use black to enforce codestyle

[ziirish]

Any thoughts on using black in order to enforce a coding style?

This way we don't have to bother our contributors with a codestyle, they just have to run black prior submitting a PR.

[SVilgelm]

I like it, I already have the GitHub Actions to enforce black code style: https://github.com/sv-tools/marshmallow-objects/blob/master/.github/workflows/test.yml#L35

[SVilgelm]

It's going to be a huge diff git diff --stat:

 doc/conf.py                             |  258 ++++++++--------
 examples/todo.py                        |   72 ++---
 examples/todo_blueprint.py              |   74 ++---
 examples/todo_simple.py                 |    9 +-
 examples/todomvc.py                     |   65 +++--
 examples/xml_representation.py          |   20 +-
 examples/zoo/__init__.py                |    6 +-
 examples/zoo/cat.py                     |   33 ++-
 examples/zoo/dog.py                     |   33 ++-
 flask_restx/__about__.py                |    6 +-
 flask_restx/__init__.py                 |   44 +--
 flask_restx/_http.py                    |  245 +++++++++-------
 flask_restx/api.py                      |  420 +++++++++++++++-----------
 flask_restx/apidoc.py                   |   22 +-
 flask_restx/cors.py                     |   40 ++-
 flask_restx/errors.py                   |   23 +-
 flask_restx/fields.py                   |  399 +++++++++++++++----------
 flask_restx/inputs.py                   |  266 +++++++++--------
 flask_restx/marshalling.py              |   44 ++-
 flask_restx/mask.py                     |   82 +++---
 flask_restx/model.py                    |  122 ++++----
 flask_restx/namespace.py                |  182 +++++++-----
 flask_restx/postman.py                  |  169 ++++++-----
 flask_restx/representations.py          |    6 +-
 flask_restx/reqparse.py                 |  221 ++++++++------
 flask_restx/resource.py                 |   24 +-
 flask_restx/schemas/__init__.py         |   45 +--
 flask_restx/swagger.py                  |  499 ++++++++++++++++---------------
 flask_restx/utils.py                    |   43 +--
 setup.py                                |  105 +++----
 tasks.py                                |  185 ++++++------
 tests/benchmarks/bench_marshalling.py   |   28 +-
 tests/benchmarks/bench_swagger.py       |   58 ++--
 tests/conftest.py                       |   40 +--
 tests/legacy/test_api_legacy.py         |  201 +++++++------
 tests/legacy/test_api_with_blueprint.py |  127 ++++----
 tests/test_accept.py                    |  102 ++++---
 tests/test_api.py                       |  227 ++++++++-------
 tests/test_apidoc.py                    |  120 ++++----
 tests/test_cors.py                      |   39 +--
 tests/test_errors.py                    |  373 ++++++++++++------------
 tests/test_fields.py                    | 1162 ++++++++++++++++++++++++++++++++++++------------------------------------
 tests/test_fields_mask.py               | 1058 ++++++++++++++++++++++++++++--------------------------------------
 tests/test_inputs.py                    | 1251 +++++++++++++++++++++++++++++++++++++++++++-----------------------------------
 tests/test_logging.py                   |   32 +-
 tests/test_marshalling.py               |  571 +++++++++++++++++++-----------------
 tests/test_model.py                     |  757 ++++++++++++++++++-----------------------------
 tests/test_namespace.py                 |  142 ++++-----
 tests/test_payload.py                   |  285 +++++++++---------
 tests/test_postman.py                   |  313 ++++++++++----------
 tests/test_reqparse.py                  |  915 +++++++++++++++++++++++++++++----------------------------
 tests/test_schemas.py                   |   32 +-
 tests/test_swagger.py                   | 3590 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--------------------------------------------------------------------------------------------------------------------
 tests/test_swagger_utils.py             |  173 +++++------
 tests/test_utils.py                     |  114 +++-----
 55 files changed, 7798 insertions(+), 7674 deletions(-)

[callamd]

Black is an excellent tool. I think the pro's are:

• Reduces bikeshedding (this is the biggest +)
• Improves readability and standardisation

It's a big diff which is a shame but if we're going to do it early in the project would be the best time, right?

I think it's better to add the check as a pre-commit hook. This prevents logs like

• 15:00 fixed x, y ,z bug
• 15:05 black formatting

[SVilgelm]

if we want to have a black, we need to decide what line length we need?

• pep8 default is 79
• black's default is 87
• also some projects are using 120

I would recommend 120, I'm using it on several projects and it works great.

[ziirish]

I'm personally OK with black's default.

The purpose of using black is that we don't have to care with all the details. You write the code the way you like and then you invoke black prior committing your changes.

[SVilgelm]

@ziirish I've created the PR: #60

[SVilgelm]

we also need to adjust linter

[SVilgelm]

so the problems I found with black.

1. It requires python >= 3.6 to run.
2. it cannot be installed in pypy3 env, due to typed-ast module isn't compatible with pypy3: Support PyPy (easy) psf/black#727

So to fix all of those problems, I introduced new (first) step in the workflow: checks
It uses only py3.8 to run the checks, like black formatting or any other, what doesn't need to be run on different python versions.

[SVilgelm]

Also, I moved some requirements from develop.pip to test.pip

[SVilgelm]

One more, now we have the flake8 configured for 120. We can add pyproject.toml with:

[tool.black]
line-length = 120

and it will work as expected, the black . command will reformat everything with 120

[SVilgelm]

It will reduce the number of lines for ~1500:
55 files changed, 6269 insertions(+), 7744 deletions(-)

[SVilgelm]

One more, the black is just a formatter, and the ast is same after the black was run, I think we still need to use a linter, maybe pylint, because it validates a bit more, than the correct code style.

[SVilgelm]

So, Let's vote ;-)

❤️ for 120 (the current style)
👍 for 88 (the black's default)
👎 for 79 (the pep8's default)

😈