347 lines
		
	
	
	
		
			12 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			347 lines
		
	
	
	
		
			12 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| #
 | |
| # distutils/version.py
 | |
| #
 | |
| # Implements multiple version numbering conventions for the
 | |
| # Python Module Distribution Utilities.
 | |
| #
 | |
| # $Id$
 | |
| #
 | |
| 
 | |
| """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 re
 | |
| 
 | |
| 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; and route
 | |
|     rich comparisons to _cmp.
 | |
|     """
 | |
| 
 | |
|     def __init__ (self, vstring=None):
 | |
|         if vstring:
 | |
|             self.parse(vstring)
 | |
| 
 | |
|     def __repr__ (self):
 | |
|         return "%s ('%s')" % (self.__class__.__name__, str(self))
 | |
| 
 | |
|     def __eq__(self, other):
 | |
|         c = self._cmp(other)
 | |
|         if c is NotImplemented:
 | |
|             return c
 | |
|         return c == 0
 | |
| 
 | |
|     def __lt__(self, other):
 | |
|         c = self._cmp(other)
 | |
|         if c is NotImplemented:
 | |
|             return c
 | |
|         return c < 0
 | |
| 
 | |
|     def __le__(self, other):
 | |
|         c = self._cmp(other)
 | |
|         if c is NotImplemented:
 | |
|             return c
 | |
|         return c <= 0
 | |
| 
 | |
|     def __gt__(self, other):
 | |
|         c = self._cmp(other)
 | |
|         if c is NotImplemented:
 | |
|             return c
 | |
|         return c > 0
 | |
| 
 | |
|     def __ge__(self, other):
 | |
|         c = self._cmp(other)
 | |
|         if c is NotImplemented:
 | |
|             return c
 | |
|         return c >= 0
 | |
| 
 | |
| 
 | |
| # 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 | re.ASCII)
 | |
| 
 | |
| 
 | |
|     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(int, [major, minor, patch]))
 | |
|         else:
 | |
|             self.version = tuple(map(int, [major, minor])) + (0,)
 | |
| 
 | |
|         if prerelease:
 | |
|             self.prerelease = (prerelease[0], int(prerelease_num))
 | |
|         else:
 | |
|             self.prerelease = None
 | |
| 
 | |
| 
 | |
|     def __str__ (self):
 | |
| 
 | |
|         if self.version[2] == 0:
 | |
|             vstring = '.'.join(map(str, self.version[0:2]))
 | |
|         else:
 | |
|             vstring = '.'.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, str):
 | |
|             other = StrictVersion(other)
 | |
|         elif not isinstance(other, StrictVersion):
 | |
|             return NotImplemented
 | |
| 
 | |
|         if self.version != other.version:
 | |
|             # numeric versions don't match
 | |
|             # prerelease stuff doesn't matter
 | |
|             if self.version < other.version:
 | |
|                 return -1
 | |
|             else:
 | |
|                 return 1
 | |
| 
 | |
|         # 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):
 | |
|             if self.prerelease == other.prerelease:
 | |
|                 return 0
 | |
|             elif self.prerelease < other.prerelease:
 | |
|                 return -1
 | |
|             else:
 | |
|                 return 1
 | |
|         else:
 | |
|             assert False, "never get here"
 | |
| 
 | |
| # end class StrictVersion
 | |
| 
 | |
| 
 | |
| # The rules according to Greg Stein:
 | |
| # 1) a version number has 1 or more numbers separated 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 accommodate 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 = [x for x in self.component_re.split(vstring)
 | |
|                               if x and x != '.']
 | |
|         for i, obj in enumerate(components):
 | |
|             try:
 | |
|                 components[i] = int(obj)
 | |
|             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, str):
 | |
|             other = LooseVersion(other)
 | |
|         elif not isinstance(other, LooseVersion):
 | |
|             return NotImplemented
 | |
| 
 | |
|         if self.version == other.version:
 | |
|             return 0
 | |
|         if self.version < other.version:
 | |
|             return -1
 | |
|         if self.version > other.version:
 | |
|             return 1
 | |
| 
 | |
| 
 | |
| # end class LooseVersion
 |