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author | Greg Ward <gward@python.net> | 1998-12-18 22:00:30 (GMT) |
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committer | Greg Ward <gward@python.net> | 1998-12-18 22:00:30 (GMT) |
commit | ee789b960191a4eafa08dd044f5c74e98ea66950 (patch) | |
tree | ff2796b1f1703d785af26e0e1597b1a2a897cb30 /Lib | |
parent | b083a9fb540b002fe8e386dd4168deacfb0bf574 (diff) | |
download | cpython-ee789b960191a4eafa08dd044f5c74e98ea66950.zip cpython-ee789b960191a4eafa08dd044f5c74e98ea66950.tar.gz cpython-ee789b960191a4eafa08dd044f5c74e98ea66950.tar.bz2 |
Initial checkin of distutils source files.
Diffstat (limited to 'Lib')
-rw-r--r-- | Lib/distutils/__init__.py | 0 | ||||
-rw-r--r-- | Lib/distutils/version.py | 301 |
2 files changed, 301 insertions, 0 deletions
diff --git a/Lib/distutils/__init__.py b/Lib/distutils/__init__.py new file mode 100644 index 0000000..e69de29 --- /dev/null +++ b/Lib/distutils/__init__.py diff --git a/Lib/distutils/version.py b/Lib/distutils/version.py new file mode 100644 index 0000000..918a1de --- /dev/null +++ b/Lib/distutils/version.py @@ -0,0 +1,301 @@ +# +# distutils/version.py +# +# Implements multiple version numbering conventions for the +# Python Module Distribution Utilities. +# +# written by Greg Ward, 1998/12/17 +# +# $Id$ +# + +"""Provides classes to represent module version numbers (one class for +each style of version numbering). There are currently two such classes +implemented: StrictVersion and LooseVersion. + +Every version number class implements the following interface: + * the 'parse' method takes a string and parses it to some internal + representation; if the string is an invalid version number, + 'parse' raises a ValueError exception + * the class constructor takes an optional string argument which, + if supplied, is passed to 'parse' + * __str__ reconstructs the string that was passed to 'parse' (or + an equivalent string -- ie. one that will generate an equivalent + version number instance) + * __repr__ generates Python code to recreate the version number instance + * __cmp__ compares the current instance with either another instance + of the same class or a string (which will be parsed to an instance + of the same class, thus must follow the same rules) +""" + +import string, re +from types import StringType + +class Version: + """Abstract base class for version numbering classes. Just provides + constructor (__init__) and reproducer (__repr__), because those + seem to be the same for all version numbering classes. + """ + + def __init__ (self, vstring=None): + if vstring: + self.parse (vstring) + + def __repr__ (self): + return "%s ('%s')" % (self.__class__.__name__, str (self)) + + +# Interface for version-number classes -- must be implemented +# by the following classes (the concrete ones -- Version should +# be treated as an abstract class). +# __init__ (string) - create and take same action as 'parse' +# (string parameter is optional) +# parse (string) - convert a string representation to whatever +# internal representation is appropriate for +# this style of version numbering +# __str__ (self) - convert back to a string; should be very similar +# (if not identical to) the string supplied to parse +# __repr__ (self) - generate Python code to recreate +# the instance +# __cmp__ (self, other) - compare two version numbers ('other' may +# be an unparsed version string, or another +# instance of your version class) + + +class StrictVersion (Version): + + """Version numbering for anal retentives and software idealists. + Implements the standard interface for version number classes as + described above. A version number consists of two or three + dot-separated numeric components, with an optional "pre-release" tag + on the end. The pre-release tag consists of the letter 'a' or 'b' + followed by a number. If the numeric components of two version + numbers are equal, then one with a pre-release tag will always + be deemed earlier (lesser) than one without. + + The following are valid version numbers (shown in the order that + would be obtained by sorting according to the supplied cmp function): + + 0.4 0.4.0 (these two are equivalent) + 0.4.1 + 0.5a1 + 0.5b3 + 0.5 + 0.9.6 + 1.0 + 1.0.4a3 + 1.0.4b1 + 1.0.4 + + The following are examples of invalid version numbers: + + 1 + 2.7.2.2 + 1.3.a4 + 1.3pl1 + 1.3c4 + + The rationale for this version numbering system will be explained + in the distutils documentation. + """ + + version_re = re.compile (r'^(\d+) \. (\d+) (\. (\d+))? ([ab](\d+))?$', + re.VERBOSE) + + + def parse (self, vstring): + match = self.version_re.match (vstring) + if not match: + raise ValueError, "invalid version number '%s'" % vstring + + (major, minor, patch, prerelease, prerelease_num) = \ + match.group (1, 2, 4, 5, 6) + + if patch: + self.version = tuple (map (string.atoi, [major, minor, patch])) + else: + self.version = tuple (map (string.atoi, [major, minor]) + [0]) + + if prerelease: + self.prerelease = (prerelease[0], string.atoi (prerelease_num)) + else: + self.prerelease = None + + + def __str__ (self): + + if self.version[2] == 0: + vstring = string.join (map (str, self.version[0:2]), '.') + else: + vstring = string.join (map (str, self.version), '.') + + if self.prerelease: + vstring = vstring + self.prerelease[0] + str (self.prerelease[1]) + + return vstring + + + def __cmp__ (self, other): + if isinstance (other, StringType): + other = StrictVersion (other) + + compare = cmp (self.version, other.version) + if (compare == 0): # have to compare prerelease + + # case 1: neither has prerelease; they're equal + # case 2: self has prerelease, other doesn't; other is greater + # case 3: self doesn't have prerelease, other does: self is greater + # case 4: both have prerelease: must compare them! + + if (not self.prerelease