Add support for pyproject.toml files when adding --editable projects …

[ughstudios]

There is currently a problem where setup_reader.py can only read setup.cfg or setup.py files for adding local packages. This adds support for flitcore and other backends that are defined in pyproject.toml files

Resolves: #7669

[dimbleby]

immediate thoughts

• general idea seems good, pep-621 compliant pyproject.toml are beginning to appear in the wild and it's good to get a first step in supporting them
• this code certainly doesn't want to be in a class called SetupReader, it's not dealing with setup files, suggest instead introducing something new and refactoring PackageInfo.from_directory()
• I don't think this should be tied to flit: pep 621 is a standard and other backends support it
• I'd anti-recommend using tomlkit to parse pyproject.toml here. poetry already has tomllib in its dependencies - that'll be faster and also sidestep the type-checking issues currently visible in the pipeline
• needs testcases

[ughstudios]

I'd anti-recommend using tomlkit to parse pyproject.toml here. poetry already has tomllib in its dependencies - that'll be faster and also sidestep the type-checking issues currently visible in the pipeline

The codebase I work on is only 3.10, do you mind if I add a fallback to use tomlkit for versions <3.11? tomllib is only available in 3.11.

[dimbleby]

The codebase I work on is only 3.10, do you mind if I add a fallback to use tomlkit for versions <3.11? tomllib is only available in 3.11.

from poetry.utils._compat import tomllib

[ughstudios]

Is there a way to run these tests at my desk so I don't keep spamming you? NVM I guess I can just run each of them manually.

[ughstudios]

I'm running through all of the tests in the test suite. Are any of the tests known to be broken? It seems like my change has broken like 10+ tests :(

[dimbleby]

If you've figured out how to run the tests then you can very easily verify for yourself that they pass without your changes.

On the plus side this probably points you in the right direction for figuring out where to add new tests.

[FFY00]

Looks good. I think the test failures are just due to the test suite relying too much on mocks, making it fragile when we touch the internals. I am also getting them in #7703, but haven't gotten around to look at them.

[FFY00]

IMO, instead of putting this here, we should probably create a from_project_static_files which tries from_pyproject_toml and then from_setup_files, and then replace all existing from_setup_files usages with from_project_static_files.

[ughstudios]

I'll have to do this on Monday when I'm back at my desk. Are you one of the maintainers of poetry? It says "FFY00 approved these changes 3 days ago."