chore: add py39a alpha test

Author: TheKevJames

.circleci/config.yml

@@ -46,11 +46,13 @@ jobs:
       - run: tox -e coveralls<<parameters.cov_version>>
 
 workflows:
-  run-jobs:
+  lint:
     jobs:
       - linter/pre-commit:
           python_version: 3.7.5
 
+  test-cpython:
+    jobs:
       - toxpy:
           name: test-py3.5
           docker_image: '3.5'
@@ -77,9 +79,21 @@ workflows:
             parameters:
               cov_version: ['41', '5']
 
+  test-pypy:
+    jobs:
       - toxpypy:
           name: test-pypy<<matrix.docker_image>>-cov<<matrix.cov_version>>
           matrix:
             parameters:
               cov_version: ['41', '5']
               docker_image: ['3-5', '3-6', '3-7']
+
+  test-alphaversions:
+    jobs:
+      - toxpy:
+          name: test-py3.9-alpha-cov<<matrix.cov_version>>
+          docker_image: '3.9.0a2'
+          tox_environment: py39
+          matrix:
+            parameters:
+              cov_version: ['41', '5']

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py35-cov41-{default,pyyaml},py{36,37,38,py3}-cov{41,5}-{default,pyyaml}
+envlist = py35-cov41-{default,pyyaml},py{36,37,38,39,py3}-cov{41,5}-{default,pyyaml}
 
 [gh-actions]
 python =