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
37450	Template lexer fails on comment/verbatim tags without whitespace after {%	Spoko Dev	Spoko Dev	"Since 1a9fba7a6c2a0acead19bbb45c25ceb0fdcca7c8 (#23424), `_comment_end_re` and `_verbatim_end_re` in `django/template/base.py` require whitespace after `{%`, so `{%endcomment%}` and `{%endverbatim%}` never close a raw block. `_raw_start_re` requires it too, so with `debug=False` a `{%verbatim%}` block is not lexed as raw text. Django 6.1.2 accepts these tags without the spaces.

On main (3d3d943b74):

{{{#!python
from django.template import Context, Engine

Engine(debug=True).from_string(""{%comment%}hidden{%endcomment%}visible"").render(Context())
# TemplateSyntaxError: Unclosed tag on line 1: 'comment'. Looking for one of: endcomment.

Engine().from_string(""{% comment %}hidden{%endcomment%}visible"").render(Context())
# TemplateSyntaxError: Unclosed tag on line 1: 'comment'. Looking for one of: endcomment.

Engine().from_string(""{%verbatim%}{{ x }}{%endverbatim%}"").render(Context({""x"": 1}))
# AttributeError: 'NoneType' object has no attribute 'engine'
}}}

On 6.1.2 these render `visible`, `visible` and `{{ x }}`. With `debug=False`, `{%comment%}…{%endcomment%}` alone still renders, but it fails as soon as the template also contains `{% comment` anywhere, even inside a `{# #}` comment.

Templates in the wild use this form, for example `templates/releasetext.html` in postgres/pgweb (`{%comment%}…{%endcomment%}`): on main, `DebugLexer` finds no `endcomment` token in it, while 6.1.2 finds one.

`makemessages` is affected as well: with `{% comment %}note{%endcomment%}` before `{% translate ""Welcome"" %}`, `templatize()` no longer outputs `""Welcome""`, so the string is left out of the .po file without an error.

Allowing zero whitespace in the three patterns restores the 6.1.2 behaviour; I have a patch with tests and will open a PR. Open [https://github.com/django/django/pull/21982 PR #21982] changes `_comment_end_re` and `_verbatim_end_re` to `\s+endcomment\s+` / `\s+endverbatim\s+`, which keeps this problem and would also require a space before `%}`.
"	Bug	assigned	Template system	dev	Release blocker				Unreviewed	1	0	0	0	0	0