templates: add filter to reverse list
The filter supports only lists because for lists, it’s straightforward to
implement. Reversing text doesn’t seem very useful and is hard to implement.
Reversing the bytes would break multi-bytes encodings. Reversing the code
points would break characters consisting of multiple code points. Reversing
graphemes is non-trivial without using a library not included in the standard
library.
# A dummy extension that installs an hgweb command that throws an Exception.
from mercurial.hgweb import webcommands
def raiseerror(web):
'''Dummy web command that raises an uncaught Exception.'''
# Simulate an error after partial response.
if b'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(b'raiseerror')