add more tests

.travis.yml

@@ -6,10 +6,8 @@ python:
   - "3.6"
   - "nightly"
 install:
-  - "pip install pycodestyle"
-  - "pip install nose"
-  - "pip install coverage"
-  - "pip install coveralls"
+  - "pip install pip --upgrade"
+  - "pip install -r tests-requirements.txt"
   - "pip install -r requirements.txt"
 script:
   ./tests.sh

tests-requirements.txt

@@ -0,0 +1,5 @@
+pycodestyle; python_version >= '3.0'
+pyflakes; python_version >= '3.0'
+nose; python_version >= '3.0'
+coverage; python_version >= '3.0'
+coveralls; python_version >= '3.0'

tests.sh

@@ -7,4 +7,8 @@ set -ev
 
 pycodestyle --ignore=W605 catcli/
 pycodestyle tests/
+
+pyflakes catcli/
+pyflakes tests/
+
 PYTHONPATH=catcli python3 -m nose -s --with-coverage --cover-package=catcli