git module vs command module

[Mauricio Tavares]

So I am using the git module to get two packages I am building
locally. First one, a library, I download and then run the make module
and built it (without installing. I will include the library as is).
That works fine. I can run the playbook all day and it will not try to
reinstall or recompile unless there is something new.

The second package I also get using the git module,

- name: Download thing
git:
repo: https://github.com/example/thing
dest: "{{ dev_dir }}/thingi"

Like the email I posted earlier today, I configure the thing (I
decided to break it apart):

- name: configure thing build
command:
cmd: ./configure --with_that-lib=/path/to/the/lib
args:
chdir: dev/thing

Let's ignore building the thing for now. When I run the playbook for
the first time, thing is downloaded and configured. When I run it the
second time, it fails in the download task. The error I am getting is

"Local modifications exist in repository (force=no)."

What would be the best way to deal with this? I did try adding

separate_git_dir: "{{ dev_dir }}/thing.git"

thinking that all it wanted is to have a git dir separate from the dir
I am using to build it, but no dice.

[Mauricio Tavares]

Update: https://stackoverflow.com/questions/41178361/how-to-use-ansible-git-module-pull-a-branch-with-local-changes
showed me what was going on. Thanks for all the help!