def scm(self):
        # Lazily initialize SCM to not error-out before command line parsing (or when running non-scm commands).
        original_cwd = os.path.abspath(".")
        if not self._scm:
            self._scm = detect_scm_system(original_cwd)

        if not self._scm:
            script_directory = os.path.abspath(sys.path[0])
            self._scm = detect_scm_system(script_directory)
            if self._scm:
                log("The current directory (%s) is not a WebKit checkout, using %s" % (original_cwd, self._scm.checkout_root))
            else:
                error("FATAL: Failed to determine the SCM system for either %s or %s" % (original_cwd, script_directory))

        return self._scm

 def setUp(self):
     SVNTestRepository.setup(self)
     self._setup_git_clone_of_svn_repository()
     os.chdir(self.git_checkout_path)
     self.scm = detect_scm_system(self.git_checkout_path)
     # For historical reasons, we test some checkout code here too.
     self.checkout = Checkout(self.scm)

def default_out_dir():
    current_scm = scm.detect_scm_system(os.path.dirname(sys.argv[0]))
    if not current_scm:
        return os.getcwd()
    root_dir = current_scm.checkout_root
    if not root_dir:
        return os.getcwd()
    out_dir = os.path.join(root_dir, "LayoutTests/fast/canvas/webgl")
    if os.path.isdir(out_dir):
        return out_dir
    return os.getcwd()