19 files changed, 251 insertions, 124 deletions
diff --git a/lib/rubygems/commands/owner_command.rb b/lib/rubygems/commands/owner_command.rb
index 4b99434e87..8e2271657a 100644
--- a/lib/rubygems/commands/owner_command.rb
+++ b/lib/rubygems/commands/owner_command.rb
@@ -40,7 +40,9 @@ permission to.
       options[:remove] << value
     end
 
-    add_option '-h', '--host HOST', 'Use another gemcutter-compatible host' do |value, options|
+    add_option '-h', '--host HOST',
+               'Use another gemcutter-compatible host',
+               '  (e.g. https://rubygems.org)' do |value, options|
       options[:host] = value
     end
   end
diff --git a/lib/rubygems/commands/push_command.rb b/lib/rubygems/commands/push_command.rb
index 6adeff6b30..d294cbc8df 100644
--- a/lib/rubygems/commands/push_command.rb
+++ b/lib/rubygems/commands/push_command.rb
@@ -33,7 +33,8 @@ command.  For further discussion see the help for the yank command.
     add_key_option
 
     add_option('--host HOST',
-               'Push to another gemcutter-compatible host') do |value, options|
+               'Push to another gemcutter-compatible host',
+               '  (e.g. https://rubygems.org)') do |value, options|
       options[:host] = value
     end
 
diff --git a/lib/rubygems/commands/query_command.rb b/lib/rubygems/commands/query_command.rb
index f25d120b88..813154fa23 100644
--- a/lib/rubygems/commands/query_command.rb
+++ b/lib/rubygems/commands/query_command.rb
@@ -255,22 +255,21 @@ is too hard to use.
         name_tuples.map { |n| n.version }.uniq
       else
         platforms.sort.reverse.map do |version, pls|
-          if pls == [Gem::Platform::RUBY] then
-            if options[:domain] == :remote || specs.all? { |spec| spec.is_a? Gem::Source }
-              version
-            else
-              spec = specs.select { |s| s.version == version }
-              if spec.first.default_gem?
-                "default: #{version}"
-              else
-                version
-              end
+          out = version.to_s
+
+          if options[:domain] == :local
+            default = specs.any? do |s|
+              !s.is_a?(Gem::Source) && s.version == version && s.default_gem?
             end
-          else
-            ruby = pls.delete Gem::Platform::RUBY
-            platform_list = [ruby, *pls.sort].compact
-            "#{version} #{platform_list.join ' '}"
+            out = "default: #{out}" if default
+          end
+
+          if pls != [Gem::Platform::RUBY] then
+            platform_list = [pls.delete(Gem::Platform::RUBY), *pls.sort].compact
+            out = platform_list.unshift(out).join(' ')
           end
+
+          out
         end
       end
 
diff --git a/lib/rubygems/commands/setup_command.rb b/lib/rubygems/commands/setup_command.rb
index ebb08d24d7..1fff2a7dcb 100644
--- a/lib/rubygems/commands/setup_command.rb
+++ b/lib/rubygems/commands/setup_command.rb
@@ -142,6 +142,8 @@ By default, this RubyGems will install gem as:
 
     remove_old_lib_files lib_dir
 
+    install_default_gemspec
+
     say "RubyGems #{Gem::VERSION} installed"
 
     uninstall_old_gemcutter
@@ -202,59 +204,65 @@ By default, this RubyGems will install gem as:
     end
   end
 
-  def install_executables(bin_dir)
-    say "Installing gem executable" if @verbose
 
+  def install_executables(bin_dir)
     @bin_file_names = []
 
-    Dir.chdir 'bin' do
-      bin_files = Dir['*']
-
-      bin_files.delete 'update_rubygems'
-
-      bin_files.each do |bin_file|
-        bin_file_formatted = if options[:format_executable] then
-                               Gem.default_exec_format % bin_file
-                             else
-                               bin_file
-                             end
+    {
+      'gem' => 'bin',
+      'bundler' => 'bundler/exe',
+    }.each do |tool, path|
+      say "Installing #{tool} executable" if @verbose
 
-        dest_file = File.join bin_dir, bin_file_formatted
-        bin_tmp_file = File.join Dir.tmpdir, "#{bin_file}.#{$$}"
+      Dir.chdir path do
+        bin_files = Dir['*']
 
-        begin
-          bin = File.readlines bin_file
-          bin[0] = "#!#{Gem.ruby}\n"
+        bin_files -= %w[update_rubygems bundler bundle_ruby]
 
