image_alt rule fails to find missing alt tag inside django block

[360cid]

Describe the bug

The image_alt rule does not seem to work inside Django template blocks. This seems very similar to #28, but since it's a different rule I wanted to open a separate ticket.

Which terms did you search for in the documentation and issue tracker?

Image_alt, image, alt tag, django

Environment

$ curlylint --version
curlylint, version 0.12.2

MacOS Catalina 10.15.7

Steps to reproduce

1. Create the following template.html:

{% block content %}
    <img src="/path/static/image.png">
{% endblock %}

2. Run curlylint with image_alt enabled:

curlylint --rule 'image_alt: true' template.html

Expected behavior

$ curlylint --rule 'image_alt: true' template.html
template.html
3:5	The `<img>` tag must have a `alt` attribute, either with meaningful text, or an empty string for decorative images	image_alt

Oh no! 💥 💔 💥
1 error reported

Actual behavior

$ curlylint --rule 'image_alt: true' template.html
All done! ✨ 🍰 ✨

The missing alt attribute is reported correctly when the img tag is moved out of the block.

[thibaudcolas]

Thank you @360cid, I wouldn’t be surprised if this was indeed the same issue as #28. Currently it’s not ideal that each rule implements its own parsing of the template’s AST, so it leads to issues like this.

If you want to help fixing this, the first step will be to add a test case for this in https://github.com/thibaudcolas/curlylint/blob/main/curlylint/rules/image_alt/image_alt_test.json.