view tests/test-url.py @ 39496:2f9f7889549b

snapshot: introduce an intermediate `_refinedgroups` generator

This method will be used to improve the search for a good snapshot base. To
keep things simpler, we introduce the necessary function before doing any
delta base logic change. The next handful of commits will focus on refactoring
the code to let that new logic land as clearly as possible.

# General Idea

Right now, the search for a good delta base stop whenever we found a good one.
However, when using sparse-revlog, we should probably try a bit harder.

We do significant effort to increase delta re-use by jumping on "unrelated"
delta chains that provide better results. Moving to another chain for a better
result is good, but we have no guarantee we jump at a reasonable point in that
new chain. When we consider over the chains related to the parents, we start
from the higher-level snapshots. This is a way to consider the snapshot closer
to the current revision that has the best chance to produce a small delta. We
do benefit from this walk order when jumping to a better "unrelated" stack.

To counter-balance this, we'll introduce a way to "refine" the result. After a
good delta have been found, we'll keep searching for a better delta, using the
current best one as a starting point.

# Target Setup

The `finddeltainfo` method is responsible for the general search for a good
delta. It requests candidates base from `_candidategroups` and decides which
one are usable.

The `_candidategroups` generator act as a top-level filter, it does not care
about how we pick candidates, it just does basic filtering, excluding
revisions that have been tested already or that are an obvious misfit.

The `_rawgroups` generator is the one with the actual ancestors walking logic,
It does not care about what would do a good delta and what was already tested,
it just issues the initial candidates.

We introduce a new `_refinedgroup` function to bridge the gap between
`_candidategroups` and `_rawgroups`. It delegates the initial iteration logic
and then performing relevant refining of the valid base once found. (This
logic is yet to be added to function)

All these logics are fairly independent and easier to understand when standing
alone, not mixed with each other. It also makes it easy to test and try
different approaches for one of those four layers without affecting the other
ones.

# Technical details

To communicate `finddeltainfo` choice of "current best delta base" to the
`_refinegroup` logic, we plan to use python co-routine feature. The
`_candidategroups` and `_refinegroup` generators will become co-routine. This
will allow `_refinegroup` to detect when a good delta have been found and
triggers various refining steps.

For now, `_candidategroups` will just pass the value down the stack.

After poking at various option, the co-routine appears the best to keep each
layers focus on its duty, without the need to spread implementation details
across layers.

# coding=utf-8
from __future__ import absolute_import, print_function

import doctest
import os

def check(a, b):
    if a != b:
        print((a, b))

def cert(cn):
    return {'subject': ((('commonName', cn),),)}

from mercurial import (
    sslutil,
)

_verifycert = sslutil._verifycert
# Test non-wildcard certificates
check(_verifycert(cert('example.com'), 'example.com'),
      None)
check(_verifycert(cert('example.com'), 'www.example.com'),
      b'certificate is for example.com')
check(_verifycert(cert('www.example.com'), 'example.com'),
      b'certificate is for www.example.com')

# Test wildcard certificates
check(_verifycert(cert('*.example.com'), 'www.example.com'),
      None)
check(_verifycert(cert('*.example.com'), 'example.com'),
      b'certificate is for *.example.com')
check(_verifycert(cert('*.example.com'), 'w.w.example.com'),
      b'certificate is for *.example.com')

# Test subjectAltName
san_cert = {'subject': ((('commonName', 'example.com'),),),
            'subjectAltName': (('DNS', '*.example.net'),
                               ('DNS', 'example.net'))}
check(_verifycert(san_cert, 'example.net'),
      None)
check(_verifycert(san_cert, 'foo.example.net'),
      None)
# no fallback to subject commonName when subjectAltName has DNS
check(_verifycert(san_cert, 'example.com'),
      b'certificate is for *.example.net, example.net')
# fallback to subject commonName when no DNS in subjectAltName
san_cert = {'subject': ((('commonName', 'example.com'),),),
            'subjectAltName': (('IP Address', '8.8.8.8'),)}
check(_verifycert(san_cert, 'example.com'), None)