-          File.open bin_tmp_file, 'w' do |fp|
-            fp.puts bin.join
-          end
+        bin_files.each do |bin_file|
+          bin_file_formatted = if options[:format_executable] then
+                                 Gem.default_exec_format % bin_file
+                               else
+                                 bin_file
+                               end
 
-          install bin_tmp_file, dest_file, :mode => 0755
-          @bin_file_names << dest_file
-        ensure
-          rm bin_tmp_file
-        end
+          dest_file = File.join bin_dir, bin_file_formatted
+          bin_tmp_file = File.join Dir.tmpdir, "#{bin_file}.#{$$}"
 
-        next unless Gem.win_platform?
+          begin
+            bin = File.readlines bin_file
+            bin[0] = "#!#{Gem.ruby}\n"
 
-        begin
-          bin_cmd_file = File.join Dir.tmpdir, "#{bin_file}.bat"
+            File.open bin_tmp_file, 'w' do |fp|
+              fp.puts bin.join
+            end
 
-          File.open bin_cmd_file, 'w' do |file|
-            file.puts <<-TEXT
-@ECHO OFF
-IF NOT "%~f0" == "~f0" GOTO :WinNT
-@"#{File.basename(Gem.ruby).chomp('"')}" "#{dest_file}" %1 %2 %3 %4 %5 %6 %7 %8 %9
-GOTO :EOF
-:WinNT
-@"#{File.basename(Gem.ruby).chomp('"')}" "%~dpn0" %*
-TEXT
+            install bin_tmp_file, dest_file, :mode => 0755
+            @bin_file_names << dest_file
+          ensure
+            rm bin_tmp_file
           end
 
-          install bin_cmd_file, "#{dest_file}.bat", :mode => 0755
-        ensure
-          rm bin_cmd_file
+          next unless Gem.win_platform?
+
+          begin
+            bin_cmd_file = File.join Dir.tmpdir, "#{bin_file}.bat"
+
+            File.open bin_cmd_file, 'w' do |file|
+              file.puts <<-TEXT
+  @ECHO OFF
+  IF NOT "%~f0" == "~f0" GOTO :WinNT
+  @"#{File.basename(Gem.ruby).chomp('"')}" "#{dest_file}" %1 %2 %3 %4 %5 %6 %7 %8 %9
+  GOTO :EOF
+  :WinNT
+  @"#{File.basename(Gem.ruby).chomp('"')}" "%~dpn0" %*
+  TEXT
+            end
+
+            install bin_cmd_file, "#{dest_file}.bat", :mode => 0755
+          ensure
+            rm bin_cmd_file
+          end
         end
       end
     end
@@ -269,18 +277,23 @@ TEXT
   end
 
   def install_lib(lib_dir)
-    say "Installing RubyGems" if @verbose
-
-    lib_files = rb_files_in 'lib'
-    pem_files = pem_files_in 'lib'
-
-    Dir.chdir 'lib' do
-      lib_files.each do |lib_file|
-        install_file lib_file, lib_dir
-      end
+    {
+      'RubyGems' => 'lib',
+      'Bundler' => 'bundler/lib'
+    }.each do |tool, path|
+      say "Installing #{tool}" if @verbose
+
+      lib_files = rb_files_in path
+      pem_files = pem_files_in path
+
+      Dir.chdir path do
+        lib_files.each do |lib_file|
+          install_file lib_file, lib_dir
+        end
 
-      pem_files.each do |pem_file|
-        install_file pem_file, lib_dir
+        pem_files.each do |pem_file|
+          install_file pem_file, lib_dir
+        end
       end
     end
   end
@@ -326,6 +339,19 @@ TEXT
     return false
   end
 
+  def install_default_gemspec
+    Dir.chdir("bundler") do
+      bundler_spec = Gem::Specification.load("bundler.gemspec")
+      bundler_spec.files = Dir["{*.md,{lib,exe,man}/**/*}"]
+      bundler_spec.executables -= %w[bundler bundle_ruby]
+      Dir.entries(Gem::Specification.default_specifications_dir).
+        select {|gs| gs.start_with?("bundler-") }.
+        each {|gs| File.delete(File.join(Gem::Specification.default_specifications_dir, gs)) }
+      default_spec_path = File.join(Gem::Specification.default_specifications_dir, "#{bundler_spec.full_name}.gemspec")
+      Gem.write_binary(default_spec_path, bundler_spec.to_ruby)
+    end
+  end
+
   def make_destination_dirs(install_destdir)
     lib_dir, bin_dir = Gem.default_rubygems_dirs
 
