Repository navigation
meta.find_undeclared_variables returning variables set in if blocks as of 3.1.5 #2069
Description
I've observed a change in behaviour between 3.1.4 and 3.1.5 where meta.find_undeclared_variables is now returning variables that are set in all branches of an if statement.
For example with the following:
from jinja2 import Environment, meta
env = Environment()
template = """\
{% if control == 'something' %}
{% set output = 1 %}
{% elif control == 'something else' %}
{% set output = 2 %}
{% else %}
{% set output = 3 %}
{% endif %}
{{ output }}
"""
result = meta.find_undeclared_variables(env.parse(template))
assert result == {'control'}With jinja2 version 3.1.4, this runs without error. With jinja2 version 3.1.5, this errors becasue result contains both "control" and "output". I believe the 3.1.4 behaviour is correct in this instance.
Reading the changelog, I suspect that the fix for #1253 (PR #1665) looks likely to be the cause of this change.
Environment:
- Python version: 3.10.12
- Jinja version: 3.1.5
Activity
alext commentedon Jan 10, 2025
I've just tested using jinja2 3.1.5 with the changes from #1665 reverted, and this results in the same behaviour as 3.1.4.
davidism commentedon Mar 5, 2025
I'm happy to review a PR or suggested fix.
sjrl commentedon Nov 18, 2025
I was running into this issue as well in deepset-ai/haystack#9916 and I was hoping rolling back to 3.1.4 would fix my issue as mentioned here in this thread.
Unfortunately, I found that 3.1.4 still has an issue. If you modify the original example by removing the elif branch and only keeping one if statement then the variable
outputis returned bymeta.find_undeclared_variables(env.parse(template)).Environment