tests/hgweberror.py

merge: move purge logic from extension

Working directory purging feels like functionality that should be
in core rather than in an extension.

This commit effectively moves the core purging logic from the
purge extension to merge.py.

Code was refactored slightly. Rather than deal with printing in
this function, the function is a generator of paths and the caller
can worry about printing.

Differential Revision: https://phab.mercurial-scm.org/D4477

# 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')