Run on 3.7 proper

.travis.yml

@@ -24,6 +24,10 @@ matrix:
       env: TOXENV=pypy
     - python: "pypy3"
       env: TOXENV=pypy3
+    - python: "3.7"
+      env: TOXENV=py37
+      dist: xenial
+      sudo: true
 
     # Prevent breakage by a new releases
     - python: "3.6-dev"

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = pre-commit,lint,py27,py34,py35,py36,pypy,pypy3,manifest,docs,readme,changelog,coverage-report
+envlist = pre-commit,lint,py27,py34,py35,py36,py37,pypy,pypy3,manifest,docs,readme,changelog,coverage-report
 
 
 [testenv]
@@ -16,7 +16,7 @@ extras = tests
 commands = coverage run --parallel -m pytest {posargs}
 
 
-[testenv:py36]
+[testenv:py37]
 # Python 3.6+ has a number of compile-time warnings on invalid string escapes.
 # PYTHONWARNINGS=d and --no-compile below make them visible during the Tox run.
 install_command = pip install --no-compile {opts} {packages}