summaryrefslogtreecommitdiff
path: root/Lib/distutils/versionpredicate.py
blob: b0dd9f45bff675672d3c8da275bf1da9bb1057fe (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
"""Module for parsing and testing package version predicate strings.
"""
import re
import distutils.version
import operator


re_validPackage = re.compile(r"(?i)^\s*([a-z_]\w*(?:\.[a-z_]\w*)*)(.*)",
    re.ASCII)
# (package) (rest)

re_paren = re.compile(r"^\s*\((.*)\)\s*$") # (list) inside of parentheses
re_splitComparison = re.compile(r"^\s*(<=|>=|<|>|!=|==)\s*([^\s,]+)\s*$")
# (comp) (version)


def splitUp(pred):
    """Parse a single version comparison.

    Return (comparison string, StrictVersion)
    """
    res = re_splitComparison.match(pred)
    if not res:
        raise ValueError("bad package restriction syntax: %r" % pred)
    comp, verStr = res.groups()
    return (comp, distutils.version.StrictVersion(verStr))

compmap = {"<": operator.lt, "<=": operator.le, "==": operator.eq,
           ">": operator.gt, ">=": operator.ge, "!=": operator.ne}

class VersionPredicate:
    """Parse and test package version predicates.

    >>> v = VersionPredicate('pyepat.abc (>1.0, <3333.3a1, !=1555.1b3)')

    The `name` attribute provides the full dotted name that is given::

    >>> v.name
    'pyepat.abc'

    The str() of a `VersionPredicate` provides a normalized
    human-readable version of the expression::

    >>> print(v)
    pyepat.abc (> 1.0, < 3333.3a1, != 1555.1b3)

    The `satisfied_by()` method can be used to determine with a given
    version number is included in the set described by the version
    restrictions::

    >>> v.satisfied_by('1.1')
    True
    >>> v.satisfied_by('1.4')
    True
    >>> v.satisfied_by('1.0')
    False
    >>> v.satisfied_by('4444.4')
    False
    >>> v.satisfied_by('1555.1b3')
    False

    `VersionPredicate` is flexible in accepting extra whitespace::

    >>> v = VersionPredicate(' pat( ==  0.1  )  ')
    >>> v.name
    'pat'
    >>> v.satisfied_by('0.1')
    True
    >>> v.satisfied_by('0.2')
    False

    If any version numbers passed in do not conform to the
    restrictions of `StrictVersion`, a `ValueError` is raised::

    >>> v = VersionPredicate('p1.p2.p3.p4(>=1.0, <=1.3a1, !=1.2zb3)')
    Traceback (most recent call last):
      ...
    ValueError: invalid version number '1.2zb3'

    It the module or package name given does not conform to what's
    allowed as a legal module or package name, `ValueError` is
    raised::

    >>> v = VersionPredicate('foo-bar')
    Traceback (most recent call last):
      ...
    ValueError: expected parenthesized list: '-bar'

    >>> v = VersionPredicate('foo bar (12.21)')
    Traceback (most recent call last):
      ...
    ValueError: expected parenthesized list: 'bar (12.21)'

    """

    def __init__(self, versionPredicateStr):
        """Parse a version predicate string.
        """
        # Fields:
        #    name:  package name
        #    pred:  list of (comparison string, StrictVersion)

        versionPredicateStr = versionPredicateStr.strip()
        if not versionPredicateStr:
            raise ValueError("empty package restriction")
        match = re_validPackage.match(versionPredicateStr)
        if not match:
            raise ValueError("bad package name in %r" % versionPredicateStr)
        self.name, paren = match.groups()
        paren = paren.strip()
        if paren:
            match = re_paren.match(paren)
            if not match:
                raise ValueError("expected parenthesized list: %r" % paren)
            str = match.groups()[0]
            self.pred = [splitUp(aPred) for aPred in str.split(",")]
            if not self.pred:
                raise ValueError("empty parenthesized list in %r"
                                 % versionPredicateStr)
        else:
            self.pred = []

    def __str__(self):
        if self.pred:
            seq = [cond + " " + str(ver) for cond, ver in self.pred]
            return self.name + " (" + ", ".join(seq) + ")"
        else:
            return self.name

    def satisfied_by(self, version):
        """True if version is compatible with all the predicates in self.
        The parameter version must be acceptable to the StrictVersion
        constructor.  It may be either a string or StrictVersion.
        """
        for cond, ver in self.pred:
            if not compmap[cond](version, ver):
                return False
        return True


_provision_rx = None

def split_provision(value):
    """Return the name and optional version number of a provision.

    The version number, if given, will be returned as a `StrictVersion`
    instance, otherwise it will be `None`.

    >>> split_provision('mypkg')
    ('mypkg', None)
    >>> split_provision(' mypkg( 1.2 ) ')
    ('mypkg', StrictVersion ('1.2'))
    """
    global _provision_rx
    if _provision_rx is None:
        _provision_rx = re.compile(
            "([a-zA-Z_]\w*(?:\.[a-zA-Z_]\w*)*)(?:\s*\(\s*([^)\s]+)\s*\))?$",
            re.ASCII)
    value = value.strip()
    m = _provision_rx.match(value)
    if not m:
        raise ValueError("illegal provides specification: %r" % value)
    ver = m.group(2) or None
    if ver:
        ver = distutils.version.StrictVersion(ver)
    return m.group(1), ver