Running a macro not within a model (e.g. using dbt run-operation) will fail because macros have no "tags"

[wircho]

Overview

We have a project where we sometimes run dbt run-operation some_macro and the some_macro being run uses ref somewhere inside it. This ends up calling dbt_unit_testing's running_unit_test(), which checks for tags in the config.

This is fine when config is a model's config. But it does not work when no model is being compiled, because in the latter scenario, config has no "tags" at all.

How to reproduce

In a project set up with dbt_unit_testing run:

> dbt run-operation ref --args "model_name: any_existing_model"
...
  argument of type 'NoneType' is not iterable
...

Suggestion 1

My recommendation is to edit this macro:

dbt-unit-testing/macros/tests.sql

Lines 179 to 181 in 3bfdb45

	{% macro running_unit_test() %}
	{{ return ('unit-test' in config.get('tags')) }}
	{% endmacro %}

to this:

{% macro running_unit_test() %}
  {{ return (config.model.resource_type.value == 'model' and 'unit-test' in config.get('tags')) }}
{% endmacro %}

Suggestion 2

A simpler (and arguably safer) solution is:

{% macro running_unit_test() %}
  {{ return (config.get('tags') and 'unit-test' in config.get('tags')) }}
{% endmacro %}