Index: lib/rubygems/commands/pristine_command.rb
===================================================================
--- lib/rubygems/commands/pristine_command.rb	(revision 42574)
+++ lib/rubygems/commands/pristine_command.rb	(working copy)
@@ -21,7 +21,8 @@ class Gem::Commands::PristineCommand < G
     end
 
     add_option('--[no-]extensions',
-               'Restore gems with extensions') do |value, options|
+               'Restore gems with extensions',
+               'in addition to regular gems') do |value, options|
       options[:extensions] = value
     end
 
@@ -43,23 +44,23 @@ class Gem::Commands::PristineCommand < G
 
   def description # :nodoc:
     <<-EOF
-The pristine command compares the installed gems with the contents of the
-cached gem and restores any files that don't match the cached gem's copy.
+The pristine command compares an installed gem with the contents of its
+cached .gem file and restores any files that don't match the cached .gem's
+copy.
+
+If you have made modifications to an installed gem, the pristine command
+will revert them.  All extensions are rebuilt and all bin stubs for the gem
+are regenerated after checking for modifications.
 
-If you have made modifications to your installed gems, the pristine command
-will revert them.  After all the gem's files have been checked all bin stubs
-for the gem are regenerated.
+If the cached gem cannot be found it will be downloaded.
 
-If the cached gem cannot be found, you will need to use `gem install` to
-revert the gem.
-
-If --no-extensions is provided pristine will not attempt to restore gems
-with extensions.
+If --no-extensions is provided pristine will not attempt to restore a gem
+with an extension.
     EOF
   end
 
   def usage # :nodoc:
-    "#{program_name} [args]"
+    "#{program_name} [GEMNAME ...]"
   end
 
   def execute
Index: lib/rubygems/core_ext/kernel_require.rb
===================================================================
--- lib/rubygems/core_ext/kernel_require.rb	(revision 42574)
+++ lib/rubygems/core_ext/kernel_require.rb	(working copy)
@@ -8,6 +8,8 @@ require 'monitor'
 
 module Kernel
 
+  RUBYGEMS_ACTIVATION_MONITOR = Monitor.new # :nodoc:
+
   if defined?(gem_original_require) then
     # Ruby ships with a custom_require, override its require
     remove_method :require
@@ -33,10 +35,8 @@ module Kernel
   # The normal <tt>require</tt> functionality of returning false if
   # that file has already been loaded is preserved.
 
-  ACTIVATION_MONITOR = Monitor.new
-
   def require path
-    ACTIVATION_MONITOR.enter
+    RUBYGEMS_ACTIVATION_MONITOR.enter
 
     spec = Gem.find_unresolved_default_spec(path)
     if spec
@@ -118,7 +118,7 @@ module Kernel
 
     raise load_error
   ensure
-    ACTIVATION_MONITOR.exit
+    RUBYGEMS_ACTIVATION_MONITOR.exit
   end
 
   private :require
Index: lib/rubygems/installer.rb
===================================================================
--- lib/rubygems/installer.rb	(revision 42574)
+++ lib/rubygems/installer.rb	(working copy)
@@ -9,6 +9,7 @@ require 'rubygems/package'
 require 'rubygems/ext'
 require 'rubygems/user_interaction'
 require 'fileutils'
+require 'thread'
 
 ##
 # The installer installs the files contained in the .gem into the Gem.home.
@@ -32,6 +33,14 @@ class Gem::Installer
   ENV_PATHS = %w[/usr/bin/env /bin/env]
 
   ##
+  # The builder shells-out to run various commands after changing the
+  # directory.  This means multiple installations cannot be allowed to build
+  # extensions in parallel as they may change each other's directories leading
+  # to broken extensions or failed installations.
+
+  CHDIR_MUTEX = Mutex.new # :nodoc:
+
+  ##
   # Raised when there is an error while building extensions.
   #
   class ExtensionBuildError < Gem::InstallError; end
@@ -675,11 +684,13 @@ TEXT
       begin
         FileUtils.mkdir_p dest_path
 
-        Dir.chdir extension_dir do
-          results = builder.build(extension, gem_dir, dest_path,
-                                  results, @build_args)
+        CHDIR_MUTEX.synchronize do
+          Dir.chdir extension_dir do
+            results = builder.build(extension, gem_dir, dest_path,
+                                    results, @build_args)
 
