tests/hgweberror.py

util: make sortdict.keys() return a copy

dict.keys() is documented to return a copy, so it's surprising that
sortdict.keys() did not. I noticed this because we have an extension
that calls readlocaltags(). That method tries to remove any tags that
point to non-existent revisions (most likely stripped). However, since
it's unintentionally working on the instance it's modifying, it
sometimes fails to remove tags when there are multiple bad tags in a
row. This was not caught because localrepo.tags() does an additional
layer of filtering.

sortdict is also used in other places, but I have not checked whether
its keys() and/or __delitem__() methods are used there.

# 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, req, tmpl):
    '''Dummy web command that raises an uncaught Exception.'''

    # Simulate an error after partial response.
    if 'partialresponse' in req.form:
        req.respond(200, 'text/plain')
        req.write('partial content\n')

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

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