# Avoid some pitfalls
check(_verifycert(cert('*.foo'), 'foo'),
      b'certificate is for *.foo')
check(_verifycert(cert('*o'), 'foo'), None)

check(_verifycert({'subject': ()},
                  'example.com'),
      b'no commonName or subjectAltName found in certificate')
check(_verifycert(None, 'example.com'),
      b'no certificate received')

# Unicode (IDN) certname isn't supported
check(_verifycert(cert(u'\u4f8b.jp'), 'example.jp'),
      b'IDN in certificate not supported')

# The following tests are from CPython's test_ssl.py.
check(_verifycert(cert('example.com'), 'example.com'), None)
check(_verifycert(cert('example.com'), 'ExAmple.cOm'), None)
check(_verifycert(cert('example.com'), 'www.example.com'),
      b'certificate is for example.com')
check(_verifycert(cert('example.com'), '.example.com'),
      b'certificate is for example.com')
check(_verifycert(cert('example.com'), 'example.org'),
      b'certificate is for example.com')
check(_verifycert(cert('example.com'), 'exampleXcom'),
      b'certificate is for example.com')
check(_verifycert(cert('*.a.com'), 'foo.a.com'), None)
check(_verifycert(cert('*.a.com'), 'bar.foo.a.com'),
      b'certificate is for *.a.com')
check(_verifycert(cert('*.a.com'), 'a.com'),
      b'certificate is for *.a.com')
check(_verifycert(cert('*.a.com'), 'Xa.com'),
      b'certificate is for *.a.com')
check(_verifycert(cert('*.a.com'), '.a.com'),
      b'certificate is for *.a.com')

# only match one left-most wildcard
check(_verifycert(cert('f*.com'), 'foo.com'), None)
check(_verifycert(cert('f*.com'), 'f.com'), None)
check(_verifycert(cert('f*.com'), 'bar.com'),
      b'certificate is for f*.com')
check(_verifycert(cert('f*.com'), 'foo.a.com'),
      b'certificate is for f*.com')
check(_verifycert(cert('f*.com'), 'bar.foo.com'),
      b'certificate is for f*.com')

# NULL bytes are bad, CVE-2013-4073
check(_verifycert(cert('null.python.org\x00example.org'),
                  'null.python.org\x00example.org'), None)
check(_verifycert(cert('null.python.org\x00example.org'),
                  'example.org'),
      b'certificate is for null.python.org\x00example.org')
check(_verifycert(cert('null.python.org\x00example.org'),
                  'null.python.org'),
      b'certificate is for null.python.org\x00example.org')

# error cases with wildcards
check(_verifycert(cert('*.*.a.com'), 'bar.foo.a.com'),
      b'certificate is for *.*.a.com')
check(_verifycert(cert('*.*.a.com'), 'a.com'),
      b'certificate is for *.*.a.com')
check(_verifycert(cert('*.*.a.com'), 'Xa.com'),
      b'certificate is for *.*.a.com')
check(_verifycert(cert('*.*.a.com'), '.a.com'),
      b'certificate is for *.*.a.com')

check(_verifycert(cert('a.*.com'), 'a.foo.com'),
      b'certificate is for a.*.com')
check(_verifycert(cert('a.*.com'), 'a..com'),
      b'certificate is for a.*.com')
check(_verifycert(cert('a.*.com'), 'a.com'),
      b'certificate is for a.*.com')

# wildcard doesn't match IDNA prefix 'xn--'
idna = u'püthon.python.org'.encode('idna').decode('ascii')
check(_verifycert(cert(idna), idna), None)
check(_verifycert(cert('x*.python.org'), idna),
      b'certificate is for x*.python.org')
check(_verifycert(cert('xn--p*.python.org'), idna),
      b'certificate is for xn--p*.python.org')

