misc: add black/isort/pyupgrade files & notes (#54260)

.git-blame-ignore-revs

@@ -0,0 +1,2 @@
+# misc: apply black/isort/pyupgrade (#54260)
+72332027586fb99a6dfbc0130cd34987096bd586

.pre-commit-config.yaml

@@ -0,0 +1,18 @@
+# See https://pre-commit.com for more information
+# See https://pre-commit.com/hooks.html for more hooks
+repos:
+-   repo: https://github.com/psf/black
+    rev: 20.8b1
+    hooks:
+    - id: black
+      args: ['--target-version', 'py37', '--skip-string-normalization', '--line-length', '110']
+-   repo: https://github.com/PyCQA/isort
+    rev: 5.7.0
+    hooks:
+    - id: isort
+      args: ['--profile', 'black', '--line-length', '110']
+-   repo: https://github.com/asottile/pyupgrade
+    rev: v2.20.0
+    hooks:
+    - id: pyupgrade
+      args: ['--keep-percent-format', '--py37-plus']

README.rst

@@ -11,6 +11,27 @@ To use just do::
       django_journal.record('my-tag', '{user} did this to {that}',
                  user=request.user, that=model_instance)
 
+Code Style
+==========
+
+black is used to format the code, using these parameters::
+
+    black --target-version py37 --skip-string-normalization --line-length 110
+
+There is .pre-commit-config.yaml to use pre-commit to automatically run black
+before commits. (execute `pre-commit install` to install the git hook.)
+
+isort is used to format the imports, using these parameter::
+
+    isort --profile black --line-length 110
+
+pyupgrade is used to automatically upgrade syntax, using these parameters::
+
+    pyupgrade --keep-percent-format --py37-plus
+
+There is .pre-commit-config.yaml to use pre-commit to automatically run black,
+isort and pyupgrade before commits. (execute `pre-commit install` to install
+the git hook.)
 
 Admin display
 -------------

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 toxworkdir = /tmp/tox-{env:USER}/django-journal/{env:BRANCH_NAME:}
-envlist = py3-coverage-django111,py3-django22
+envlist = py3-coverage-django111,py3-django22,code-style
 
 
 [testenv]
@@ -17,3 +17,10 @@ setenv =
   coverage: COVERAGE=--cov-append --cov-report xml --cov-report html --cov=django_journal/
 commands =
   py.test {posargs: {env:COVERAGE:} --junitxml=junit-{envname}.xml tests/}
+
+[testenv:code-style]
+skip_install = true
+deps =
+  pre-commit
+commands =
+  pre-commit run --all-files --show-diff-on-failure