1 files changed, 158 insertions, 0 deletions
diff --git a/lib/rubygems/version.rb b/lib/rubygems/version.rb
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+++ b/lib/rubygems/version.rb
@@ -0,0 +1,158 @@
+#--
+# Copyright 2006 by Chad Fowler, Rich Kilmer, Jim Weirich and others.
+# All rights reserved.
+# See LICENSE.txt for permissions.
+#++
+
+require 'rubygems'
+
+##
+# The Version class processes string versions into comparable values
+class Gem::Version
+
+  include Comparable
+
+  attr_reader :ints
+
+  attr_reader :version
+
+  ##
+  # Checks if version string is valid format
+  #
+  # str:: [String] the version string
+  # return:: [Boolean] true if the string format is correct, otherwise false
+  #
+  def self.correct?(version)
+    case version
+    when Integer, /\A\s*(\d+(\.\d+)*)*\s*\z/ then true
+    else false
+    end
+  end
+
+  ##
+  # Factory method to create a Version object.  Input may be a Version or a
+  # String.  Intended to simplify client code.
+  #
+  #   ver1 = Version.create('1.3.17')   # -> (Version object)
+  #   ver2 = Version.create(ver1)       # -> (ver1)
+  #   ver3 = Version.create(nil)        # -> nil
+  #
+  def self.create(input)
+    if input.respond_to? :version then
+      input
+    elsif input.nil? then
+      nil
+    else
+      new input
+    end
+  end
+
+  ##
+  # Constructs a version from the supplied string
+  #
+  # version:: [String] The version string.  Format is digit.digit...
+  #
+  def initialize(version)
+    raise ArgumentError, "Malformed version number string #{version}" unless
+      self.class.correct?(version)
+
+    self.version = version
+  end
+
+  def inspect # :nodoc:
+    "#<#{self.class} #{@version.inspect}>"
+  end
+
+  # Dump only the raw version string, not the complete object
+  def marshal_dump
+    [@version]
+  end
+
+  # Load custom marshal format
+  def marshal_load(array)
+    self.version = array[0]
+  end
+
+  # Strip ignored trailing zeros.
+  def normalize
+    @ints = @version.to_s.scan(/\d+/).map { |s| s.to_i }
+
+    return if @ints.length == 1
+
+    @ints.pop while @ints.last == 0
+
+    @ints = [0] if @ints.empty?
+  end
+
+  ##
+  # Returns the text representation of the version
+  #
+  # return:: [String] version as string
+  #
+  def to_s
+    @version
+  end
+
+  ##
+  # Convert version to integer array
+  #
+  # return:: [Array] list of integers
+  #
+  def to_ints
+    normalize unless @ints
+    @ints
+  end
+
+  def to_yaml_properties
+    ['@version']
+  end
+
+  def version=(version)
+    @version = version.to_s.strip
+    normalize
+  end
+
+  def yaml_initialize(tag, values)
+    self.version = values['version']
+  end
+
+  ##
+  # Compares two versions
+  #
+  # other:: [Version or .ints] other version to compare to
+  # return:: [Fixnum] -1, 0, 1
+  #
+  def <=>(other)
+    return 1 unless other
+    @ints <=> other.ints
+  end
+
+  def hash
+    to_ints.inject { |hash_code, n| hash_code + n }
+  end
+
+  # Return a new version object where the next to the last revision
+  # number is one greater. (e.g.  5.3.1 => 5.4)
+  def bump
+    ints = @ints.dup
+    ints.pop if ints.size > 1
+    ints[-1] += 1
+    self.class.new(ints.join("."))
+  end
+
+  #:stopdoc:
+
+  require 'rubygems/requirement'
+
+  # Gem::Requirement's original definition is nested in Version.
+  # Although an inappropriate place, current gems specs reference the nested
+  # class name explicitly.  To remain compatible with old software loading
+  # gemspecs, we leave a copy of original definition in Version, but define an
+  # alias Gem::Requirement for use everywhere else.
+
+  Requirement = ::Gem::Requirement
+
+  # :startdoc:
+
+end
+