# wildcard in first fragment and  IDNA A-labels in sequent fragments
# are supported.
idna = u'www*.pythön.org'.encode('idna').decode('ascii')
check(_verifycert(cert(idna),
                  u'www.pythön.org'.encode('idna').decode('ascii')),
      None)
check(_verifycert(cert(idna),
                  u'www1.pythön.org'.encode('idna').decode('ascii')),
      None)
check(_verifycert(cert(idna),
                  u'ftp.pythön.org'.encode('idna').decode('ascii')),
      b'certificate is for www*.xn--pythn-mua.org')
check(_verifycert(cert(idna),
                  u'pythön.org'.encode('idna').decode('ascii')),
      b'certificate is for www*.xn--pythn-mua.org')

c = {
    'notAfter': 'Jun 26 21:41:46 2011 GMT',
    'subject': (((u'commonName', u'linuxfrz.org'),),),
    'subjectAltName': (
        ('DNS', 'linuxfr.org'),
        ('DNS', 'linuxfr.com'),
        ('othername', '<unsupported>'),
    )
}
check(_verifycert(c, 'linuxfr.org'), None)
check(_verifycert(c, 'linuxfr.com'), None)
# Not a "DNS" entry
check(_verifycert(c, '<unsupported>'),
      b'certificate is for linuxfr.org, linuxfr.com')
# When there is a subjectAltName, commonName isn't used
check(_verifycert(c, 'linuxfrz.org'),
      b'certificate is for linuxfr.org, linuxfr.com')

# A pristine real-world example
c = {
    'notAfter': 'Dec 18 23:59:59 2011 GMT',
    'subject': (
        ((u'countryName', u'US'),),
        ((u'stateOrProvinceName', u'California'),),
        ((u'localityName', u'Mountain View'),),
        ((u'organizationName', u'Google Inc'),),
        ((u'commonName', u'mail.google.com'),),
    ),
}
check(_verifycert(c, 'mail.google.com'), None)
check(_verifycert(c, 'gmail.com'), b'certificate is for mail.google.com')

# Only commonName is considered
check(_verifycert(c, 'California'), b'certificate is for mail.google.com')

# Neither commonName nor subjectAltName
c = {
    'notAfter': 'Dec 18 23:59:59 2011 GMT',
    'subject': (
        ((u'countryName', u'US'),),
        ((u'stateOrProvinceName', u'California'),),
        ((u'localityName', u'Mountain View'),),
        ((u'organizationName', u'Google Inc'),),
    ),
}
check(_verifycert(c, 'mail.google.com'),
      b'no commonName or subjectAltName found in certificate')

# No DNS entry in subjectAltName but a commonName
c = {
    'notAfter': 'Dec 18 23:59:59 2099 GMT',
    'subject': (
        ((u'countryName', u'US'),),
        ((u'stateOrProvinceName', u'California'),),
        ((u'localityName', u'Mountain View'),),
        ((u'commonName', u'mail.google.com'),),
    ),
    'subjectAltName': (('othername', 'blabla'),),
}
check(_verifycert(c, 'mail.google.com'), None)

# No DNS entry subjectAltName and no commonName
c = {
    'notAfter': 'Dec 18 23:59:59 2099 GMT',
    'subject': (
        ((u'countryName', u'US'),),
        ((u'stateOrProvinceName', u'California'),),
        ((u'localityName', u'Mountain View'),),
        ((u'organizationName', u'Google Inc'),),
    ),
    'subjectAltName': (('othername', 'blabla'),),
}
check(_verifycert(c, 'google.com'),
      b'no commonName or subjectAltName found in certificate')

# Empty cert / no cert
check(_verifycert(None, 'example.com'), b'no certificate received')
check(_verifycert({}, 'example.com'), b'no certificate received')

# avoid denials of service by refusing more than one
# wildcard per fragment.
check(_verifycert({'subject': (((u'commonName', u'a*b.com'),),)},
                  'axxb.com'), None)
check(_verifycert({'subject': (((u'commonName', u'a*b.co*'),),)},
                  'axxb.com'), b'certificate is for a*b.co*')
check(_verifycert({'subject': (((u'commonName', u'a*b*.com'),),)},
                  'axxbxxc.com'),
      b'too many wildcards in certificate DNS name: a*b*.com')

def test_url():
    """
    >>> from mercurial import error, pycompat
    >>> from mercurial.util import url
    >>> from mercurial.utils.stringutil import forcebytestr

    This tests for edge cases in url.URL's parsing algorithm. Most of
    these aren't useful for documentation purposes, so they aren't
    part of the class's doc tests.