-          say results.join("\n") if Gem.configuration.really_verbose
+            say results.join("\n") if Gem.configuration.really_verbose
+          end
         end
       rescue
         extension_build_error(extension_dir, results.join("\n"), $@)
Index: lib/rubygems/package_task.rb
===================================================================
--- lib/rubygems/package_task.rb	(revision 42574)
+++ lib/rubygems/package_task.rb	(working copy)
@@ -96,12 +96,15 @@ class Gem::PackageTask < Rake::PackageTa
   def define
     super
 
-    task :package => [:gem]
-
     gem_file = File.basename gem_spec.cache_file
     gem_path = File.join package_dir, gem_file
     gem_dir  = File.join package_dir, gem_spec.full_name
 
+    task :package => [:gem]
+
+    directory package_dir
+    directory gem_dir
+
     desc "Build the gem file #{gem_file}"
     task :gem => [gem_path]
 
Index: lib/rubygems/specification.rb
===================================================================
--- lib/rubygems/specification.rb	(revision 42574)
+++ lib/rubygems/specification.rb	(working copy)
@@ -188,15 +188,19 @@ class Gem::Specification
   attr_reader :version
 
   ##
-  # Paths in the gem to add to <tt>$LOAD_PATH</tt> when this gem is activated.
+  # Paths in the gem to add to <code>$LOAD_PATH</code> when this gem is
+  # activated.
+  #
+  # If you have an extension you do not need to add <code>"ext"</code> to the
+  # require path, the extension build process will copy the extension files
+  # into "lib" for you.
+  #
+  # The default value is <code>"lib"</code>
   #
   # Usage:
   #
   #   # If all library files are in the root directory...
   #   spec.require_path = '.'
-  #
-  #   # If you have 'lib' and 'ext' directories...
-  #   spec.require_paths << 'ext'
 
   attr_accessor :require_paths
 
@@ -210,7 +214,7 @@ class Gem::Specification
   ##
   # A short summary of this gem's description.  Displayed in `gem list -d`.
   #
-  # The description should be more detailed than the summary.
+  # The #description should be more detailed than the summary.
   #
   # Usage:
   #
@@ -223,21 +227,23 @@ class Gem::Specification
   #
   # This is usually Gem::Platform::RUBY or Gem::Platform::CURRENT.
   #
-  # Most gems contain pure Ruby code; they should simply leave the default value
-  # in place. Some gems contain C (or other) code to be compiled into a Ruby
-  # “extension”. The should leave the default value in place unless their code
-  # will only compile on a certain type of system. Some gems consist of
-  # pre-compiled code (“binary gems”). It’s especially important that they set
-  # the platform attribute appropriately. A shortcut is to set the platform to
-  # Gem::Platform::CURRENT, which will cause the gem builder to set the platform
-  # to the appropriate value for the system on which the build is being performed.
-  #
-  # If this attribute is set to a non-default value, it will be included in the
-  # filename of the gem when it is built, e.g. fxruby-1.2.0-win32.gem.
+  # Most gems contain pure Ruby code; they should simply leave the default
+  # value in place.  Some gems contain C (or other) code to be compiled into a
+  # Ruby "extension".  The should leave the default value in place unless
+  # their code will only compile on a certain type of system.  Some gems
+  # consist of pre-compiled code ("binary gems").  It's especially important
+  # that they set the platform attribute appropriately.  A shortcut is to set
+  # the platform to Gem::Platform::CURRENT, which will cause the gem builder
+  # to set the platform to the appropriate value for the system on which the
+  # build is being performed.
+  #
+  # If this attribute is set to a non-default value, it will be included in
+  # the filename of the gem when it is built such as:
+  # nokogiri-1.6.0-x86-mingw32.gem
   #
   # Usage:
   #
-  #   spec.platform = Gem::Platform::Win32
+  #   spec.platform = Gem::Platform.local
 
   def platform= platform
     if @original_platform.nil? or
@@ -339,7 +345,7 @@ class Gem::Specification
   attr_reader :description
 
   ##
-  # A contact email for this gem
+  # A contact email address (or addresses) for this gem
   #
   # Usage:
   #
@@ -455,6 +461,8 @@ class Gem::Specification
   # Usage:
   #
   #  spec.extensions << 'ext/rmagic/extconf.rb'
+  #
+  # See Gem::Ext::Builder for information about writing extensions for gems.
 
