Enforce 'isort' formatter

.github/workflows/tox.yml

@@ -66,6 +66,9 @@ jobs:
       - name: Install Node dependencies
         run: |
           npm install -g markdownlint-cli jshint csslint
+      - name: Check with isort
+        if: always()
+        run: python -m tox -e isort && git diff --exit-code
       - name: Check with black
         if: always()
         run: python -m tox -e black && git diff --exit-code

requirements/test.txt

@@ -1,3 +1,4 @@
 coverage
 black
+isort
 flake8

setup.cfg

@@ -5,6 +5,10 @@ license_file = LICENSE
 max-line-length = 119
 extend-ignore = E203
 
+[isort]
+profile = black
+line_length = 100
+
 [compile_catalog]
 statistics = True
 domain = messages

tox.ini

@@ -20,6 +20,10 @@ commands=
 deps=-rrequirements/test.txt
 commands={envbindir}/black -l100 -tpy36 --skip-string-normalization mkdocs
 
+[testenv:isort]
+deps=-rrequirements/test.txt
+commands={envbindir}/isort mkdocs
+
 [testenv:flake8]
 deps=-rrequirements/test.txt
 commands={envbindir}/flake8 mkdocs