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author | Fred Drake <fdrake@acm.org> | 2005-03-20 22:17:02 (GMT) |
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committer | Fred Drake <fdrake@acm.org> | 2005-03-20 22:17:02 (GMT) |
commit | 54398d6afb680bde217cc9529b2cd88485bec3d8 (patch) | |
tree | 31d6f86abf2f4867ea5a39a886ecc4d6bd044f5c /Lib/distutils/versionpredicate.py | |
parent | b1c96fd83e706d795382e80052650b92d0f14fb3 (diff) | |
download | cpython-54398d6afb680bde217cc9529b2cd88485bec3d8.zip cpython-54398d6afb680bde217cc9529b2cd88485bec3d8.tar.gz cpython-54398d6afb680bde217cc9529b2cd88485bec3d8.tar.bz2 |
helper code, mostly from Andy Harrington, for PEP 314 completion
Diffstat (limited to 'Lib/distutils/versionpredicate.py')
-rw-r--r-- | Lib/distutils/versionpredicate.py | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/Lib/distutils/versionpredicate.py b/Lib/distutils/versionpredicate.py new file mode 100644 index 0000000..5126ebf --- /dev/null +++ b/Lib/distutils/versionpredicate.py @@ -0,0 +1,103 @@ +"""Module for parsing and testing package version predicate strings. +""" +import re +import version +import operator + +re_validPackage = re.compile(r"(?i)^\s*([a-z_]\w*(?:\.[a-z_]\w*)*)(.*)") +# (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: " + pred + comp, verStr = res.groups() + return (comp, 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)") + >>> print v + pyepat.abc (> 1.0, < 3333.3a1, != 1555.1b3) + >>> 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 + >>> v = VersionPredicate("pat( == 0.1 ) ") + >>> v.satisfied_by("0.1") + True + >>> v.satisfied_by("0.2") + False + >>> v = VersionPredicate("p1.p2.p3.p4(>=1.0, <=1.3a1, !=1.2zb3)") + Traceback (most recent call last): + ... + ValueError: invalid version number '1.2zb3' + + """ + + 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 " + versionPredicateStr + self.name, paren = match.groups() + paren = paren.strip() + if paren: + match = re_paren.match(paren) + if not match: + raise ValueError, "Expected parenthesized list: " + 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 + + +def check_provision(value): + m = re.match("[a-zA-Z_]\w*(\.[a-zA-Z_]\w*)*(\s*\([^)]+\))?$", value) + if not m: + raise ValueError("illegal provides specification: %r" % value) |