tests/test-check-interfaces.py

tests: conditionalize tests based on presence of revlogs for files

~85 tests don't like our non-revlog file store for various reasons.

This commit introduces hghave functionality for declaring and querying
repository features. By default, we assume repositories have
revlog-based file storage. But if the HGREPOFEATURES environment
variable is set, we can override the default set of repository
features. If you run the test harness with our simplestorerepo
extension and an environment variable set to the proper value, you
can override the hghave defaults to agree with simplestorerepo's
version of reality.

Various tests have been modified so behavior dependent on revlog-based
file storage is marked as such.

This fixes a handful of test failures with our custom file storage
extension. But dozens remain. The point of this commit is to demonstrate
how tests will need to be modified to account for custom storage
implementations.

TBH, I'm not convinced hghave is the proper layer for repository
feature detection. I /think/ we'll eventually want something in
run-tests.py itself. But that would require inventing a new primitive
in the test harness. This is all very alpha at the moment. So I think
hghave is an acceptable place to hang this feature detection. I think
the right time to be thinking about integrating this into run-tests.py
is *after* we have a stable alternate storage implementation in core.
For now, let's try to make progress towards the idea of an alternate
storage backend.

Differential Revision: https://phab.mercurial-scm.org/D3030

# Test that certain objects conform to well-defined interfaces.

from __future__ import absolute_import, print_function

import os

from mercurial.thirdparty.zope import (
    interface as zi,
)
from mercurial.thirdparty.zope.interface import (
    verify as ziverify,
)
from mercurial import (
    bundlerepo,
    httppeer,
    localrepo,
    repository,
    sshpeer,
    statichttprepo,
    ui as uimod,
    unionrepo,
    wireprotoserver,
    wireprototypes,
)

rootdir = os.path.normpath(os.path.join(os.path.dirname(__file__), '..'))

def checkzobject(o):
    """Verify an object with a zope interface."""
    ifaces = zi.providedBy(o)
    if not ifaces:
        print('%r does not provide any zope interfaces' % o)
        return

    # Run zope.interface's built-in verification routine. This verifies that
    # everything that is supposed to be present is present.
    for iface in ifaces:
        ziverify.verifyObject(iface, o)

    # Now verify that the object provides no extra public attributes that
    # aren't declared as part of interfaces.
    allowed = set()
    for iface in ifaces:
        allowed |= set(iface.names(all=True))

    public = {a for a in dir(o) if not a.startswith('_')}

    for attr in sorted(public - allowed):
        print('public attribute not declared in interfaces: %s.%s' % (
            o.__class__.__name__, attr))

# Facilitates testing localpeer.
class dummyrepo(object):
    def __init__(self):
        self.ui = uimod.ui()
    def filtered(self, name):
        pass
    def _restrictcapabilities(self, caps):
        pass

class dummyopener(object):
    handlers = []

# Facilitates testing sshpeer without requiring an SSH server.
class badpeer(httppeer.httppeer):
    def __init__(self):
        super(badpeer, self).__init__(None, None, None, dummyopener())
        self.badattribute = True

    def badmethod(self):
        pass

class dummypipe(object):
    def close(self):
        pass

def main():
    ui = uimod.ui()
    # Needed so we can open a local repo with obsstore without a warning.
    ui.setconfig('experimental', 'evolution.createmarkers', True)

    checkzobject(badpeer())

    ziverify.verifyClass(repository.ipeerbaselegacycommands,
                         httppeer.httppeer)
    checkzobject(httppeer.httppeer(None, None, None, dummyopener()))

    ziverify.verifyClass(repository.ipeerbase,
                         localrepo.localpeer)
    checkzobject(localrepo.localpeer(dummyrepo()))

    ziverify.verifyClass(repository.ipeerbaselegacycommands,
                         sshpeer.sshv1peer)
    checkzobject(sshpeer.sshv1peer(ui, 'ssh://localhost/foo', None, dummypipe(),
                                   dummypipe(), None, None))

    ziverify.verifyClass(repository.ipeerbaselegacycommands,
                         sshpeer.sshv2peer)
    checkzobject(sshpeer.sshv2peer(ui, 'ssh://localhost/foo', None, dummypipe(),
                                   dummypipe(), None, None))

    ziverify.verifyClass(repository.ipeerbase, bundlerepo.bundlepeer)
    checkzobject(bundlerepo.bundlepeer(dummyrepo()))

    ziverify.verifyClass(repository.ipeerbase, statichttprepo.statichttppeer)
    checkzobject(statichttprepo.statichttppeer(dummyrepo()))

    ziverify.verifyClass(repository.ipeerbase, unionrepo.unionpeer)
    checkzobject(unionrepo.unionpeer(dummyrepo()))

    ziverify.verifyClass(repository.completelocalrepository,
                         localrepo.localrepository)
    repo = localrepo.localrepository(ui, rootdir)
    checkzobject(repo)

    ziverify.verifyClass(wireprototypes.baseprotocolhandler,
                         wireprotoserver.sshv1protocolhandler)
    ziverify.verifyClass(wireprototypes.baseprotocolhandler,
                         wireprotoserver.sshv2protocolhandler)
    ziverify.verifyClass(wireprototypes.baseprotocolhandler,
                         wireprotoserver.httpv1protocolhandler)
    ziverify.verifyClass(wireprototypes.baseprotocolhandler,
                         wireprotoserver.httpv2protocolhandler)

    sshv1 = wireprotoserver.sshv1protocolhandler(None, None, None)
    checkzobject(sshv1)
    sshv2 = wireprotoserver.sshv2protocolhandler(None, None, None)
    checkzobject(sshv2)

    httpv1 = wireprotoserver.httpv1protocolhandler(None, None, None)
    checkzobject(httpv1)
    httpv2 = wireprotoserver.httpv2protocolhandler(None, None)
    checkzobject(httpv2)

main()