tests/test-trusted.py

branchmap: skip obsolete revisions while computing heads

It's time to make this part of core Mercurial obsolescence-aware.

Not considering obsolete revisions when computing heads is clearly what
Mercurial should do. But there are a couple of small issues:

- Let's say tip of the repo is obsolete. There are two ways of finding tiprev
  for branchcache (both are in use): looking at input data for update() and
  looking at computed heads after update(). Previously, repo tip would be
  tiprev of the branchcache. With this patch, an obsolete revision can no
  longer be tiprev. And depending on what way we use for finding tiprev (input
  data vs computed heads) we'll get a different result. This is relevant when
  recomputing cache key from cache contents, and may lead to updating cache for
  obsolete revisions multiple times (not from scratch, because it still would
  be considered valid for a subset of revisions in the repo).

- If all commits on a branch are obsolete, the branchcache will include that
  branch, but the list of heads will be empty (that's why there's now `if not
  heads` when recomputing tiprev/tipnode from cache contents). Having an entry
  for every branch is currently required for notify extension (and
  test-notify.t to pass), because notify doesn't handle revsets in its
  subscription config very well and will throw an error if e.g. a branch
  doesn't exist.

- Cloning static HTTP repos may try to stat() a non-existent obsstore file. The
  issue is that we now care about obsolescence during clone, but statichttpvfs
  doesn't implement a stat method, so a regular vfs.stat() is used, and it
  assumes that file is local and calls os.stat().  During a clone, we're trying
  to stat() .hg/store/obsstore, but in static HTTP case we provide a literal
  URL to the obsstore file on the remote as if it were a local file path. On
  windows it actually results in a failure in test-static-http.t.

The first issue is going to be addressed in a series dedicated to making sure
branchcache is properly and timely written on disk (it wasn't perfect even
before this patch, but there aren't enough tests to demonstrate that). The
second issue will be addressed in a future patch for notify extension that will
make it not raise an exception if a branch doesn't exist. And the third one was
partially addressed in the previous patch in this series and will be properly
fixed in a future patch when this series is accepted.

filteredhash() grows a keyword argument to make sure that branchcache is also
invalidated when there are new obsolete revisions in its repo view. This way
the on-disk cache format is unchanged and compatible between versions (although
it will obviously be recomputed when switching versions before/after this patch
and the repo has obsolete revisions).

There's one test that uses plain `hg up` without arguments while updated to a
pruned commit. To make this test pass, simply return current working directory
parent. Later in this series this code will be replaced by what prune command
does: updating to the closest non-obsolete ancestor.

Test changes:

test-branch-change.t: update branch head and cache update message. The head of
default listed in hg heads is changed because revision 2 was rewritten as 7,
and 1 is the closest ancestor on the same branch, so it's the head of default
now.

The cache invalidation message appears now because of the cache hash change,
since we're now accounting for obsolete revisions. Here's some context:

"served.hidden" repo filter means everything is visible (no filtered
revisions), so before this series branch2-served.hidden file would not contain
any cache hash, only revnum and node. Now it also has a hash when there are
obsolete changesets in the repo. The command that the message appears for is
changing branch of 5 and 6, which are now obsolete, so the cache hash changes.

In general, when cache is simply out-of-date, it can be updated using the old
version as a base. But if cache hash differs, then the cache for that
particular repo filter is recomputed (at least with the current
implementation). This is what happens here.

test-obsmarker-template.t: the pull reports 2 heads changed, but after that the
repo correctly sees only 1. The new message could be better, but it's still an
improvement over the previous one where hg pull suggested merging with an
obsolete revision.

test-obsolete.t: we can see these revisions in hg log --hidden, but they
shouldn't be considered heads even with --hidden.

test-rebase-obsolete{,2}.t: there were new heads created previously after
making new orphan changesets, but they weren't detected. Now we are properly
detecting and reporting them.

test-rebase-obsolete4.t: there's only one head now because the other head is
pruned and was falsely reported before.

test-static-http.t: add obsstore to the list of requested files. This file
doesn't exist on the remotes, but clients want it anyway (they get 404). This
is fine, because there are other nonexistent files that clients request, like
.hg/bookmarks or .hg/cache/tags2-served.

