PEP 660 and setuptools

Packaging
6

@blink1073 just FYI, I am currently working in this PoC for the proposal above: GitHub - abravalheri/setuptools at editable-link-tree (WIP):

  • For the “lax/loose” approach, either a static .pth file is produced or a MetaPathFinder is added, depending on the project layout.
  • For the “strict” mode, the existing files detected by package_data get linked (symlink if possible, hardlink otherwise).

In both scenarios, the <package>-<version>.data wheel entry is generated normally as it would in a conventional wheel.

I may be wrong here, but after reading the specs for editable installs and the wheel format I was under the impression that there is not much of a choice for the .data directory other than having it baked statically inside the .whl archive.

For Python modules and package_data we can use the trick suggested in PEP 660 of creating a link tree out-off-band and then add adding a static .pth file pointing to it, but I don’t know if adding the *.data directory there would have the intended effects. For example, would sysconfig.get_path work to detect these files?

Currently we don’t have a mechanism to represent links in the wheel, and I have the impression that any of the other well-known approaches, such as a MetaPathFinder or a static .pth file, would be of no use for the *.data directory…