* lib/rubygems*: Updated to RubyGems 2.0

* test/rubygems*:  ditto.

* common.mk (prelude):  Updated for RubyGems 2.0 source rearrangement.

* tool/change_maker.rb:  Allow invalid UTF-8 characters in source
  files.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37976 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/rubygems/core_ext/kernel_gem.rb

@@ -0,0 +1,53 @@
+module Kernel
+
+  # REFACTOR: This should be pulled out into some kind of hacks file.
+  remove_method :gem if 'method' == defined? gem # from gem_prelude.rb on 1.9
+
+  ##
+  # Use Kernel#gem to activate a specific version of +gem_name+.
+  #
+  # +requirements+ is a list of version requirements that the
+  # specified gem must match, most commonly "= example.version.number".  See
+  # Gem::Requirement for how to specify a version requirement.
+  #
+  # If you will be activating the latest version of a gem, there is no need to
+  # call Kernel#gem, Kernel#require will do the right thing for you.
+  #
+  # Kernel#gem returns true if the gem was activated, otherwise false.  If the
+  # gem could not be found, didn't match the version requirements, or a
+  # different version was already activated, an exception will be raised.
+  #
+  # Kernel#gem should be called *before* any require statements (otherwise
+  # RubyGems may load a conflicting library version).
+  #
+  # In older RubyGems versions, the environment variable GEM_SKIP could be
+  # used to skip activation of specified gems, for example to test out changes
+  # that haven't been installed yet.  Now RubyGems defers to -I and the
+  # RUBYLIB environment variable to skip activation of a gem.
+  #
+  # Example:
+  #
+  #   GEM_SKIP=libA:libB ruby -I../libA -I../libB ./mycode.rb
+
+  def gem(gem_name, *requirements) # :doc:
+    skip_list = (ENV['GEM_SKIP'] || "").split(/:/)
+    raise Gem::LoadError, "skipping #{gem_name}" if skip_list.include? gem_name
+
+    if gem_name.kind_of? Gem::Dependency
+      unless Gem::Deprecate.skip
+        warn "#{Gem.location_of_caller.join ':'}:Warning: Kernel.gem no longer "\
+          "accepts a Gem::Dependency object, please pass the name "\
+          "and requirements directly"
+      end
+
+      requirements = gem_name.requirement
+      gem_name = gem_name.name
+    end
+
+    spec = Gem::Dependency.new(gem_name, *requirements).to_spec
+    spec.activate if spec
+  end
+
+  private :gem
+
+end

lib/rubygems/core_ext/kernel_require.rb

@@ -0,0 +1,119 @@
+#--
+# Copyright 2006 by Chad Fowler, Rich Kilmer, Jim Weirich and others.
+# All rights reserved.
+# See LICENSE.txt for permissions.
+#++
+
+module Kernel
+
+  if defined?(gem_original_require) then
+    # Ruby ships with a custom_require, override its require
+    remove_method :require
+  else
+    ##
+    # The Kernel#require from before RubyGems was loaded.
+
+    alias gem_original_require require
+    private :gem_original_require
+  end
+
+  ##
+  # When RubyGems is required, Kernel#require is replaced with our own which
+  # is capable of loading gems on demand.
+  #
+  # When you call <tt>require 'x'</tt>, this is what happens:
+  # * If the file can be loaded from the existing Ruby loadpath, it
+  #   is.
+  # * Otherwise, installed gems are searched for a file that matches.
+  #   If it's found in gem 'y', that gem is activated (added to the
+  #   loadpath).
+  #
+  # The normal <tt>require</tt> functionality of returning false if
+  # that file has already been loaded is preserved.
+
+  def require path
+    spec = Gem.find_unresolved_default_spec(path)
+    if spec
+      Gem.remove_unresolved_default_spec(spec)
+      gem(spec.name)
+    end
+
+    # If there are no unresolved deps, then we can use just try
+    # normal require handle loading a gem from the rescue below.
+
+    if Gem::Specification.unresolved_deps.empty? then
+      return gem_original_require(path)
+    end
+
+    # If +path+ is for a gem that has already been loaded, don't
+    # bother trying to find it in an unresolved gem, just go straight
+    # to normal require.
+    #--
+    # TODO request access to the C implementation of this to speed up RubyGems
+
+    spec = Gem::Specification.find { |s|
+      s.activated? and s.contains_requirable_file? path
+    }
+
+    return gem_original_require(path) if spec
+
+    # Attempt to find +path+ in any unresolved gems...
+
+    found_specs = Gem::Specification.find_in_unresolved path
+
+    # If there are no directly unresolved gems, then try and find +path+
+    # in any gems that are available via the currently unresolved gems.
+    # For example, given:
+    #
+    #   a => b => c => d
+    #
+    # If a and b are currently active with c being unresolved and d.rb is
+    # requested, then find_in_unresolved_tree will find d.rb in d because
+    # it's a dependency of c.
+    #
+    if found_specs.empty? then
+      found_specs = Gem::Specification.find_in_unresolved_tree path
+
+      found_specs.each do |found_spec|
+        found_spec.activate
+      end
+
+    # We found +path+ directly in an unresolved gem. Now we figure out, of
+    # the possible found specs, which one we should activate.
+    else
+
+      # Check that all the found specs are just different
+      # versions of the same gem
+      names = found_specs.map(&:name).uniq
+
+      if names.size > 1 then
+        raise Gem::LoadError, "#{path} found in multiple gems: #{names.join ', '}"
+      end
+
+      # Ok, now find a gem that has no conflicts, starting
+      # at the highest version.
+      valid = found_specs.select { |s| s.conflicts.empty? }.last
+
+      unless valid then
+        le = Gem::LoadError.new "unable to find a version of '#{names.first}' to activate"
+        le.name = names.first
+        raise le
+      end
+
+      valid.activate
+    end
+
+    gem_original_require path
+  rescue LoadError => load_error
+    if load_error.message.start_with?("Could not find") or
+        (load_error.message.end_with?(path) and Gem.try_activate(path)) then
+      return gem_original_require(path)
+    end
+
+    raise load_error
+  end
+
+  private :require
+
+end
+