xref: /titanic_50/usr/src/tools/onbld/Scm/Version.py (revision 6c1891ea28c10049521d8647a32ef85d9449a8cb)
1#
2#  This program is free software; you can redistribute it and/or modify
3#  it under the terms of the GNU General Public License version 2
4#  as published by the Free Software Foundation.
5#
6#  This program is distributed in the hope that it will be useful,
7#  but WITHOUT ANY WARRANTY; without even the implied warranty of
8#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
9#  GNU General Public License for more details.
10#
11#  You should have received a copy of the GNU General Public License
12#  along with this program; if not, write to the Free Software
13#  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
14#
15
16#
17# Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
18# Use is subject to license terms.
19#
20# Copyright 2008, 2010, Richard Lowe
21#
22
23'''
24Deal with Mercurial versioning.
25
26At a basic level, code to verify that the version of Mercurial in use
27is suitable for use with Cadmium, and compare that version for the
28sake of adapting to Mercurial API changes.
29'''
30
31#
32# It is important that this module rely on as little of Mercurial as
33# is possible.
34#
35
36#
37# Mercurial >= 1.2 has util.version(), prior versions
38# version.get_version() We discover which to use this way, rather than
39# via ImportError to account for mercurial.demandimport delaying the
40# ImportError exception.
41#
42# This code needs to remain, even though versions prior to 1.2 aren't
43# supported, to allow us to produce the error message which states that they
44# are not supported.
45#
46from mercurial import util
47if hasattr(util, 'version'):
48    hg_version = util.version
49else:
50    from mercurial import version
51    hg_version = version.get_version
52
53
54class VersionMismatch(Exception):
55    "Exception used to indicate a mismatch between SCM tools and Mercurial"
56    pass
57
58#
59# List of versions that are explicitly acceptable to us
60#
61GOOD_VERSIONS = ['1.3.1', '1.4.2', '1.5.4', '1.6.2', '1.6.3']
62
63
64def check_version():
65    '''Check that we're running on a suitable version of Mercurial'''
66
67    def versionstring(versions):
68        '''return the list, versions, as a vaguely grammatical string'''
69        if len(versions) > 1:
70            return "%s or %s" % (', '.join(versions[0:-1]), versions[-1])
71        else:
72            return versions[0]
73
74    if hg_version() not in GOOD_VERSIONS:
75        raise VersionMismatch("Scm expects Mercurial version %s, "
76                              "actual version is %s." %
77                              (versionstring(GOOD_VERSIONS),
78                               hg_version()))
79
80
81def _split_version(ver):
82    '''Return the Mercurial version as a list [MAJOR, MINOR, MICRO],
83    if this is not a released Mercurial return None.'''
84
85    try:
86        l = map(int, ver.split('.'))
87        # If there's only one element, it's not really a tagged version
88        if len(l) <= 1:
89            return None
90        else:
91            return l
92    except ValueError:
93        return None
94
95
96def at_least(desired):
97    '''Return boolean indicating if the running version is greater
98    than or equal to, the version specified by major, minor, micro'''
99
100    hgver = _split_version(hg_version())
101    desired = map(int, desired.split('.'))
102
103    #
104    # If _split_version() returns None, we're running on a Mercurial that
105    # has not been tagged as a release.  We assume this to be newer
106    # than any released version.
107    #
108    if hgver == None:
109        return True
110
111    # Pad our versions to the same overall length, appending 0's
112    while len(hgver) < len(desired):
113        hgver.append(0)
114    while len(desired) < len(hgver):
115        desired.append(0)
116
117    for real, req in zip(hgver, desired):
118        if real != req:
119            return real > req
120
121    return True
122