Differential Revision: https://phab.mercurial-scm.org/D12097

# Since it's not easy to write a test that portably deals
# with files from different users/groups, we cheat a bit by
# monkey-patching some functions in the util module

from __future__ import absolute_import, print_function

import os
import sys

from mercurial import (
    error,
    pycompat,
    ui as uimod,
    util,
)
from mercurial.utils import stringutil

hgrc = os.environ['HGRCPATH']
f = open(hgrc, 'rb')
basehgrc = f.read()
f.close()


def _maybesysstr(v):
    if isinstance(v, bytes):
        return pycompat.sysstr(v)
    return pycompat.sysstr(stringutil.pprint(v))


def bprint(*args, **kwargs):
    print(
        *[_maybesysstr(a) for a in args],
        **{k: _maybesysstr(v) for k, v in kwargs.items()}
    )
    # avoid awkward interleaving with ui object's output
    sys.stdout.flush()


def testui(
    user=b'foo',
    group=b'bar',
    tusers=(),
    tgroups=(),
    cuser=b'foo',
    cgroup=b'bar',
    debug=False,
    silent=False,
    report=True,
):
    # user, group => owners of the file
    # tusers, tgroups => trusted users/groups
    # cuser, cgroup => user/group of the current process

    # write a global hgrc with the list of trusted users/groups and
    # some setting so that we can be sure it was read
    f = open(hgrc, 'wb')
    f.write(basehgrc)
    f.write(b'\n[paths]\n')
    f.write(b'global = /some/path\n\n')

    if tusers or tgroups:
        f.write(b'[trusted]\n')
        if tusers:
            f.write(b'users = %s\n' % b', '.join(tusers))
        if tgroups:
            f.write(b'groups = %s\n' % b', '.join(tgroups))
    f.close()

    # override the functions that give names to uids and gids
    def username(uid=None):
        if uid is None:
            return cuser
        return user

    util.username = username

    def groupname(gid=None):
        if gid is None:
            return b'bar'
        return group

    util.groupname = groupname

    def isowner(st):
        return user == cuser

    util.isowner = isowner

    # try to read everything
    # print '# File belongs to user %s, group %s' % (user, group)
    # print '# trusted users = %s; trusted groups = %s' % (tusers, tgroups)
    kind = (b'different', b'same')
    who = (b'', b'user', b'group', b'user and the group')
    trusted = who[(user in tusers) + 2 * (group in tgroups)]
    if trusted:
        trusted = b', but we trust the ' + trusted
    bprint(
        b'# %s user, %s group%s'
        % (kind[user == cuser], kind[group == cgroup], trusted)
    )

    u = uimod.ui.load()
    # disable the configuration registration warning
    #
    # the purpose of this test is to check the old behavior, not to validate the
    # behavior from registered item. so we silent warning related to unregisted
    # config.
    u.setconfig(b'devel', b'warn-config-unknown', False, b'test')
    u.setconfig(b'devel', b'all-warnings', False, b'test')
    u.setconfig(b'ui', b'debug', pycompat.bytestr(bool(debug)))
    u.setconfig(b'ui', b'report_untrusted', pycompat.bytestr(bool(report)))
    u.readconfig(b'.hg/hgrc')
    if silent:
        return u
    bprint(b'trusted')
    for name, path in u.configitems(b'paths'):
        bprint(b'   ', name, b'=', util.pconvert(path))
    bprint(b'untrusted')
    for name, path in u.configitems(b'paths', untrusted=True):
        bprint(b'.', end=b' ')
        u.config(b'paths', name)  # warning with debug=True
        bprint(b'.', end=b' ')
        u.config(b'paths', name, untrusted=True)  # no warnings
        bprint(name, b'=', util.pconvert(path))
    print()

    return u


os.mkdir(b'repo')
os.chdir(b'repo')
os.mkdir(b'.hg')
f = open(b'.hg/hgrc', 'wb')
f.write(b'[paths]\n')
f.write(b'local = /another/path\n\n')
f.close()

# print '# Everything is run by user foo, group bar\n'

# same user, same group
testui()
# same user, different group
testui(group=b'def')
# different user, same group
testui(user=b'abc')
# ... but we trust the group
testui(user=b'abc', tgroups=[b'bar'])
# different user, different group
testui(user=b'abc', group=b'def')
# ... but we trust the user
testui(user=b'abc', group=b'def', tusers=[b'abc'])
# ... but we trust the group
testui(user=b'abc', group=b'def', tgroups=[b'def'])
# ... but we trust the user and the group
testui(user=b'abc', group=b'def', tusers=[b'abc'], tgroups=[b'def'])
# ... but we trust all users
bprint(b'# we trust all users')
testui(user=b'abc', group=b'def', tusers=[b'*'])
# ... but we trust all groups
bprint(b'# we trust all groups')
testui(user=b'abc', group=b'def', tgroups=[b'*'])
# ... but we trust the whole universe
bprint(b'# we trust all users and groups')
testui(user=b'abc', group=b'def', tusers=[b'*'], tgroups=[b'*'])
# ... check that users and groups are in different namespaces
bprint(b"# we don't get confused by users and groups with the same name")
testui(user=b'abc', group=b'def', tusers=[b'def'], tgroups=[b'abc'])
# ... lists of user names work
bprint(b"# list of user names")
testui(
    user=b'abc',
    group=b'def',
    tusers=[b'foo', b'xyz', b'abc', b'bleh'],
    tgroups=[b'bar', b'baz', b'qux'],
)
# ... lists of group names work
bprint(b"# list of group names")
testui(
    user=b'abc',
    group=b'def',
    tusers=[b'foo', b'xyz', b'bleh'],
    tgroups=[b'bar', b'def', b'baz', b'qux'],
)

