Expected Behavior

In jinja < 2.9, the groupby filter returns its data as a tuple.

Actual Behavior

In jinja >= 2.9, the groupby filter returns its data as a namedtuple.

Template Code

Here's what I'm using along with Ansible right now:

---

- hosts: all
  vars:
    fruits:
      - name: apple
        enjoy: yes
      - name: orange
        enjoy: no
      - name: strawberry
        enjoy: yes
  tasks:

    - name: Loop through my fruits
      debug:
        msg: |
          {% set fruit_list = [] %}
          {% for fruit_dict in item[1] %}
          {{ fruit_dict.name }}
          {% endfor %}
      with_items:
        - "{{ fruits | groupby('enjoy') }}"

In jinja 2.8, the result of the groupby() is a tuple and Ansible is able to parse it with python's AST module without an issue. In jinja 2.9 and later, the groupby() returns a namedtuple and this cannot be parsed with AST. This causes an exception in Ansible.

This may not be considered a bug within jinja, but this change is fairly disruptive for downstream users.

Ansible bug: ansible/ansible#20098

Your Environment

• Python version: 2.7.12
• Jinja version: 2.9.4