   def extensions
     @extensions ||= []
@@ -484,6 +492,8 @@ class Gem::Specification
   # This should just be the name of your license. The full
   # text of the license should be inside of the gem when you build it.
   #
+  # You can set multiple licenses with #licenses=
+  #
   # Usage:
   #   spec.license = 'MIT'
 
@@ -520,15 +530,20 @@ class Gem::Specification
   end
 
   ##
-  # The version of ruby required by this gem
+  # The version of Ruby required by this gem.  The ruby version can be
+  # specified to the patch-level:
+  #
+  #   $ ruby -v -e 'p Gem.ruby_version'
+  #   ruby 2.0.0p247 (2013-06-27 revision 41674) [x86_64-darwin12.4.0]
+  #   #<Gem::Version "2.0.0.247">
   #
   # Usage:
   #
-  #  # If it will work with 1.8.6 or greater...
+  #  # This gem will work with 1.8.6 or greater...
   #  spec.required_ruby_version = '>= 1.8.6'
   #
-  #  # Hopefully by now:
-  #  spec.required_ruby_version = '>= 1.9.2'
+  #  # Only with ruby 2.0.x
+  #  spec.required_ruby_version = '~> 2.0'
 
   def required_ruby_version= req
     @required_ruby_version = Gem::Requirement.create req
@@ -536,7 +551,7 @@ class Gem::Specification
 
   ##
   # Lists the external (to RubyGems) requirements that must be met for this gem
-  # to work. It’s simply information for the user.
+  # to work.  It's simply information for the user.
   #
   # Usage:
   #
@@ -548,7 +563,7 @@ class Gem::Specification
   end
 
   ##
-  # A collection of unit test files. They will be loaded as unit tests when
+  # A collection of unit test files.  They will be loaded as unit tests when
   # the user requests a gem to be unit tested.
   #
   # Usage:
@@ -574,7 +589,7 @@ class Gem::Specification
   #
   # Deprecated: It is neither supported nor functional.
 
-  attr_accessor :autorequire
+  attr_accessor :autorequire # :nodoc:
 
   ##
   # Sets the default executable for this gem.
@@ -602,9 +617,12 @@ class Gem::Specification
   # The RubyGems version required by this gem
 
   attr_reader :required_rubygems_version
+
   ##
   # The rubyforge project this gem lives under.  i.e. RubyGems'
   # rubyforge_project is "rubygems".
+  #
+  # This option is deprecated.
 
   attr_accessor :rubyforge_project
 
@@ -1267,7 +1285,7 @@ class Gem::Specification
   end
 
   ##
-  # Singular reader for #authors
+  # Singular reader for #authors.  Returns the first author in the list
 
   def author
     val = authors and val.first
@@ -1275,6 +1293,8 @@ class Gem::Specification
 
   ##
   # The list of author names who wrote this gem.
+  #
+  #   spec.authors = ['Chad Fowler', 'Jim Weirich', 'Rich Kilmer']
 
   def authors
     @authors ||= []
@@ -1381,7 +1401,9 @@ class Gem::Specification
   end
 
   ##
-  # The date this gem was created. Lazily defaults to TODAY.
+  # The date this gem was created.  Lazily defaults to the current UTC date.
+  #
+  # There is no need to set this in your gem specification.
 
   def date
     @date ||= TODAY
@@ -1428,7 +1450,7 @@ class Gem::Specification
   # Deprecated: The name of the gem is assumed to be the name of the
   # executable now.  See Gem.bin_path.
 
-  def default_executable
+  def default_executable # :nodoc:
     if defined?(@default_executable) and @default_executable
       result = @default_executable
     elsif @executables and @executables.size == 1
@@ -1487,7 +1509,7 @@ class Gem::Specification
   end
 
   ##
-  # A long description of this gem
+  # A detailed description of this gem.  See also #summary
 
   def description= str
     @description = str.to_s
@@ -1676,7 +1698,7 @@ class Gem::Specification
   #
   # Formerly used to indicate this gem was RDoc-capable.
 
-  def has_rdoc
+  def has_rdoc # :nodoc:
     true
   end
 
@@ -1685,11 +1707,11 @@ class Gem::Specification
   #
   # Formerly used to indicate this gem was RDoc-capable.
 
