role callback dependencies

[Mike Biancaniello]

So I have been playing around with multiple callbacks and ordering. I created two callback plugins: calltest1, calltest2. Each one simply prints its number and fcn to the screen:

e.g.

TEST1: v2_playbook_on_start()
TEST2: v2_playbook_on_start()

Some observations:
1. If I put the callbacks in ./callback_plugins, I cannot choose the order at runtime. I assume they run in ABC order.
2. If I put the callbacks in separate roles, (roles/calltest1/callback_plugins, roles/calltest2/callback_plugins/ respectively), then I can control the ordering by calling roles:

file: calltestsite.yml

---
roles:
- calltest2
- calltest1

output:

TEST2: v2_playbook_on_start()
TEST1: v2_playbook_on_start()

3. However, and this is where it gets weird:
If I set calltest2 as a dependency of calltest1, calltest1 fires first!
file: roles/calltest1/meta/main.yml

---
dependencies:
  - { role: calltest2 }

file: calltestsite.yml

---
roles:
- calltest1

output:

TEST1: v2_playbook_on_start()
TEST2: v2_playbook_on_start()

4. what's really weird is that I know for sure that calltest2 is actually running first:
file: roles/calltest1/tasks/main.yml

---
- name: calltest1 show me role task
  debug: var="calltest1 role task"

file: roles/calltest1/tasks/main.yml

---
- name: calltest1 show me role task
  debug: var="calltest1 role task"

output:

TASK [calltest2 : calltest2 show me role task] *********************************
TEST1: v2_runner_on_ok()
TEST2: v2_runner_on_ok()

TEST1: v2_playbook_on_task_start()
TEST2: v2_playbook_on_task_start()

TASK [calltest1 : calltest1 show me role task] *********************************
TEST1: v2_runner_on_ok()
TEST2: v2_runner_on_ok()

Is this expected behavior?

(fwiw, I'm not planning on listing callback dependencies, but thought the behavior was curious)