id summary reporter owner description type status component version severity resolution keywords cc stage has_patch needs_docs needs_tests needs_better_patch easy ui_ux
27584 Template error raised in a parent template shows incorrect source location on debug page Bob nobody "When an error is raised from a template the django debug page attempts to show the location in the template where the error occurred. When this error occurs in a tag located on a parent template the debug page incorrectly shows the source from the child template instead of the parent.
Using a simple instance of template inheritance:
base.html
{{{
{% load app_tags %}
basic
{% magic %}
banana
{% endmagic %}
{% block fill %}
{% endblock %}
}}}
specific.html
{{{
{% extends ""base.html"" %}
{% block fill %}
something specific
{% endblock fill %}
}}}
And define magic tag to just error
{{{#!python
from django import template
register = template.Library()
@register.tag(name=""magic"")
def do_magic(parser, token):
nodelist = parser.parse(('endmagic',))
parser.delete_first_token()
return MagicNode()
class MagicNode(template.Node):
def render(self, context):
raise template.TemplateSyntaxError('oh dear')
}}}
With debug enabled loading a view that renders the specific.html template generates the debug page which displays
{{{
Error during template rendering
In template /home/bob/code/test-template-tag/testtemplatetag/basic/templates/specific.html, error at line 7
oh dear
}}}
And an excerpt from the specific.html template with line seven highlighted (the text ""something specific""). Instead of the correct line from base.html.
I took a look through the history of the code generating the debug information, I believe it is this change https://github.com/django/django/commit/55f12f8709f0604df7e1817a4c114ead1fb9a311 that has changed the behaviour. Looking at the tags this was included in 1.9, so I checked out 1.8 and it correctly displays the base.html source code and identifies the magic tag as the line triggering the error.
" Bug closed Template system 1.10 Normal fixed Preston Timmons Accepted 1 0 0 0 0 0