PEP-517 support

[orsinium]

Changelog-friendly one-liner: Support for pyproject.toml as input dependency file (PEP-517).

If pyproject.toml is explicitly specified as input file, pip-compile will use it. Example:

pip-compile --output-file requirements.txt pyproject.toml

Included a simple test for flit

Closes #1047

Contributor checklist

• Provided the tests for the changes.
• Gave a clear one-line description in the PR (that the maintainers can add to CHANGELOG.md on release).
• Assign the PR to an existing or new milestone for the target version (following Semantic Versioning).

[codecov]

Codecov Report

Merging #1356 (6207ed9) into master (37946f2) will increase coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head 6207ed9 differs from pull request most recent head e0a3b3d. Consider uploading reports for the commit e0a3b3d to get more accurate results

@@           Coverage Diff           @@
##           master    #1356   +/-   ##
=======================================
  Coverage   99.65%   99.65%           
=======================================
  Files          33       33           
  Lines        2915     2940   +25     
  Branches      308      308           
=======================================
+ Hits         2905     2930   +25     
  Misses          5        5           
  Partials        5        5           

Impacted Files	Coverage Δ
piptools/scripts/compile.py	100.00% <100.00%> (ø)
tests/test_cli_compile.py	100.00% <100.00%> (ø)

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[atugushev]

Thanks for addressing the suggestion and adding a test 🙏🏻 A few comments below.

[atugushev]

Nice! One last thing. Could dedent be used alongside triple-quote strings? That helps to reduce extra indentations.

[atugushev]

Could we use pytest.param(..., id='..') instead of comments? That improves pytest -v output.

Before:

tests/test_cli_compile.py::test_input_formats[setup.cfg-\n                [metadata]\n                name = sample_lib\n                author = Vincent Driessen\n                author_email = me@nvie.com\n\n                [options]\n                packages = find:\n                install_requires =\n                    small-fake-a==0.1\n                    small-fake-b==0.2\n\n                [options.extras_require]\n                dev =\n                    small-fake-c==0.3\n                    small-fake-d==0.4\n                test =\n                    small-fake-e==0.5\n                    small-fake-f==0.6\n            ] PASSED [ 25%]
tests/test_cli_compile.py::test_input_formats[setup.py-\n                from setuptools import setup\n\n                setup(\n                    name="sample_lib",\n                    version=0.1,\n                    install_requires=["small-fake-a==0.1", "small-fake-b==0.2"],\n                    extras_require={\n                        "dev": ["small-fake-c==0.3", "small-fake-d==0.4"],\n                        "test": ["small-fake-e==0.5", "small-fake-f==0.6"],\n                    },\n                )\n            ] PASSED [ 50%]
tests/test_cli_compile.py::test_input_formats[pyproject.toml-\n                [build-system]\n                requires = ["flit_core >=2,<4"]\n                build-backend = "flit_core.buildapi"\n\n                [tool.flit.metadata]\n                module = "sample_lib"\n                author = "Vincent Driessen"\n                author-email = "me@nvie.com"\n\n                requires = ["small-fake-a==0.1", "small-fake-b==0.2"]\n\n                [tool.flit.metadata.requires-extra]\n                dev  = ["small-fake-c==0.3", "small-fake-d==0.4"]\n                test = ["small-fake-e==0.5", "small-fake-f==0.6"]\n            ] PASSED [ 75%]
tests/test_cli_compile.py::test_input_formats[pyproject.toml-\n                [build-system]\n                requires = ["poetry_core>=1.0.0"]\n                build-backend = "poetry.core.masonry.api"\n\n                [tool.poetry]\n                name = "sample_lib"\n                version = "0.1.0"\n                description = ""\n                authors = ["Vincent Driessen <me@nvie.com>"]\n\n                [tool.poetry.dependencies]\n                python = "*"\n                small-fake-a = "0.1"\n                small-fake-b = "0.2"\n\n                small-fake-c = "0.3"\n                small-fake-d = "0.4"\n                small-fake-e = "0.5"\n                small-fake-f = "0.6"\n\n                [tool.poetry.extras]\n                dev  = ["small-fake-c", "small-fake-d"]\n                test = ["small-fake-e", "small-fake-f"]\n            ] PASSED [100%]

After:

tests/test_cli_compile.py::test_input_formats[setup.cfg] PASSED                                                                                                                                      [ 25%]
tests/test_cli_compile.py::test_input_formats[setup.py] PASSED
tests/test_cli_compile.py::test_input_formats[flit] PASSED
tests/test_cli_compile.py::test_input_formats[poetry] PASSED

[orsinium]

Yep, great idea. Fixed 👍🏿

[webknjaz]

FYI another nice way to do this would be to add ids=('setup.cfg', 'setup.py'). Sometimes it's easier than embedding the ids into each param. But of course, it depends on the situation.

[orsinium]

Good to know, thank you 👍🏿 I think in this situation it looks nice to have it per case.

[webknjaz]

tmpdir is sorta deprecated (well, at least there's a mention of it being replaced). It's always better to use tmp_path which does the same except it injects pathlib.Path objects instead of py.path which are nicer to work with.

[orsinium]

Yep, I know. But all other tests in this file use tmpdir. I think it's better to keep it consistent and migrate all at once.

[atugushev]

LGTM 👍🏻

[atugushev]

@orsinium thanks for the contribution! Awesome job! 🎉