poetry: Poetry 1.4.0 can't build (editable) dependencies requiring setuptools <64

@md384 you are using a (different) ancient backend

you want something like

[build-system]
requires = ["poetry-core>=1.0.0"]
build-backend = "poetry.core.masonry.api"

@md384 you are using a (different) ancient backend

you want something like

[build-system]
requires = ["poetry-core>=1.0.0"]
build-backend = "poetry.core.masonry.api"

After upgrading to poetry 1.4.2 we had an issue where setuptools was finding multiple top level packages, and changing the build-system to the above fixed our issue. This is a huge relief because it means that we don’t have to change our pyproject.toml files to follow pep 621 just yet.

This is for anyone that uses Homebrew on Mac having this issue. I’ve installed poetry with homebrew and I don’t recommend it because over time running brew upgrades created a version mistmatch between the python formula and the poetry formula and I had python 3.11 with a poetry that used the forumla for python 3.12. TLDR: This is what fixed the issue for me:

1. install the python you want with homebrew. brew install python@3.11
2. use pip that came with that python to install pipx. pip3.11 install pipx
3. use pipx to install poetry pipx install poetry

Now poetry will be tied to that python version you chose and those errors will go away.

pretty much all comments on this are unrelated to the thing that it actually reports, which is a very specific issue about editable dependencies and pins to old versions of setuptools.

setuptools 64.0 was not that old when this was reported: but it is now a year older - the likelihood and value of anyone doing anything with this are both diminishing by the day.

suggest that the issue might as well be be closed out, it seems to be acting only as a honeytrap

so I think pip makes this work by calling setup.py develop - which they will stop doing per https://github.com/pypa/pip/issues/11457 (but perhaps not soon)

poetry is often at the vanguard of dropping support for such things (or less willing to sink effort into backwards compatibility, depending on your point of view). eg see also its insistence on pep-517 builds

hard to say as yet how common it is for projects deliberately to pin to an old version of setuptools. it feels like an unusual thing to do; on the other hand you’ve raised this barely a day after poetry 1.4.0 was released so perhaps there are more like you out there.

you say that you don’t particularly care about support for older setuptools and I tend to think that we should encourage that position. ie I’d advocate for poetry telling people who run into this: you need to allow a newer setuptools (or fall back to the old installer, or just not use poetry).

dunno whether this is worth a new error message specifically calling out this possible cause, perhaps it depends how many duplicates of this issue show up!

Regardless, thanks for the report, it has sent me down an interesting technical rabbit-hole…

related to #7574? not sure I understand how all the parts fit together but I’d try with that fix anyway

This is still happening, although the circumstances for it are admittedly weird.

Yeah, seems poetry init nowadays creates:

[build-system]
requires = ["poetry-core"]
build-backend = "poetry.core.masonry.api"

We ran into the same issue that @JacobHayes mentioned since we updated to Poetry 1.4.0 with an editable dependency:

[tool.poetry.dependencies]
shared = {path = "../shared", develop = true}

Poetry install fails with:

Installing shared (0.0.3 /builds/platform/shared)
  ChefBuildError
  Backend operation failed: HookMissing('build_editable')
  at /usr/local/lib/python3.8/site-packages/poetry/installation/chef.py:152 in _prepare
      148│ 
      149│                 error = ChefBuildError("\n\n".join(message_parts))
      150│ 
      151│             if error is not None:
    → 152│                 raise error from None
      153│ 
      154│             return path
      155│ 
      156│     def _prepare_sdist(self, archive: Path, destination: Path | None = None) -> Path:
Note: This error originates from the build backend, and is likely not a problem with poetry but with shared (0.0.3 /builds/platform/shared) not supporting PEP 517 builds. You can verify this by running 'pip wheel --use-pep517 "shared @ file:///builds/platform/shared ; python_version >= "3.8" and python_version < "4.0""'.

The check for pep517 succeeds:

$ pip wheel --use-pep517 "shared @ file:///builds/platform/shared"
Processing /builds/platform/shared
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
  Preparing metadata (pyproject.toml) ... done
...
...
...
Saved ./setuptools-67.4.0-py3-none-any.whl
Building wheels for collected packages: shared
  Building wheel for shared (pyproject.toml) ... done
  Created wheel for shared: filename=shared-0.0.3-py3-none-any.whl size=57753 sha256=b191d7f34830f93955e6c7cb3e48804755988fb5f92672d5c8188f48867bf98f
  Stored in directory: /tmp/pip-ephem-wheel-cache-1u8wosvq/wheels/22/cc/8a/beebc660a7666f45746f26a1401c4cb6ed777b35c62efb5744
Successfully built shared

For now we went back to Poetry 1.3.2

Edit Forgot to mention: We use setuptools >67 in all projects so here it can not be related to a pinned older version in a sub-dependency.