add tox config (#294)

* add basic tox config

* Use tox in GitHub CI

.github/workflows/ci.yml

@@ -1,3 +1,4 @@
+# Uses https://github.com/ymyzk/tox-gh-actions
 name: ci
 
 on: [push, pull_request]
@@ -8,7 +9,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        python-version: ["3.7", "3.8", "3.9", "3.10", '3.11.0-rc - 3.11']
+        python-version: ["3.7", "3.8", "3.9", "3.10", "3.11.0-rc - 3.11"]
 
         os: [ubuntu-latest]
 
@@ -20,15 +21,14 @@ jobs:
       with:
         python-version: ${{ matrix.python-version }}
 
-    - name: Update pip, setuptools + wheel
+    - name: Update pip and setuptools
       run: |
-        python -m pip install --upgrade pip setuptools wheel
+        python -m pip install --upgrade pip setuptools
 
-    - name: Install flake8-bugbear w/dev extra install
+    - name: Install tox and tox-gh-actions
       run: |
-        python -m pip install .[dev]
+        python -m pip install tox tox-gh-actions
 
-    - name: Run Unittests
+    - name: Run tox
       run: |
-        coverage run tests/test_bugbear.py
-        coverage report -m
+        tox

DEVELOPMENT.md

@@ -50,6 +50,17 @@ flake8-bugbear uses coverage to run standard unittest tests.
 /path/to/venv/bin/coverage run tests/test_bugbear.py
 ```
 
+You can also use [tox](https://tox.wiki/en/latest/index.html) to test with multiple different python versions, emulating what the CI does.
+
+```console
+/path/to/venv/bin/tox
+```
+will by default run all tests on python versions 3.7 through 3.11. If you only want to test a specific version you can specify the environment with `-e`
+
+```console
+/path/to/venv/bin/tox -e py38
+```
+
 ## Running linter
 
 We format the code with `black` and `isort`. You can run those using `pre-commit`.

pyproject.toml

@@ -47,6 +47,7 @@ Homepage = "https://github.com/PyCQA/flake8-bugbear"
 
 [project.optional-dependencies]
 dev = [
+    "tox",
     "coverage",
     "hypothesis",
     "hypothesmith>=0.2",

tox.ini

@@ -0,0 +1,22 @@
+# The test environment and commands
+[tox]
+# default environments to run without `-e`
+envlist = py37, py38, py39, py310, py311
+
+[gh-actions]
+python =
+    3.7: py37
+    3.8: py38
+    3.9: py39
+    3.10: py310
+    "3.11.0-rc - 3.11": py311
+
+[testenv:{py37, py38, py39, py310, py311}]
+description = Run coverage
+deps =
+    coverage
+    hypothesis
+    hypothesmith
+commands =
+    coverage run tests/test_bugbear.py {posargs}
+    coverage report -m