../requests/__pycache__/status_codes.cpython-38.pyc
  ../../../../requests/__pycache__/structures.cpython-38.pyc
  ../../../../requests/__pycache__/utils.cpython-38.pyc
...

Note that ../../../../ is the relative path between site-packages and the current working directory in my run.

I suspect that this line introduced in this commit may be responsible.

Expected behavior

Previously, (e.g. with pip==9.0.1 and pip==21.1) the listed files were relative to the site-packages location.

$ pip show requests --files
Name: requests
Version: 2.26.0
Summary: Python HTTP for Humans.
Home-page: https://requests.readthedocs.io
Author: Kenneth Reitz
Author-email: me@kennethreitz.org
License: Apache 2.0
Location: /home/miallama/pip-bug-replication/lib/python3.8/site-packages
Requires: idna, certifi, urllib3, charset-normalizer
Files:
  requests-2.26.0.dist-info/INSTALLER
  requests-2.26.0.dist-info/LICENSE
  requests-2.26.0.dist-info/METADATA
  requests-2.26.0.dist-info/RECORD
  requests-2.26.0.dist-info/WHEEL
  requests-2.26.0.dist-info/top_level.txt
  requests/__init__.py
  requests/__pycache__/__init__.cpython-38.pyc
  requests/__pycache__/__version__.cpython-38.pyc
  requests/__pycache__/_internal_utils.cpython-38.pyc
  requests/__pycache__/adapters.cpython-38.pyc
  requests/__pycache__/api.cpython-38.pyc
  requests/__pycache__/auth.cpython-38.pyc
  requests/__pycache__/certs.cpython-38.pyc
  requests/__pycache__/compat.cpython-38.pyc
  requests/__pycache__/cookies.cpython-38.pyc
  requests/__pycache__/exceptions.cpython-38.pyc
  requests/__pycache__/help.cpython-38.pyc
  requests/__pycache__/hooks.cpython-38.pyc
  requests/__pycache__/models.cpython-38.pyc
  requests/__pycache__/packages.cpython-38.pyc
  requests/__pycache__/sessions.cpython-38.pyc
  requests/__pycache__/status_codes.cpython-38.pyc
  requests/__pycache__/structures.cpython-38.pyc
  requests/__pycache__/utils.cpython-38.pyc
  requests/__version__.py
  requests/_internal_utils.py
  requests/adapters.py
  requests/api.py
  requests/auth.py
  requests/certs.py
  requests/compat.py
...

pip version

21.2.1

Python version

3.8

OS

Ubuntu 18.04

How to Reproduce

1. Install the latest pip
2. Then run pip show some_package --files
3. The paths of the listed files are incorrect.

Output

No response

Code of Conduct

• I agree to follow the PSF Code of Conduct.

[uranusjr]

Thanks for the report! I messed up path manipulation in the new logic, and there's apparently no test cases to catch this.

[uranusjr]

Fix submitted in #10206.