X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/7190d4f6c0dfcc7fce9adfffc1afc7254a01eae6..882d8795c6ff65c02f2657e596391748d1b6b7f5:/docs/contributing/the_basics.md?ds=inline diff --git a/docs/contributing/the_basics.md b/docs/contributing/the_basics.md index d61f3ec..bc1680e 100644 --- a/docs/contributing/the_basics.md +++ b/docs/contributing/the_basics.md @@ -4,26 +4,20 @@ An overview on contributing to the _Black_ project. ## Technicalities -Development on the latest version of Python is preferred. As of this writing it's 3.9. -You can use any operating system. +Development on the latest version of Python is preferred. You can use any operating +system. -Install all development dependencies using: +Install development dependencies inside a virtual environment of your choice, for +example: ```console -$ pipenv install --dev -$ pipenv shell -$ pre-commit install -``` - -If you haven't used `pipenv` before but are comfortable with virtualenvs, just run -`pip install pipenv` in the virtualenv you're already using and invoke the command above -from the cloned _Black_ repo. It will do the correct thing. - -Non pipenv install works too: +$ python3 -m venv .venv +$ source .venv/bin/activate # activation for linux and mac +$ .venv\Scripts\activate # activation for windows -```console -$ pip install -r test_requirements.txt -$ pip install -e .[d] +(.venv)$ pip install -r test_requirements.txt +(.venv)$ pip install -e .[d] +(.venv)$ pre-commit install ``` Before submitting pull requests, run lints and tests with the following commands from @@ -31,18 +25,75 @@ the root of the black repo: ```console # Linting -$ pre-commit run -a +(.venv)$ pre-commit run -a # Unit tests -$ tox -e py +(.venv)$ tox -e py # Optional Fuzz testing -$ tox -e fuzz +(.venv)$ tox -e fuzz + +# Format Black itself +(.venv)$ tox -e run_self +``` + +### Development + +Further examples of invoking the tests + +```console +# Run all of the above mentioned, in parallel +(.venv)$ tox --parallel=auto + +# Run tests on a specific python version +(.venv)$ tox -e py39 + +# pass arguments to pytest +(.venv)$ tox -e py -- --no-cov -# Optional CI run to test your changes on many popular python projects -$ black-primer [-k -w /tmp/black_test_repos] +# print full tree diff, see documentation below +(.venv)$ tox -e py -- --print-full-tree + +# disable diff printing, see documentation below +(.venv)$ tox -e py -- --print-tree-diff=False ``` +### Testing + +All aspects of the _Black_ style should be tested. Normally, tests should be created as +files in the `tests/data/cases` directory. These files consist of up to three parts: + +- A line that starts with `# flags: ` followed by a set of command-line options. For + example, if the line is `# flags: --preview --skip-magic-trailing-comma`, the test + case will be run with preview mode on and the magic trailing comma off. The options + accepted are mostly a subset of those of _Black_ itself, except for the + `--minimum-version=` flag, which should be used when testing a grammar feature that + works only in newer versions of Python. This flag ensures that we don't try to + validate the AST on older versions and tests that we autodetect the Python version + correctly when the feature is used. For the exact flags accepted, see the function + `get_flags_parser` in `tests/util.py`. If this line is omitted, the default options + are used. +- A block of Python code used as input for the formatter. +- The line `# output`, followed by the output of _Black_ when run on the previous block. + If this is omitted, the test asserts that _Black_ will leave the input code unchanged. + +_Black_ has two pytest command-line options affecting test files in `tests/data/` that +are split into an input part, and an output part, separated by a line with`# output`. +These can be passed to `pytest` through `tox`, or directly into pytest if not using +`tox`. + +#### `--print-full-tree` + +Upon a failing test, print the full concrete syntax tree (CST) as it is after processing +the input ("actual"), and the tree that's yielded after parsing the output ("expected"). +Note that a test can fail with different output with the same CST. This used to be the +default, but now defaults to `False`. + +#### `--print-tree-diff` + +Upon a failing test, print the diff of the trees as described above. This is the +default. To turn it off pass `--print-tree-diff=False`. + ### News / Changelog Requirement `Black` has CI that will check for an entry corresponding to your PR in `CHANGES.md`. If @@ -63,30 +114,20 @@ go back and workout what to add to the `CHANGES.md` for each release. If a change would affect the advertised code style, please modify the documentation (The _Black_ code style) to reflect that change. Patches that fix unintended bugs in -formatting don't need to be mentioned separately though. +formatting don't need to be mentioned separately though. If the change is implemented +with the `--preview` flag, please include the change in the future style document +instead and write the changelog entry under a dedicated "Preview changes" heading. ### Docs Testing If you make changes to docs, you can test they still build locally too. ```console -$ pip install -r docs/requirements.txt -$ pip install [-e] .[d] -$ sphinx-build -a -b html -W docs/ docs/_build/ +(.venv)$ pip install -r docs/requirements.txt +(.venv)$ pip install -e .[d] +(.venv)$ sphinx-build -a -b html -W docs/ docs/_build/ ``` -## black-primer - -`black-primer` is used by CI to pull down well-known _Black_ formatted projects and see -if we get source code changes. It will error on formatting changes or errors. Please run -before pushing your PR to see if you get the actions you would expect from _Black_ with -your PR. You may need to change -[primer.json](https://github.com/psf/black/blob/main/src/black_primer/primer.json) -configuration for it to pass. - -For more `black-primer` information visit the -[documentation](./gauging_changes.md#black-primer). - ## Hygiene If you're fixing a bug, add a test. Run it first to confirm it fails, then fix the bug,