hgweb: stop passing req and tmpl into @webcommand functions (API) We have effectively removed all consumers of the old wsgirequest type. The templater can be accessed on the requestcontext passed into the @webcommand function. For the most part, these arguments are unused. They only exist to provide backwards compatibility. And in the case of wsgirequest, use of that object could actively interfere with the new request object. So let's stop passing these objects to @webcommand functions. With this commit, wsgirequest is practically dead from the hgweb WSGI application. There are still some uses in hgwebdir though... .. api:: @webcommand functions now only receive a single argument. The request and templater instances can be accessed via the ``req`` and ``templater`` attributes of the first argument. Note that the request object is different from previous Mercurial releases and consumers of the previous ``req`` 2nd argument will need updating to use the new API. Differential Revision: https://phab.mercurial-scm.org/D2803

# A dummy extension that installs an hgweb command that throws an Exception.

from __future__ import absolute_import

from mercurial.hgweb import (
    webcommands,
)

def raiseerror(web):
    '''Dummy web command that raises an uncaught Exception.'''

    # Simulate an error after partial response.
    if 'partialresponse' in web.req.qsparams:
        web.res.status = b'200 Script output follows'
        web.res.headers[b'Content-Type'] = b'text/plain'
        web.res.setbodywillwrite()
        list(web.res.sendresponse())
        web.res.getbodyfile().write(b'partial content\n')

    raise AttributeError('I am an uncaught error!')

def extsetup(ui):
    setattr(webcommands, 'raiseerror', raiseerror)
    webcommands.__all__.append('raiseerror')