Merge "Check that all po/pot files are valid"

tox.ini

@@ -12,13 +12,18 @@ deps = -r{toxinidir}/requirements.txt
        setuptools_git>=0.4
 commands = {envpython} run_tests.py
 	    python setup.py testr --slowest
+whitelist_externals = bash
 
 [tox:jenkins]
 sitepackages = True
 downloadcache = ~/cache/pip
 
 [testenv:pep8]
-commands = flake8
+commands =
+    flake8
+    # Check that .po and .pot files are valid:
+    bash -c "find trove -type f -regex '.*\.pot?' -print0 | \
+             xargs -0 -n 1 msgfmt --check-format -o /dev/null"
 
 [testenv:cover]
 basepython = python2.7