Make development dependencies available as extras (#194)

Fixes #190

CONTRIBUTING.md

@@ -12,8 +12,7 @@ To contribute to Sygnal, ensure you have Python 3.7 or newer and then run:
 
 ```
 python3 -m venv venv
-./venv/bin/pip install -e .
-./venv/bin/pip install -U black flake8 isort mypy mypy-zope tox
+./venv/bin/pip install -e '.[dev]'
 ```
 
 This creates an isolated virtual Python environment ("virtualenv") just for

changelog.d/194.misc

@@ -0,0 +1 @@
+Development dependencies are now avaible as extras. Contributed by Hillery Shay.

setup.py

@@ -52,5 +52,15 @@ def read(fname):
         "pywebpush>=1.13.0",
         "py-vapid>=1.7.0",
     ],
+    extras_require={
+        "dev": [
+            "black==19.10b0",
+            "flake8==3.8.3",
+            "isort~=5.0",
+            "mypy==0.780",
+            "mypy-zope==0.2.7",
+            "tox",
+        ]
+    },
     long_description=read("README.rst"),
 )

tox.ini

@@ -15,20 +15,15 @@ usedevelop=true
 commands = trial tests
 
 [testenv:check_codestyle]
-skip_install = True
-deps =
-  # pin deps so we don't start failing when they are updated
-  flake8==3.8.3
-  black==19.10b0
-  isort~=5.0
+extras =
+  dev
 commands =
   flake8 .
   black --check --diff .
   isort --check-only --diff .
 
 [testenv:check_types]
-deps =
-  mypy==0.780
-  mypy-zope==0.2.7
+extras = 
+  dev
 commands =
   mypy .