typing-extensions 4.0 sdist issue

[dtrodrigues]

import typing_extensions fails from the sdist for 4.0. This works for 3.x

[root@b2fff8624d4d ~]# python3 -m pip install  --no-binary :all: typing-extensions==4.0.0
Collecting typing-extensions==4.0.0
  Using cached typing_extensions-4.0.0.tar.gz (37 kB)
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
  Preparing metadata (pyproject.toml) ... done
Building wheels for collected packages: typing-extensions
  Building wheel for typing-extensions (pyproject.toml) ... done
  Created wheel for typing-extensions: filename=typing_extensions-4.0.0-py3-none-any.whl size=22635 sha256=217b105e4382e579581f72d69a2390a59625aa55787f6f3c83f48e88e935c988
  Stored in directory: /root/.cache/pip/wheels/23/1c/b9/a6843f8ee0b06cae64a7fa6dcc1af022bc4fd3ba707147db2d
Successfully built typing-extensions
Installing collected packages: typing-extensions
Successfully installed typing-extensions-4.0.0
WARNING: Running pip as the 'root' user can result in broken permissions and conflicting behaviour with the system package manager. It is recommended to use a virtual environment instead: https://pip.pypa.io/warnings/venv
[root@b2fff8624d4d ~]# python3 -c 'import typing_extensions'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
ModuleNotFoundError: No module named 'typing_extensions'
[root@b2fff8624d4d ~]# pip uninstall -y typing-extensions
Found existing installation: typing-extensions 4.0.0
Uninstalling typing-extensions-4.0.0:
  Successfully uninstalled typing-extensions-4.0.0
WARNING: Running pip as the 'root' user can result in broken permissions and conflicting behaviour with the system package manager. It is recommended to use a virtual environment instead: https://pip.pypa.io/warnings/venv
[root@b2fff8624d4d ~]# python3 -m pip install --no-binary :all: typing-extensions==3.10.0.2
Collecting typing-extensions==3.10.0.2
  Using cached typing_extensions-3.10.0.2.tar.gz (46 kB)
  Preparing metadata (setup.py) ... done
Skipping wheel build for typing-extensions, due to binaries being disabled for it.
Installing collected packages: typing-extensions
    Running setup.py install for typing-extensions ... done
Successfully installed typing-extensions-3.10.0.2
WARNING: Running pip as the 'root' user can result in broken permissions and conflicting behaviour with the system package manager. It is recommended to use a virtual environment instead: https://pip.pypa.io/warnings/venv
[root@b2fff8624d4d ~]# python3 -c 'import typing_extensions'
[root@b2fff8624d4d ~]# echo $?
0
[root@b2fff8624d4d ~]# uname -a 
Linux b2fff8624d4d 4.4.0-210-generic python/typing#242-Ubuntu SMP Fri Apr 16 09:57:56 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
[root@b2fff8624d4d ~]# cat /etc/redhat-release 
Fedora release 34 (Thirty Four)
[root@b2fff8624d4d ~]# python3 --version
Python 3.9.7
[root@b2fff8624d4d ~]# python3 -m pip --version
pip 21.3.1 from /usr/local/lib/python3.9/site-packages/pip (python 3.9)

[sobolevn]

Related #30

[AA-Turner]

When I proposed the build system changes it seemed like you could trick flit by overriding the module name to include the (non standard) src_py3 directory.

https://github.com/python/typing/blob/28b64f4fea5d9a1c3b3df7dd306892615f0ff728/typing_extensions/pyproject.toml#L65-L67

It seems though that this has stopped working, and I'm not entirely sure why.

A potential work-around would be to update the build instructions in CONTRIBUTING.md to something like:

• pip3 install -U build
• cd typing_extensions
• rm -rf dist/ && cp -r src_py3/ src/
• python -m build .
• rm -rf src/

This builds from a src directory, which flit does support, although is sligtly more work for whoever makes a release.

Another alternative would be to rename src_py3 to src, but that does have some drawbacks (you need to use git log --follow not git log)

A

[AA-Turner]

(the reason typing_extensions isn't being found in the original bug report is I suspect it has been installed as src_py3.typing_extensions -- or at least that was what was happening locally on my testing.

A

[JelleZijlstra]

Thanks for investigating this! Let's just rename src/ so we follow a standard layout.

[JelleZijlstra]

4.0.1 has been released with a working sdist.