    Query strings and fragments:

    >>> url(b'http://host/a?b#c')
    <url scheme: 'http', host: 'host', path: 'a', query: 'b', fragment: 'c'>
    >>> url(b'http://host/a?')
    <url scheme: 'http', host: 'host', path: 'a'>
    >>> url(b'http://host/a#b#c')
    <url scheme: 'http', host: 'host', path: 'a', fragment: 'b#c'>
    >>> url(b'http://host/a#b?c')
    <url scheme: 'http', host: 'host', path: 'a', fragment: 'b?c'>
    >>> url(b'http://host/?a#b')
    <url scheme: 'http', host: 'host', path: '', query: 'a', fragment: 'b'>
    >>> url(b'http://host/?a#b', parsequery=False)
    <url scheme: 'http', host: 'host', path: '?a', fragment: 'b'>
    >>> url(b'http://host/?a#b', parsefragment=False)
    <url scheme: 'http', host: 'host', path: '', query: 'a#b'>
    >>> url(b'http://host/?a#b', parsequery=False, parsefragment=False)
    <url scheme: 'http', host: 'host', path: '?a#b'>

    IPv6 addresses:

    >>> url(b'ldap://[2001:db8::7]/c=GB?objectClass?one')
    <url scheme: 'ldap', host: '[2001:db8::7]', path: 'c=GB',
         query: 'objectClass?one'>
    >>> url(b'ldap://joe:xxx@[2001:db8::7]:80/c=GB?objectClass?one')
    <url scheme: 'ldap', user: 'joe', passwd: 'xxx', host: '[2001:db8::7]',
         port: '80', path: 'c=GB', query: 'objectClass?one'>

    Missing scheme, host, etc.:

    >>> url(b'://192.0.2.16:80/')
    <url path: '://192.0.2.16:80/'>
    >>> url(b'https://mercurial-scm.org')
    <url scheme: 'https', host: 'mercurial-scm.org'>
    >>> url(b'/foo')
    <url path: '/foo'>
    >>> url(b'bundle:/foo')
    <url scheme: 'bundle', path: '/foo'>
    >>> url(b'a?b#c')
    <url path: 'a?b', fragment: 'c'>
    >>> url(b'http://x.com?arg=/foo')
    <url scheme: 'http', host: 'x.com', query: 'arg=/foo'>
    >>> url(b'http://joe:xxx@/foo')
    <url scheme: 'http', user: 'joe', passwd: 'xxx', path: 'foo'>

    Just a scheme and a path:

    >>> url(b'mailto:[e-mail]')
    <url scheme: 'mailto', path: '[e-mail]'>
    >>> url(b'a:b:c:d')
    <url path: 'a:b:c:d'>
    >>> url(b'aa:bb:cc:dd')
    <url scheme: 'aa', path: 'bb:cc:dd'>

    SSH examples:

    >>> url(b'ssh://joe@host//home/joe')
    <url scheme: 'ssh', user: 'joe', host: 'host', path: '/home/joe'>
    >>> url(b'ssh://joe:xxx@host/src')
    <url scheme: 'ssh', user: 'joe', passwd: 'xxx', host: 'host', path: 'src'>
    >>> url(b'ssh://joe:xxx@host')
    <url scheme: 'ssh', user: 'joe', passwd: 'xxx', host: 'host'>
    >>> url(b'ssh://joe@host')
    <url scheme: 'ssh', user: 'joe', host: 'host'>
    >>> url(b'ssh://host')
    <url scheme: 'ssh', host: 'host'>
    >>> url(b'ssh://')
    <url scheme: 'ssh'>
    >>> url(b'ssh:')
    <url scheme: 'ssh'>

