import_task swallows AnsibleParserError

[mdaniel]

SUMMARY

A malformed list item in an included task file yields a cryptic message

ISSUE TYPE

• Bug Report

COMPONENT NAME

lib/ansible/cli/scripts/ansible_cli_stub.py

ANSIBLE VERSION

Confirmed as of c888035

ansible 2.10.0.dev0
  config file = None
  configured module search path = ['/usr/share/ansible/plugins/modules']
  ansible python module location = /proj/ansible/ansible/venv/lib/python3.7/site-packages/ansible_base-2.10.0.dev0-py3.7.egg/ansible
  executable location = /proj/ansible/ansible/venv/bin/ansible
  python version = 3.7.7 (default, Mar 11 2020, 11:44:20) [GCC 9.2.1 20191008]

CONFIGURATION

OS / ENVIRONMENT

STEPS TO REPRODUCE

• bug.yml

---
- oops

• pb.yml

- hosts: all
  gather_facts: no
  tasks:
  - include_tasks: bug.yml

EXPECTED RESULTS

$ ansible-playbook -i localhost, -c local pb.yml
ERROR! Traceback (most recent call last):
  File "/proj/ansible/ansible/lib/ansible/playbook/block.py", line 130, in _load_block
    use_handlers=self._use_handlers,
  File "/proj/ansible/ansible/lib/ansible/playbook/helpers.py", line 106, in load_list_of_tasks
    raise AnsibleAssertionError('The ds (%s) should be a dict but was a %s' % (ds, type(ds)))
ansible.errors.AnsibleAssertionError: The ds (['oops']) should be a dict but was a <class 'list'>

or something similar, because just eating the AnsibleParserError makes tracking down the erroneous list item harder than necessary

ACTUAL RESULTS

$ ansible-playbook -i localhost, -c local -vvvvvvvvv pb.yml
ansible-playbook 2.10.0.dev0
  config file = None
  configured module search path = ['/usr/share/ansible/plugins/modules']
  ansible python module location = /proj/ansible/ansible/lib/ansible
  executable location = /proj/ansible/ansible/venv/bin/ansible-playbook
  python version = 3.7.7 (default, Mar 11 2020, 11:44:20) [GCC 9.2.1 20191008]
No config file found; using defaults
setting up inventory plugins
Set default localhost to localhost
Parsed localhost, inventory source with host_list plugin
statically imported: /proj/ansible/ansible/bug.yml
ERROR! A malformed block was encountered while loading a block

and the same outcome when run with ANSIBLE_DEBUG=1 which was especially surprising

$ ANSIBLE_DEBUG=1 ansible-playbook -i localhost, -c local -vvvvvvvvv pb.yml
## snip
 22539 1585707905.71204: Loading BecomeModule 'sudo' from /proj/ansible/ansible/lib/ansible/plugins/become/sudo.py (found_in_cache=False, class_only=True)
 22539 1585707905.71232: Loading data from /proj/ansible/ansible/bug0.yml
 22539 1585707905.71591: in VariableManager get_vars()
 22539 1585707905.71621: done with get_vars()
 22539 1585707905.71634: Loading data from /proj/ansible/ansible/bug00.yml
statically imported: /proj/ansible/ansible/bug.yml
 22539 1585707905.71686: RUNNING CLEANUP
ERROR! A malformed block was encountered while loading a block

[ansibot]

Files identified in the description:

• lib/ansible/cli/scripts/ansible_cli_stub.py

If these files are incorrect, please update the component name section of the description or use the !component bot command.

click here for bot help

[felixfontein]

This isn't just related to import_task, but happens in general:

- hosts: localhost
  tasks:
    - debug msg=hi

[felixfontein]

See https://app.shippable.com/github/ansible-collections/ansible.posix/runs/456/27/console for a real-life example - every CI run here failed with ERROR! A malformed block was encountered while loading a block without providing any more information. Since the test was just re-enabled in the most recent commit, it took some time to spot the error.