-  def has_rdoc= ignored
+  def has_rdoc= ignored # :nodoc:
     @has_rdoc = true
   end
 
-  alias :has_rdoc? :has_rdoc
+  alias :has_rdoc? :has_rdoc # :nodoc:
 
   ##
   # True if this gem has files in test_files
Index: lib/rubygems.rb
===================================================================
--- lib/rubygems.rb	(revision 42574)
+++ lib/rubygems.rb	(working copy)
@@ -8,7 +8,7 @@
 require 'rbconfig'
 
 module Gem
-  VERSION = '2.0.6'
+  VERSION = '2.0.7'
 end
 
 # Must be first since it unloads the prelude from 1.9.2
@@ -36,9 +36,9 @@ require 'rubygems/errors'
 #
 # Further RubyGems documentation can be found at:
 #
+# * {RubyGems Guides}[http://guides.rubygems.org]
 # * {RubyGems API}[http://rubygems.rubyforge.org/rdoc] (also available from
 #   <tt>gem server</tt>)
-# * {RubyGems Bookshelf}[http://rubygem.org]
 #
 # == RubyGems Plugins
 #
Index: test/rubygems/test_gem_commands_install_command.rb
===================================================================
--- test/rubygems/test_gem_commands_install_command.rb	(revision 42574)
+++ test/rubygems/test_gem_commands_install_command.rb	(working copy)
@@ -1,5 +1,6 @@
 require 'rubygems/test_case'
 require 'rubygems/commands/install_command'
+require 'rubygems/rdoc'
 
 class TestGemCommandsInstallCommand < Gem::TestCase
 
Index: test/rubygems/test_gem_package.rb
===================================================================
--- test/rubygems/test_gem_package.rb	(revision 42574)
+++ test/rubygems/test_gem_package.rb	(working copy)
@@ -64,13 +64,16 @@ class TestGemPackage < Gem::Package::Tar
     reader = Gem::Package::TarReader.new gem_io
 
     checksums = nil
+    tar       = nil
 
     reader.each_entry do |entry|
       case entry.full_name
-      when 'checksums.yaml.gz'
+      when 'checksums.yaml.gz' then
         Zlib::GzipReader.wrap entry do |io|
           checksums = io.read
         end
+      when 'data.tar.gz' then
+        tar = entry.read
       end
     end
 
@@ -83,19 +86,14 @@ class TestGemPackage < Gem::Package::Tar
     metadata_sha1   = Digest::SHA1.hexdigest s.string
     metadata_sha512 = Digest::SHA512.hexdigest s.string
 
-    data_digests = nil
-    util_tar do |tar|
-      data_digests = package.add_contents tar
-    end
-
     expected = {
       'SHA1' => {
         'metadata.gz' => metadata_sha1,
-        'data.tar.gz' => data_digests['SHA1'].hexdigest,
+        'data.tar.gz' => Digest::SHA1.hexdigest(tar),
       },
       'SHA512' => {
         'metadata.gz' => metadata_sha512,
-        'data.tar.gz' => data_digests['SHA512'].hexdigest,
+        'data.tar.gz' => Digest::SHA512.hexdigest(tar),
       }
     }
 
Index: test/rubygems/test_gem_package_task.rb
===================================================================
--- test/rubygems/test_gem_package_task.rb	(revision 42574)
+++ test/rubygems/test_gem_package_task.rb	(working copy)
@@ -4,16 +4,37 @@ require 'rubygems/package_task'
 
 class TestGemPackageTask < Gem::TestCase
 
+  def setup
+    super
+
+    Rake.application = Rake::Application.new
+    RakeFileUtils.verbose_flag = false
+  end
+
   def test_gem_package
     gem = Gem::Specification.new do |g|
       g.name = "pkgr"
       g.version = "1.2.3"
-      g.files = Rake::FileList["x"].resolve
+
+      g.authors = %w[author]
+      g.files = %w[x]
+      g.summary = 'summary'
     end
+
     pkg = Gem::PackageTask.new(gem)  do |p|
       p.package_files << "y"
     end
-    assert_equal ["x", "y"], pkg.package_files
+
+    assert_equal %w[x y], pkg.package_files
+
+    Dir.chdir @tempdir do
+      FileUtils.touch 'x'
+      FileUtils.touch 'y'
+
+      Rake.application['package'].invoke
+
+      assert_path_exists 'pkg/pkgr-1.2.3.gem'
+    end
   end
 
   def test_gem_package_with_current_platform