    Non-numeric port:

    >>> url(b'http://example.com:dd')
    <url scheme: 'http', host: 'example.com', port: 'dd'>
    >>> url(b'ssh://joe:xxx@host:ssh/foo')
    <url scheme: 'ssh', user: 'joe', passwd: 'xxx', host: 'host', port: 'ssh',
         path: 'foo'>

    Bad authentication credentials:

    >>> url(b'http://joe@joeville:123@4:@host/a?b#c')
    <url scheme: 'http', user: 'joe@joeville', passwd: '123@4:',
         host: 'host', path: 'a', query: 'b', fragment: 'c'>
    >>> url(b'http://!*#?/@!*#?/:@host/a?b#c')
    <url scheme: 'http', host: '!*', fragment: '?/@!*#?/:@host/a?b#c'>
    >>> url(b'http://!*#?@!*#?:@host/a?b#c')
    <url scheme: 'http', host: '!*', fragment: '?@!*#?:@host/a?b#c'>
    >>> url(b'http://!*@:!*@@host/a?b#c')
    <url scheme: 'http', user: '!*@', passwd: '!*@', host: 'host',
         path: 'a', query: 'b', fragment: 'c'>

    File paths:

    >>> url(b'a/b/c/d.g.f')
    <url path: 'a/b/c/d.g.f'>
    >>> url(b'/x///z/y/')
    <url path: '/x///z/y/'>
    >>> url(b'/foo:bar')
    <url path: '/foo:bar'>
    >>> url(b'\\\\foo:bar')
    <url path: '\\\\foo:bar'>
    >>> url(b'./foo:bar')
    <url path: './foo:bar'>

    Non-localhost file URL:

    >>> try:
    ...   u = url(b'file://mercurial-scm.org/foo')
    ... except error.Abort as e:
    ...   forcebytestr(e)
    'file:// URLs can only refer to localhost'

    Empty URL:

    >>> u = url(b'')
    >>> u
    <url path: ''>
    >>> str(u)
    ''

    Empty path with query string:

    >>> str(url(b'http://foo/?bar'))
    'http://foo/?bar'

    Invalid path:

    >>> u = url(b'http://foo/bar')
    >>> u.path = b'bar'
    >>> str(u)
    'http://foo/bar'

    >>> u = url(b'file:/foo/bar/baz')
    >>> u
    <url scheme: 'file', path: '/foo/bar/baz'>
    >>> str(u)
    'file:///foo/bar/baz'
    >>> pycompat.bytestr(u.localpath())
    '/foo/bar/baz'

    >>> u = url(b'file:///foo/bar/baz')
    >>> u
    <url scheme: 'file', path: '/foo/bar/baz'>
    >>> str(u)
    'file:///foo/bar/baz'
    >>> pycompat.bytestr(u.localpath())
    '/foo/bar/baz'

    >>> u = url(b'file:///f:oo/bar/baz')
    >>> u
    <url scheme: 'file', path: 'f:oo/bar/baz'>
    >>> str(u)
    'file:///f:oo/bar/baz'
    >>> pycompat.bytestr(u.localpath())
    'f:oo/bar/baz'

    >>> u = url(b'file://localhost/f:oo/bar/baz')
    >>> u
    <url scheme: 'file', host: 'localhost', path: 'f:oo/bar/baz'>
    >>> str(u)
    'file://localhost/f:oo/bar/baz'
    >>> pycompat.bytestr(u.localpath())
    'f:oo/bar/baz'

    >>> u = url(b'file:foo/bar/baz')
    >>> u
    <url scheme: 'file', path: 'foo/bar/baz'>
    >>> str(u)
    'file:foo/bar/baz'
    >>> pycompat.bytestr(u.localpath())
    'foo/bar/baz'
    """

if 'TERM' in os.environ:
    del os.environ['TERM']

doctest.testmod(optionflags=doctest.NORMALIZE_WHITESPACE)