Tor Norbye | 3a2425a5 | 2013-11-04 10:16:08 -0800 | [diff] [blame] | 1 | """Module for parsing and testing package version predicate strings. |
| 2 | """ |
| 3 | import re |
| 4 | import distutils.version |
| 5 | import operator |
| 6 | |
| 7 | |
| 8 | re_validPackage = re.compile(r"(?i)^\s*([a-z_]\w*(?:\.[a-z_]\w*)*)(.*)") |
| 9 | # (package) (rest) |
| 10 | |
| 11 | re_paren = re.compile(r"^\s*\((.*)\)\s*$") # (list) inside of parentheses |
| 12 | re_splitComparison = re.compile(r"^\s*(<=|>=|<|>|!=|==)\s*([^\s,]+)\s*$") |
| 13 | # (comp) (version) |
| 14 | |
| 15 | |
| 16 | def splitUp(pred): |
| 17 | """Parse a single version comparison. |
| 18 | |
| 19 | Return (comparison string, StrictVersion) |
| 20 | """ |
| 21 | res = re_splitComparison.match(pred) |
| 22 | if not res: |
| 23 | raise ValueError("bad package restriction syntax: %r" % pred) |
| 24 | comp, verStr = res.groups() |
| 25 | return (comp, distutils.version.StrictVersion(verStr)) |
| 26 | |
| 27 | compmap = {"<": operator.lt, "<=": operator.le, "==": operator.eq, |
| 28 | ">": operator.gt, ">=": operator.ge, "!=": operator.ne} |
| 29 | |
| 30 | class VersionPredicate: |
| 31 | """Parse and test package version predicates. |
| 32 | |
| 33 | >>> v = VersionPredicate('pyepat.abc (>1.0, <3333.3a1, !=1555.1b3)') |
| 34 | |
| 35 | The `name` attribute provides the full dotted name that is given:: |
| 36 | |
| 37 | >>> v.name |
| 38 | 'pyepat.abc' |
| 39 | |
| 40 | The str() of a `VersionPredicate` provides a normalized |
| 41 | human-readable version of the expression:: |
| 42 | |
| 43 | >>> print v |
| 44 | pyepat.abc (> 1.0, < 3333.3a1, != 1555.1b3) |
| 45 | |
| 46 | The `satisfied_by()` method can be used to determine with a given |
| 47 | version number is included in the set described by the version |
| 48 | restrictions:: |
| 49 | |
| 50 | >>> v.satisfied_by('1.1') |
| 51 | True |
| 52 | >>> v.satisfied_by('1.4') |
| 53 | True |
| 54 | >>> v.satisfied_by('1.0') |
| 55 | False |
| 56 | >>> v.satisfied_by('4444.4') |
| 57 | False |
| 58 | >>> v.satisfied_by('1555.1b3') |
| 59 | False |
| 60 | |
| 61 | `VersionPredicate` is flexible in accepting extra whitespace:: |
| 62 | |
| 63 | >>> v = VersionPredicate(' pat( == 0.1 ) ') |
| 64 | >>> v.name |
| 65 | 'pat' |
| 66 | >>> v.satisfied_by('0.1') |
| 67 | True |
| 68 | >>> v.satisfied_by('0.2') |
| 69 | False |
| 70 | |
| 71 | If any version numbers passed in do not conform to the |
| 72 | restrictions of `StrictVersion`, a `ValueError` is raised:: |
| 73 | |
| 74 | >>> v = VersionPredicate('p1.p2.p3.p4(>=1.0, <=1.3a1, !=1.2zb3)') |
| 75 | Traceback (most recent call last): |
| 76 | ... |
| 77 | ValueError: invalid version number '1.2zb3' |
| 78 | |
| 79 | It the module or package name given does not conform to what's |
| 80 | allowed as a legal module or package name, `ValueError` is |
| 81 | raised:: |
| 82 | |
| 83 | >>> v = VersionPredicate('foo-bar') |
| 84 | Traceback (most recent call last): |
| 85 | ... |
| 86 | ValueError: expected parenthesized list: '-bar' |
| 87 | |
| 88 | >>> v = VersionPredicate('foo bar (12.21)') |
| 89 | Traceback (most recent call last): |
| 90 | ... |
| 91 | ValueError: expected parenthesized list: 'bar (12.21)' |
| 92 | |
| 93 | """ |
| 94 | |
| 95 | def __init__(self, versionPredicateStr): |
| 96 | """Parse a version predicate string. |
| 97 | """ |
| 98 | # Fields: |
| 99 | # name: package name |
| 100 | # pred: list of (comparison string, StrictVersion) |
| 101 | |
| 102 | versionPredicateStr = versionPredicateStr.strip() |
| 103 | if not versionPredicateStr: |
| 104 | raise ValueError("empty package restriction") |
| 105 | match = re_validPackage.match(versionPredicateStr) |
| 106 | if not match: |
| 107 | raise ValueError("bad package name in %r" % versionPredicateStr) |
| 108 | self.name, paren = match.groups() |
| 109 | paren = paren.strip() |
| 110 | if paren: |
| 111 | match = re_paren.match(paren) |
| 112 | if not match: |
| 113 | raise ValueError("expected parenthesized list: %r" % paren) |
| 114 | str = match.groups()[0] |
| 115 | self.pred = [splitUp(aPred) for aPred in str.split(",")] |
| 116 | if not self.pred: |
| 117 | raise ValueError("empty parenthesized list in %r" |
| 118 | % versionPredicateStr) |
| 119 | else: |
| 120 | self.pred = [] |
| 121 | |
| 122 | def __str__(self): |
| 123 | if self.pred: |
| 124 | seq = [cond + " " + str(ver) for cond, ver in self.pred] |
| 125 | return self.name + " (" + ", ".join(seq) + ")" |
| 126 | else: |
| 127 | return self.name |
| 128 | |
| 129 | def satisfied_by(self, version): |
| 130 | """True if version is compatible with all the predicates in self. |
| 131 | The parameter version must be acceptable to the StrictVersion |
| 132 | constructor. It may be either a string or StrictVersion. |
| 133 | """ |
| 134 | for cond, ver in self.pred: |
| 135 | if not compmap[cond](version, ver): |
| 136 | return False |
| 137 | return True |
| 138 | |
| 139 | |
| 140 | _provision_rx = None |
| 141 | |
| 142 | def split_provision(value): |
| 143 | """Return the name and optional version number of a provision. |
| 144 | |
| 145 | The version number, if given, will be returned as a `StrictVersion` |
| 146 | instance, otherwise it will be `None`. |
| 147 | |
| 148 | >>> split_provision('mypkg') |
| 149 | ('mypkg', None) |
| 150 | >>> split_provision(' mypkg( 1.2 ) ') |
| 151 | ('mypkg', StrictVersion ('1.2')) |
| 152 | """ |
| 153 | global _provision_rx |
| 154 | if _provision_rx is None: |
| 155 | _provision_rx = re.compile( |
| 156 | "([a-zA-Z_]\w*(?:\.[a-zA-Z_]\w*)*)(?:\s*\(\s*([^)\s]+)\s*\))?$") |
| 157 | value = value.strip() |
| 158 | m = _provision_rx.match(value) |
| 159 | if not m: |
| 160 | raise ValueError("illegal provides specification: %r" % value) |
| 161 | ver = m.group(2) or None |
| 162 | if ver: |
| 163 | ver = distutils.version.StrictVersion(ver) |
| 164 | return m.group(1), ver |