Add tox support, clean up quality violations (#45)

.gitignore

@@ -4,3 +4,6 @@
 cover
 xblock_utils.egg-info
 tests.integration.*.png
+.idea/
+.tox/
+var/

.travis.yml

@@ -2,25 +2,26 @@ language: python
 addons:
     firefox: "52.0esr"
 python:
-    - "2.7"
+    - 2.7
 before_install:
     - "export DISPLAY=:99"
     - "sh -e /etc/init.d/xvfb start"
 install:
-    - "pip install -e git://github.com/edx/xblock-sdk.git@22c1b2f173919bef22f2d9d9295ec5396d02dffd#egg=xblock-sdk"
-    - "pip install -r $VIRTUAL_ENV/src/xblock-sdk/requirements/base.txt"
-    - "pip install -r $VIRTUAL_ENV/src/xblock-sdk/requirements/test.txt"
-    - "pip install -r requirements.txt"
-    - "pip install -r test_requirements.txt"
     - "mkdir var"
     - "wget https://github.com/mozilla/geckodriver/releases/download/v0.15.0/geckodriver-v0.15.0-linux64.tar.gz"
     - "mkdir geckodriver"
     - "tar -xzf geckodriver-v0.15.0-linux64.tar.gz -C geckodriver"
     - "export PATH=$PATH:$PWD/geckodriver"
+    - "pip install tox"
+env:
+    - TOX_ENV=django18
+    - TOX_ENV=django111
+matrix:
+  include:
+    - python: 2.7
+      env: TOX_ENV=quality
 script:
-    - pep8 xblockutils --max-line-length=120
-    - pylint xblockutils
-    - python run_tests.py --with-coverage --cover-package=xblockutils
+    - tox -e $TOX_ENV
 notifications:
   email: false
 branches:

test_requirements.txt

 ddt
-mock
\ No newline at end of file
+mock
+fs<2

tox.ini

+[tox]
+envlist = py{27}-django{18,111}
+
+# The ordering of deps and commands here is weird due to the way we install xblock-sdk and associated dependencies.
+# Installing test/base.txt inside deps fails, and installing the env-specific Django versions inside deps
+# causes Django 1.4 to be installed over it by something later in the process.
+[base]
+deps =
+    -rrequirements.txt
+    -rtest_requirements.txt
+    -egit+https://github.com/edx/xblock-sdk.git#egg=xblock-sdk
+commands =
+    pip install -r {envdir}/src/xblock-sdk/requirements/test.txt
+    pip install -r {envdir}/src/xblock-sdk/requirements/base.txt
+
+[testenv]
+passenv = CI TRAVIS TRAVIS_* DISPLAY
+deps =
+    {[base]deps}
+commands =
+    {[base]commands}
+    django18: pip install Django>=1.8,<1.9
+    django110: pip install Django>=1.10,<1.11
+    django111: pip install Django>=1.11,<2.0
+    python ./run_tests.py --with-coverage --cover-package=xblockutils
+
+[testenv:quality]
+basepython = python2.7
+deps =
+    {[base]deps}
+commands =
+    {[base]commands}
+    pip install Django>=1.11,<2.0
+    pep8 xblockutils --max-line-length=120
+    pylint xblockutils

xblockutils/settings.py

@@ -35,8 +35,7 @@ class XBlockWithSettingsMixin(object):
         settings_service = self.runtime.service(self, "settings")
         if settings_service:
             return settings_service.get_settings_bucket(self, default=default)
-        else:
-            return default
+        return default
 
 
 class ThemableXBlockMixin(object):

xblockutils/studio_editable.py

@@ -317,8 +317,7 @@ class StudioContainerXBlockMixin(object):
         if root_xblock and root_xblock.location == self.location:
             # User has clicked the "View" link. Show an editable preview of this block's children
             return self.author_edit_view(context)
-        else:
-            return self.author_preview_view(context)
+        return self.author_preview_view(context)
 
     def author_edit_view(self, context):
         """