travis: really check Python3

.travis.yml

@@ -32,16 +32,16 @@ jobs:
   include:
     - dist: xenial
       env: BUILD_WITH_COLLISION_SUPPORT=OFF
-      python: "2.7"
+      python: 2.7
     - dist: trusty 
       env: BUILD_WITH_COLLISION_SUPPORT=ON
-      python: "2.7"
+      python: 2.7
     - dist: xenial
       env: BUILD_WITH_COLLISION_SUPPORT=ON
-      python: "2.7"
+      python: 2.7
     - dist: xenial
       env: BUILD_WITH_COLLISION_SUPPORT=ON
-      python: "3.5"
+      python: 3.5
 
 allow_failures:
   - compiler:

travis_custom/custom_before_install

@@ -14,8 +14,14 @@ sudo free -m -t
 
 # Setup environment variables.
 export APT_DEPENDENCIES="doxygen libboost-system-dev libboost-test-dev libboost-filesystem-dev libboost-program-options-dev libeigen3-dev liburdfdom-dev texlive-font-utils"
+
 # Add Python dependency
-export APT_DEPENDENCIES=$APT_DEPENDENCIES" libboost-python-dev robotpkg-py27-eigenpy python2.7-dev python-numpy"
+echo "TRAVIS_PYTHON_VERSION=$TRAVIS_PYTHON_VERSION"
+if [[ $TRAVIS_PYTHON_VERSION -gt 3 ]]; then
+  export APT_DEPENDENCIES=$APT_DEPENDENCIES" libboost-python-dev robotpkg-py35-eigenpy python3.5-dev python-numpy"
+else
+  export APT_DEPENDENCIES=$APT_DEPENDENCIES" libboost-python-dev robotpkg-py27-eigenpy python2.7-dev python-numpy"
+fi
 
 # Add Geometry dependencies
 if [[ $BUILD_WITH_COLLISION_SUPPORT -eq ON ]]; then