tests: add tests and document expectations from visit_children_set in rust
The tests this patch are adding have the form of formal spec in
invariants::visit_children_set::holds,
and then a series of checks that all examples must satisfy this
formal spec.
I tried to make the spec consistent with how this function is used
and how it was originally conceived. This is in conflict with how it's
documented in Rust. Some of the implementations also fail to implement
this spec, which leads to bugs, in particular when complicated patterns
are used with `hg status`.
# sshprotoext.py - Extension to test behavior of SSH protocol
#
# Copyright 2018 Gregory Szorc <gregory.szorc@gmail.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
# This extension replaces the SSH server started via `hg serve --stdio`.
# The server behaves differently depending on environment variables.
from mercurial import (
error,
extensions,
registrar,
sshpeer,
wireprotoserver,
wireprotov1server,
)
configtable = {}
configitem = registrar.configitem(configtable)
configitem(b'sshpeer', b'mode', default=None)
configitem(b'sshpeer', b'handshake-mode', default=None)
class bannerserver(wireprotoserver.sshserver):
"""Server that sends a banner to stdout."""
def serve_forever(self):
for i in range(10):
self._fout.write(b'banner: line %d\n' % i)
super(bannerserver, self).serve_forever()
class prehelloserver(wireprotoserver.sshserver):
"""Tests behavior when connecting to <0.9.1 servers.
The ``hello`` wire protocol command was introduced in Mercurial
0.9.1. Modern clients send the ``hello`` command when connecting
to SSH servers. This mock server tests behavior of the handshake
when ``hello`` is not supported.
"""
def serve_forever(self):
l = self._fin.readline()
assert l == b'hello\n'
# Respond to unknown commands with an empty reply.
wireprotoserver._sshv1respondbytes(self._fout, b'')
l = self._fin.readline()
assert l == b'between\n'
proto = wireprotoserver.sshv1protocolhandler(
self._ui, self._fin, self._fout
)
rsp = wireprotov1server.dispatch(self._repo, proto, b'between')
wireprotoserver._sshv1respondbytes(self._fout, rsp.data)
super(prehelloserver, self).serve_forever()
def performhandshake(orig, ui, stdin, stdout, stderr):
"""Wrapped version of sshpeer._performhandshake to send extra commands."""
mode = ui.config(b'sshpeer', b'handshake-mode')
if mode == b'pre-no-args':
ui.debug(b'sending no-args command\n')
stdin.write(b'no-args\n')
stdin.flush()
return orig(ui, stdin, stdout, stderr)
elif mode == b'pre-multiple-no-args':
ui.debug(b'sending unknown1 command\n')
stdin.write(b'unknown1\n')
ui.debug(b'sending unknown2 command\n')
stdin.write(b'unknown2\n')
ui.debug(b'sending unknown3 command\n')
stdin.write(b'unknown3\n')
stdin.flush()
return orig(ui, stdin, stdout, stderr)
else:
raise error.ProgrammingError(b'unknown HANDSHAKECOMMANDMODE: %s' % mode)
def extsetup(ui):
# It's easier for tests to define the server behavior via environment
# variables than config options. This is because `hg serve --stdio`
# has to be invoked with a certain form for security reasons and
# `dummyssh` can't just add `--config` flags to the command line.
servermode = ui.environ.get(b'SSHSERVERMODE')
if servermode == b'banner':
wireprotoserver.sshserver = bannerserver
elif servermode == b'no-hello':
wireprotoserver.sshserver = prehelloserver
elif servermode:
raise error.ProgrammingError(b'unknown server mode: %s' % servermode)
peermode = ui.config(b'sshpeer', b'mode')
if peermode == b'extra-handshake-commands':
extensions.wrapfunction(sshpeer, '_performhandshake', performhandshake)
elif peermode:
raise error.ProgrammingError(b'unknown peer mode: %s' % peermode)