In order to run the test suite (without skipping tests) you must ensure you have git, bzr and hg installed on your system - and available in your PATH. You also have to ensure the user is configured for each of these.
This is usually done by editing the config file, but may differ from system to system, as an example you can see how this is done on the travis machines in the .travis.yml file:
git config --global user.email "[email protected]"
git config --global user.name "Your Name"
echo -e "[ui]\nusername = Your Name <[email protected]>" > ~/.hgrc
bzr whoami "Your Name <[email protected]>"