* lib/rubygems.rb, lib/rubygems/*, test/rubygems/*:

  Update rubygems 2.6.5 and 2.6.6.
  Release note of 2.6.5: https://github.com/rubygems/rubygems/commit/656f5d94dc888d78d0d00f3598a4fa37391aac80
  Release note of 2.6.6: https://github.com/rubygems/rubygems/commit/ccb9c3300c063f5b5656669972d24a10ef8afbf5

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55495 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

4 files changed, 21 insertions, 3 deletions

diff --git a/lib/rubygems.rb b/lib/rubygems.rb
index b041dd1042..ce9dc6a66a 100644
--- a/lib/rubygems.rb
+++ b/lib/rubygems.rb
@@ -10,7 +10,7 @@ require 'rbconfig'
 require 'thread'
 
 module Gem
-  VERSION = '2.6.4'
+  VERSION = '2.6.6'
 end
 
 # Must be first since it unloads the prelude from 1.9.2
diff --git a/lib/rubygems/commands/update_command.rb b/lib/rubygems/commands/update_command.rb
index 688e9b0e6c..f3d70a92a6 100644
--- a/lib/rubygems/commands/update_command.rb
+++ b/lib/rubygems/commands/update_command.rb
@@ -241,7 +241,7 @@ command to remove old versions.
     update_gem 'rubygems-update', version
 
     installed_gems = Gem::Specification.find_all_by_name 'rubygems-update', requirement
-    version        = installed_gems.last.version
+    version        = installed_gems.first.version
 
     install_rubygems version
   end
diff --git a/lib/rubygems/config_file.rb b/lib/rubygems/config_file.rb
index c8014814b4..3a5e7718df 100644
--- a/lib/rubygems/config_file.rb
+++ b/lib/rubygems/config_file.rb
@@ -54,7 +54,7 @@ class Gem::ConfigFile
   # For Ruby implementers to set configuration defaults.  Set in
   # rubygems/defaults/#{RUBY_ENGINE}.rb
 
-  PLATFORM_DEFAULTS = {}
+  PLATFORM_DEFAULTS = Gem.platform_defaults
 
   # :stopdoc:
 
diff --git a/lib/rubygems/defaults.rb b/lib/rubygems/defaults.rb
index 16fa96eb2d..43d57fc808 100644
--- a/lib/rubygems/defaults.rb
+++ b/lib/rubygems/defaults.rb
@@ -175,4 +175,22 @@ module Gem
               RbConfig::CONFIG['ruby_version']
   end
 
+  ##
+  # Default options for gem commands.
+  #
+  # The options here should be structured as an array of string "gem"
+  # command names as keys and a string of the default options as values.
+  #
+  # Example:
+  #
+  # def self.platform_defaults
+  #   {
+  #       'install' => '--no-rdoc --no-ri --env-shebang',
+  #       'update' => '--no-rdoc --no-ri --env-shebang'
+  #   }
+  # end
+
+  def self.platform_defaults
+    {}
+  end
 end