- Add assertion to verify that the ansible_lsb facts are present.

tasks/main.yml

@@ -5,6 +5,7 @@
   assert:
     that:
         - ansible_os_family == 'Debian'
+        - ansible_lsb is mapping
         - ansible_lsb.codename in ['buster', 'jessie', 'sid', 'stretch', 'trusty', 'xenial', 'yakkety', 'zesty']
         - nodejs_version in [6, 8]