bprint(b"# Can't figure out the name of the user running this process")
testui(user=b'abc', group=b'def', cuser=None)

bprint(b"# prints debug warnings")
u = testui(user=b'abc', group=b'def', cuser=b'foo', debug=True)

bprint(b"# report_untrusted enabled without debug hides warnings")
u = testui(user=b'abc', group=b'def', cuser=b'foo', report=False)

bprint(b"# report_untrusted enabled with debug shows warnings")
u = testui(user=b'abc', group=b'def', cuser=b'foo', debug=True, report=False)

bprint(b"# ui.readconfig sections")
filename = b'foobar'
f = open(filename, 'wb')
f.write(b'[foobar]\n')
f.write(b'baz = quux\n')
f.close()
u.readconfig(filename, sections=[b'foobar'])
bprint(u.config(b'foobar', b'baz'))

print()
bprint(b"# read trusted, untrusted, new ui, trusted")
u = uimod.ui.load()
# disable the configuration registration warning
#
# the purpose of this test is to check the old behavior, not to validate the
# behavior from registered item. so we silent warning related to unregisted
# config.
u.setconfig(b'devel', b'warn-config-unknown', False, b'test')
u.setconfig(b'devel', b'all-warnings', False, b'test')
u.setconfig(b'ui', b'debug', b'on')
u.readconfig(filename)
u2 = u.copy()


def username(uid=None):
    return b'foo'


util.username = username
u2.readconfig(b'.hg/hgrc')
bprint(b'trusted:')
bprint(u2.config(b'foobar', b'baz'))
bprint(b'untrusted:')
bprint(u2.config(b'foobar', b'baz', untrusted=True))

print()
bprint(b"# error handling")


def assertraises(f, exc=error.Abort):
    try:
        f()
    except exc as inst:
        bprint(b'raised', inst.__class__.__name__)
    else:
        bprint(b'no exception?!')


bprint(b"# file doesn't exist")
os.unlink(b'.hg/hgrc')
assert not os.path.exists(b'.hg/hgrc')
testui(debug=True, silent=True)
testui(user=b'abc', group=b'def', debug=True, silent=True)

print()
bprint(b"# parse error")
f = open(b'.hg/hgrc', 'wb')
f.write(b'foo')
f.close()

try:
    testui(user=b'abc', group=b'def', silent=True)
except error.ConfigError as inst:
    bprint(inst.format())

try:
    testui(debug=True, silent=True)
except error.ConfigError as inst:
    bprint(inst.format())

print()
bprint(b'# access typed information')
with open(b'.hg/hgrc', 'wb') as f:
    f.write(
        b'''\
[foo]
sub=main
sub:one=one
sub:two=two
path=monty/python
bool=true
int=42
bytes=81mb
list=spam,ham,eggs
'''
    )
u = testui(user=b'abc', group=b'def', cuser=b'foo', silent=True)


def configpath(section, name, default=None, untrusted=False):
    path = u.configpath(section, name, default, untrusted)
    if path is None:
        return None
    return util.pconvert(path)


bprint(b'# suboptions, trusted and untrusted')
trusted = u.configsuboptions(b'foo', b'sub')
untrusted = u.configsuboptions(b'foo', b'sub', untrusted=True)
bprint(
    (trusted[0], sorted(trusted[1].items())),
    (untrusted[0], sorted(untrusted[1].items())),
)
bprint(b'# path, trusted and untrusted')
bprint(configpath(b'foo', b'path'), configpath(b'foo', b'path', untrusted=True))
bprint(b'# bool, trusted and untrusted')
bprint(
    u.configbool(b'foo', b'bool'), u.configbool(b'foo', b'bool', untrusted=True)
)
bprint(b'# int, trusted and untrusted')
bprint(
    u.configint(b'foo', b'int', 0),
    u.configint(b'foo', b'int', 0, untrusted=True),
)
bprint(b'# bytes, trusted and untrusted')
bprint(
    u.configbytes(b'foo', b'bytes', 0),
    u.configbytes(b'foo', b'bytes', 0, untrusted=True),
)
bprint(b'# list, trusted and untrusted')
bprint(
    u.configlist(b'foo', b'list', []),
    u.configlist(b'foo', b'list', [], untrusted=True),
)