Support using tox-venv for testing

The tox-venv plugin for tox leverages the venv module from the
Python 3 standard library instead of relying on the third-party
virtualenv project. Its environments differ in minor ways, however,
so to accommodate that we adjust a couple of our tox testenvs. The
dist testenv no longer assumes the wheel package will be installed,
and expressly includes it as a dep. The docs testenv preinstalls
mudpy into the environment so that we can be sure PBR generates the
AUTHORS and ChangeLog files before Sphinx attempts to include them
in any rendered documents.

diff --git a/tox.ini b/tox.ini
index 83a583c..aefc426 100644 (file)
--- a/tox.ini
+++ b/tox.ini
@@ -1,4 +1,4 @@
-# Copyright (c) 2016-2018 mudpy authors. Permission to use, copy,
+# Copyright (c) 2016-2019 mudpy authors. Permission to use, copy,
 # modify, and distribute this software is granted under terms
 # provided in the LICENSE file distributed with this software.
 
@@ -25,6 +25,7 @@ whitelist_externals = rm
 deps =
     pbr
     twine
+    wheel
 commands =
     rm -fr dist
     python setup.py bdist_wheel sdist
@@ -35,6 +36,7 @@ whitelist_externals = rm
 deps = -r{toxinidir}/doc/requirements.txt
 commands =
     rm -fr doc/build
+    python setup.py sdist
     sphinx-build -W -d doc/build/doctrees -b html doc/source/ doc/build/html
 
 [testenv:flake8]