Ansible tasklist to pull from a github repo, with different behavior in dev vs. production

pull_from_github.yml

---
# This is a *task-level* include
# Invoke it as a task like so
#    - include: "lib/pull_from_github.yml"
#      vars:
#         ...
# where the vars are these:
#   repo=name             required.  name is like "smbbeta_testing"
#   dest=dir              required.  directory for the repo
#   deploy_type=prod|dev  required.  deployment type.
#   branch=name           opt. branch to checkout. default: master
#   owner=username        opt. owner of the directory & files (if not root)
#
# To force a redeploy from scratch, delete the dest directory in a step before this one.

# make sure deploy_type has a legal value.  will also error out on undefined.
- fail: msg="deploy_type must be prod or dev"
  when: deploy_type != 'prod' and deploy_type != 'dev'

# get status of destination directory
- stat: path="{{dest}}"
  register: s

# pieces of the commands we will build
- set_fact:
    repo_exists: "{{ s.stat.isdir is defined and s.stat.isdir }}"
    clone_args: "--depth=1 --no-single-branch"
    pullbranch: "master"

# changing the commands based on supplied branch name
- set_fact:
    clone_args: "{{clone_args}} -b {{branch}}"
    pullbranch: "{{branch}}"
  when: branch is defined and branch and branch != 'master'

# build command in one of three cases:
# case 1: update prod.  overrides any changed files --- forcible reset.
# (note: the combination of checkout and reset in that order make sure we are on the right branch, and
# the right commit of that branch; doesn't seem like there's a single git command that does this, which is odd)
- set_fact:
    gh_command: "cd {{dest}}; git fetch; git checkout -f {{pullbranch}}; git reset --hard origin/{{pullbranch}}"
  when: repo_exists and deploy_type == 'prod'

# case 2: update dev.  for sanity, this only handles the ff case.  any actual merging is left to the developer.
# also note this case ignores branch parameter --- we don't want to override whatever the developer might be doing.
- set_fact:
    gh_command: "cd {{dest}}; git pull --ff-only"
  when: repo_exists and deploy_type == 'dev'

# case 3: clone (prod or dev)
- set_fact:
    gh_command: "git clone git@github.com:smbmatch/{{repo}}.git {{dest}} {{clone_args}}"
  when: repo_exists == false

- debug: var=gh_command
- shell: "{{gh_command}}"

# yes I know this is an ugly way to do it
- name: restore proper ownership
  file:
    path: "{{dest}}"
    state: directory
    owner: "{{owner}}"
    recurse: yes
  when: owner is defined and owner