This patch does three major things:
* Merges the django.template.debug implementation into django.template.base.
* Simplifies the debug implementation.
The old implementation copied debug information to every token and node.
The django_template_source attribute was set in multiple places, some
quite hacky, like django.template.defaulttags.ForNode.
Debug information is now annotated in two high-level places:
* Template.compile_nodelist for errors during parsing
* Node.render_annotated for errors during rendering
These were chosen because they have access to the template and context
as well as to all exceptions that happen during either the parse or
render phase.
* Moves the contextual line traceback information creation from
django.views.debug into django.template.base.Template. The debug views now
only deal with the presentation of the debug information.
During the autumn DST change, the template engine would fail to convert
the naive representation of now when USE_TZ = True. Passing now in UTC
eliminates the issue.
Thanks mbertheau and tricoder42.
Refs #23714.
In addition to ImproperlyConfigured, Engine.get_default() may also raise
ImportError or other exceptions. It's better to catch all exceptions in
places where the default engine isn't strictly required.
Passed the engine instance to loaders. This is a prerequisite for
looking up configuration on the engine instance instead of global
settings.
This is backwards incompatible for custom template loaders that override
__init__. However the documentation doesn't talk about __init__ and the
way to pass arguments to custom template loaders isn't specified. I'm
considering it a private API.
Added a class to wrap callable in settings:
* Not to call in the debug page (#21345).
* Not to break the debug page if the callable forbidding to set attributes (#23070).
Thanks @bmispelon for giving me some advice.
Commit 79558c78 cleaned up the (undocumented) interface of Resolver404
exception, which breaks compatibility with code messing with .args[0]
directly. Revert the cleanup part and simply leave the fix itself.
When django.core.urlresolvers.resolve was called from a view, failed
and the exception was propagated and rendered by technical_404_response,
the URL mentioned on the page was the current URL instead of the URL
passed to resolve().
Fixed by using the path attribute from the Resolver404 exception instead
of request.path_info. Also cleaned up the exceptions to use standard
named parameters instead of stuffing a dict in args[0]