final fix

Author: tqchen

tests/travis/setup.sh

@@ -9,6 +9,8 @@ if [ ${TRAVIS_OS_NAME} == "osx" ]; then
     fi
 fi
 
-if [ ${TASK} == "lint" ]; then
-    pip install --user cpplint 'pylint==1.4.4' 'astroid==1.3.6'
+if [ ${TASK} == "lint" ] || [ ${TASK} == "all_test" ]; then
+    if [ ! ${TRAVIS_OS_NAME} == "osx" ]; then
+        pip install --user cpplint 'pylint==1.4.4' 'astroid==1.3.6'
+    fi
 fi