and not other.prerelease): + return 0 + elif (self.prerelease and not other.prerelease): + return -1 + elif (not self.prerelease and other.prerelease): + return 1 + elif (self.prerelease and other.prerelease): + return cmp (self.prerelease, other.prerelease) + + else: # numeric versions don't match -- + return compare # prerelease stuff doesn't matter + + +# end class StrictVersion + + +# The rules according to Greg Stein: +# 1) a version number has 1 or more numbers separate by a period or by +# sequences of letters. If only periods, then these are compared +# left-to-right to determine an ordering. +# 2) sequences of letters are part of the tuple for comparison and are +# compared lexicographically +# 3) recognize the numeric components may have leading zeroes +# +# The LooseVersion class below implements these rules: a version number +# string is split up into a tuple of integer and string components, and +# comparison is a simple tuple comparison. This means that version +# numbers behave in a predictable and obvious way, but a way that might +# not necessarily be how people *want* version numbers to behave. There +# wouldn't be a problem if people could stick to purely numeric version +# numbers: just split on period and compare the numbers as tuples. +# However, people insist on putting letters into their version numbers; +# the most common purpose seems to be: +# - indicating a "pre-release" version +# ('alpha', 'beta', 'a', 'b', 'pre', 'p') +# - indicating a post-release patch ('p', 'pl', 'patch') +# but of course this can't cover all version number schemes, and there's +# no way to know what a programmer means without asking him. +# +# The problem is what to do with letters (and other non-numeric +# characters) in a version number. The current implementation does the +# obvious and predictable thing: keep them as strings and compare +# lexically within a tuple comparison. This has the desired effect if +# an appended letter sequence implies something "post-release": +# eg. "0.99" < "0.99pl14" < "1.0", and "5.001" < "5.001m" < "5.002". +# +# However, if letters in a version number imply a pre-release version, +# the "obvious" thing isn't correct. Eg. you would expect that +# "1.5.1" < "1.5.2a2" < "1.5.2", but under the tuple/lexical comparison +# implemented here, this just isn't so. +# +# Two possible solutions come to mind. The first is to tie the +# comparison algorithm to a particular set of semantic rules, as has +# been done in the StrictVersion class above. This works great as long +# as everyone can go along with bondage and discipline. Hopefully a +# (large) subset of Python module programmers will agree that the +# particular flavour of bondage and discipline provided by StrictVersion +# provides enough benefit to be worth using, and will submit their +# version numbering scheme to its domination. The free-thinking +# anarchists in the lot will never give in, though, and something needs +# to be done to accomodate them. +# +# Perhaps a "moderately strict" version class could be implemented that +# lets almost anything slide (syntactically), and makes some heuristic +# assumptions about non-digits in version number strings. This could +# sink into special-case-hell, though; if I was as talented and +# idiosyncratic as Larry Wall, I'd go ahead and implement a class that +# somehow knows that "1.2.1" < "1.2.2a2" < "1.2.2" < "1.2.2pl3", and is +# just as happy dealing with things like "2g6" and "1.13++". I don't +# think I'm smart enough to do it right though. +# +# In any case, I've coded the test suite for this module (see +# ../test/test_version.py) specifically to fail on things like comparing +# "1.2a2" and "1.2". That's not because the *code* is doing anything +# wrong, it's because the simple, obvious design doesn't match my +# complicated, hairy expectations for real-world version numbers. It +# would be a snap to fix the test suite to say, "Yep, LooseVersion does +# the Right Thing" (ie. the code matches the conception). But I'd rather +# have a conception that matches common notions about version numbers. + +class LooseVersion (Version): + + """Version numbering for anarchists and software realists. + Implements the standard interface for version number classes as + described above. A version number consists of a series of numbers, + separated by either periods or strings of letters. When comparing + version numbers, the numeric components will be compared + numerically, and the alphabetic components lexically. The following + are all valid version numbers, in no particular order: + + 1.5.1 + 1.5.2b2 + 161 + 3.10a + 8.02 + 3.4j + 1996.07.12 + 3.2.pl0 + 3.1.1.6 + 2g6 + 11g + 0.960923 + 2.2beta29 + 1.13++ + 5.5.kw + 2.0b1pl0 + + In fact, there is no such thing as an invalid version number under + this scheme; the rules for comparison are simple and predictable, + but may not always give the results you want (for some definition + of "want"). + """ + + component_re = re.compile(r'(\d+ | [a-z]+ | \.)', re.VERBOSE) + + def __init__ (self, vstring=None): + if vstring: + self.parse (vstring) + + + def parse (self, vstring): + # I've given up on thinking I can reconstruct the version string + # from the parsed tuple -- so I just store the string here for + # use by __str__ + self.vstring = vstring + components = filter (lambda x: x and x != '.', + self.component_re.split (vstring)) + for i in range (len (components)): + try: + components[i] = int (components[i]) + except ValueError: + pass + + self.version = components + + + def __str__ (self): + return self.vstring + + + def __repr__ (self): + return "LooseVersion ('%s')" % str (self) + + + def __cmp__ (self, other): + if isinstance (other, StringType): + other = LooseVersion (other) + + return cmp (self.version, other.version) + + +# end class LooseVersion |