This fixes a corner case where ini files live in a subdir
of the main inventory directory.
Reproducing the original error:
mkdir -p inventory/ini
cat > inventory/ini/hosts << EOF
[www]
www1
EOF
$ ansible -i inventory/ all -m ping
ERROR! 'all'
(or without the [www] group, it would complain about 'ungrouped')
Required some rewiring in inventory code to make sure we're using
the DataLoader class for some data file operations, which makes mocking
them much easier.
Also identified two corner cases not currently handled by the code, related
to inventory variable sources and which one "wins". Also noticed we weren't
properly merging variables from multiple group/host_var file locations
(inventory directory vs. playbook directory locations) so fixed as well.
In some cases, where a host is mentioned in multiple groups, and those
groups are referenced in multiple ini files, a group could still contain
multiple instances of a group in its host,groups list, where only one of them
is the right group, that exists in the inventory.
Make sure all hosts and groups are unique objects
and that those are referenced uniquely everywhere.
Also fixes test_dir_inventory unit tests which were broken after previous
patches.
modified: lib/ansible/inventory/dir.py