Created attachment 3548
Patch to check $wgArticle is defined.

Patch, as described above.

Attached:

robchur wrote:

Parser hook extensions should not be touching globals such as $wgOut, $wgTitle
or $wgArticle, because parse operations can be called in situations where these
are not defined, e.g. job queue.

Then how should a parser-hook redirect to an error page?

It must not do so.

(You _might_ be able to get away with adding a header field in the parser output
object in 1.10, however I would recommend against such a thing. The concept
appears to be fundamentally flawed, and you should consider a different way of
displaying your error message -- for instance returning error text into the
page, which will not disrupt the entire wiki when you have a localized problem.)

The hook works like this: <protect>bob,john</protect> will prevent the page from
being viewable by anyone except bob and john. I am aware of the issues
regarding MW security, and how easy this is to bypass, but for my trusted
user-base a simple 'keep out' notice such as this is sufficient.

Previously it called the error page to generate a 'protected page' error
message. This works fine in 1.5.8 (and maybe higher) but is now broken. It
would be fixed by a simple check that $wgArticle is actually a valid object...

If you can suggest an alternative way to replace the entire page output (not
just the content within the tags) then that would be sufficient, however I was
under the impression that you could only modify the tag text itself. Feel free
to take this to private e-mail if this is an inappropriate place to continue the
discussion.

Pages may be rendered in batch processing or at many other times. Parsing/HTML rendering is not a UI operation, and must not attempt to manipulate the UI which may be completely unrelated.

To change page permissions, you should be hooking into the permissions system; see hooks in the Title and User classes.

Understood. I have written a new version using the userCan hook and it seems to be working well.

Thanks for taking the time to elaborate.