annotate tests/test-trusted.py @ 30435:b86a448a2965

zstd: vendor python-zstandard 0.5.0

As the commit message for the previous changeset says, we wish
for zstd to be a 1st class citizen in Mercurial. To make that
happen, we need to enable Python to talk to the zstd C API. And
that requires bindings.

This commit vendors a copy of existing Python bindings. Why do we
need to vendor? As the commit message of the previous commit says,
relying on systems in the wild to have the bindings or zstd present
is a losing proposition. By distributing the zstd and bindings with
Mercurial, we significantly increase our chances that zstd will
work. Since zstd will deliver a better end-user experience by
achieving better performance, this benefits our users. Another
reason is that the Python bindings still aren't stable and the
API is somewhat fluid. While Mercurial could be coded to target
multiple versions of the Python bindings, it is safer to bundle
an explicit, known working version.

The added Python bindings are mostly a fully-featured interface
to the zstd C API. They allow one-shot operations, streaming,
reading and writing from objects implements the file object
protocol, dictionary compression, control over low-level compression
parameters, and more. The Python bindings work on Python 2.6,
2.7, and 3.3+ and have been tested on Linux and Windows. There are
CFFI bindings, but they are lacking compared to the C extension.
Upstream work will be needed before we can support zstd with PyPy.
But it will be possible.

The files added in this commit come from Git commit
e637c1b214d5f869cf8116c550dcae23ec13b677 from
https://github.com/indygreg/python-zstandard and are added without
modifications. Some files from the upstream repository have been
omitted, namely files related to continuous integration.

In the spirit of full disclosure, I'm the maintainer of the
"python-zstandard" project and have authored 100% of the code
added in this commit. Unfortunately, the Python bindings have
not been formally code reviewed by anyone. While I've tested
much of the code thoroughly (I even have tests that fuzz APIs),
there's a good chance there are bugs, memory leaks, not well
thought out APIs, etc. If someone wants to review the code and
send feedback to the GitHub project, it would be greatly
appreciated.

Despite my involvement with both projects, my opinions of code
style differ from Mercurial's. The code in this commit introduces
numerous code style violations in Mercurial's linters. So, the code
is excluded from most lints. However, some violations I agree with.
These have been added to the known violations ignore list for now.

# 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
from mercurial import (
    error,
    ui as uimod,
    util,
)

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

def testui(user='foo', group='bar', tusers=(), tgroups=(),
           cuser='foo', cgroup='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, 'w')
    f.write(basehgrc)
    f.write('\n[paths]\n')
    f.write('global = /some/path\n\n')

    if tusers or tgroups:
        f.write('[trusted]\n')
        if tusers:
            f.write('users = %s\n' % ', '.join(tusers))
        if tgroups:
            f.write('groups = %s\n' % ', '.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 '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 = ('different', 'same')
    who = ('', 'user', 'group', 'user and the group')
    trusted = who[(user in tusers) + 2*(group in tgroups)]
    if trusted:
        trusted = ', but we trust the ' + trusted
    print('# %s user, %s group%s' % (kind[user == cuser], kind[group == cgroup],
                                     trusted))

    u = uimod.ui()
    u.setconfig('ui', 'debug', str(bool(debug)))
    u.setconfig('ui', 'report_untrusted', str(bool(report)))
    u.readconfig('.hg/hgrc')
    if silent:
        return u
    print('trusted')
    for name, path in u.configitems('paths'):
        print('   ', name, '=', path)
    print('untrusted')
    for name, path in u.configitems('paths', untrusted=True):
        print('.', end=' ')
        u.config('paths', name) # warning with debug=True
        print('.', end=' ')
        u.config('paths', name, untrusted=True) # no warnings
        print(name, '=', path)
    print()

    return u

os.mkdir('repo')
os.chdir('repo')
os.mkdir('.hg')
f = open('.hg/hgrc', 'w')
f.write('[paths]\n')
f.write('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='def')
# different user, same group
testui(user='abc')
# ... but we trust the group
testui(user='abc', tgroups=['bar'])
# different user, different group
testui(user='abc', group='def')
# ... but we trust the user
testui(user='abc', group='def', tusers=['abc'])
# ... but we trust the group
testui(user='abc', group='def', tgroups=['def'])
# ... but we trust the user and the group
testui(user='abc', group='def', tusers=['abc'], tgroups=['def'])
# ... but we trust all users
print('# we trust all users')
testui(user='abc', group='def', tusers=['*'])
# ... but we trust all groups
print('# we trust all groups')
testui(user='abc', group='def', tgroups=['*'])
# ... but we trust the whole universe
print('# we trust all users and groups')
testui(user='abc', group='def', tusers=['*'], tgroups=['*'])
# ... check that users and groups are in different namespaces
print("# we don't get confused by users and groups with the same name")
testui(user='abc', group='def', tusers=['def'], tgroups=['abc'])
# ... lists of user names work
print("# list of user names")
testui(user='abc', group='def', tusers=['foo', 'xyz', 'abc', 'bleh'],
       tgroups=['bar', 'baz', 'qux'])
# ... lists of group names work
print("# list of group names")
testui(user='abc', group='def', tusers=['foo', 'xyz', 'bleh'],
       tgroups=['bar', 'def', 'baz', 'qux'])

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

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

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

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

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

print()
print("# read trusted, untrusted, new ui, trusted")
u = uimod.ui()
u.setconfig('ui', 'debug', 'on')
u.readconfig(filename)
u2 = u.copy()
def username(uid=None):
    return 'foo'
util.username = username
u2.readconfig('.hg/hgrc')
print('trusted:')
print(u2.config('foobar', 'baz'))
print('untrusted:')
print(u2.config('foobar', 'baz', untrusted=True))

print()
print("# error handling")

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

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

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

try:
    testui(user='abc', group='def', silent=True)
except error.ParseError as inst:
    print(inst)

try:
    testui(debug=True, silent=True)
except error.ParseError as inst:
    print(inst)