@@ -416,23 +442,27 @@ abort "#{deprecation_message}"
   end
 
   def remove_old_lib_files lib_dir
-    rubygems_dir = File.join lib_dir, 'rubygems'
-    lib_files = rb_files_in 'lib/rubygems'
+    {
+      File.join(lib_dir, 'rubygems') => 'lib/rubygems',
+      File.join(lib_dir, 'bundler') => 'bundler/lib/bundler',
+    }.each do |old_lib_dir, new_lib_dir|
+      lib_files = rb_files_in(new_lib_dir)
 
-    old_lib_files = rb_files_in rubygems_dir
+      old_lib_files = rb_files_in(old_lib_dir)
 
-    to_remove = old_lib_files - lib_files
+      to_remove = old_lib_files - lib_files
 
-    to_remove.delete_if do |file|
-      file.start_with? 'defaults'
-    end
+      to_remove.delete_if do |file|
+        file.start_with? 'defaults'
+      end
 
-    Dir.chdir rubygems_dir do
-      to_remove.each do |file|
-        FileUtils.rm_f file
+      Dir.chdir old_lib_dir do
+        to_remove.each do |file|
+          FileUtils.rm_f file
 
-        warn "unable to remove old file #{file} please remove it by hand" if
-          File.exist? file
+          warn "unable to remove old file #{file} please remove it by hand" if
+            File.exist? file
+        end
       end
     end
   end
@@ -481,4 +511,3 @@ abort "#{deprecation_message}"
   end
 
 end
-
diff --git a/lib/rubygems/commands/yank_command.rb b/lib/rubygems/commands/yank_command.rb
index 0d6575b272..36809cbd57 100644
--- a/lib/rubygems/commands/yank_command.rb
+++ b/lib/rubygems/commands/yank_command.rb
@@ -42,7 +42,8 @@ as the reason for the removal request.
     add_platform_option("remove")
 
     add_option('--host HOST',
-               'Yank from another gemcutter-compatible host') do |value, options|
+               'Yank from another gemcutter-compatible host',
+               '  (e.g. https://rubygems.org)') do |value, options|
       options[:host] = value
     end
 
diff --git a/lib/rubygems/config_file.rb b/lib/rubygems/config_file.rb
index 3a5e7718df..c95d7dd1f1 100644
--- a/lib/rubygems/config_file.rb
+++ b/lib/rubygems/config_file.rb
@@ -144,6 +144,10 @@ class Gem::ConfigFile
   attr_accessor :ssl_ca_cert
 
   ##
+  # sources to look for gems
+  attr_accessor :sources
+
+  ##
   # Path name of directory or file of openssl client certificate, used for remote https connection with client authentication
 
   attr_reader :ssl_client_cert
@@ -216,6 +220,7 @@ class Gem::ConfigFile
     @update_sources             = @hash[:update_sources]             if @hash.key? :update_sources
     @verbose                    = @hash[:verbose]                    if @hash.key? :verbose
     @disable_default_gem_server = @hash[:disable_default_gem_server] if @hash.key? :disable_default_gem_server
+    @sources                    = @hash[:sources]                    if @hash.key? :sources
 
     @ssl_verify_mode  = @hash[:ssl_verify_mode]  if @hash.key? :ssl_verify_mode
     @ssl_ca_cert      = @hash[:ssl_ca_cert]      if @hash.key? :ssl_ca_cert
@@ -224,7 +229,6 @@ class Gem::ConfigFile
     @api_keys         = nil
     @rubygems_api_key = nil
 
-    Gem.sources = @hash[:sources] if @hash.key? :sources
     handle_arguments arg_list
   end
 
diff --git a/lib/rubygems/core_ext/kernel_require.rb b/lib/rubygems/core_ext/kernel_require.rb
index aa56ab5ec4..d23a6fe90a 100755
--- a/lib/rubygems/core_ext/kernel_require.rb
+++ b/lib/rubygems/core_ext/kernel_require.rb
@@ -41,8 +41,7 @@ module Kernel
 
     path = path.to_path if path.respond_to? :to_path
 
-    spec = Gem.find_unresolved_default_spec(path)
-    if spec
+    if spec = Gem.find_unresolved_default_spec(path)
       Gem.remove_unresolved_default_spec(spec)
       gem(spec.name)
     end
@@ -61,12 +60,10 @@ module Kernel
     #--
     # TODO request access to the C implementation of this to speed up RubyGems
 
-    spec = Gem::Specification.find_active_stub_by_path path
-
-    begin
+    if Gem::Specification.find_active_stub_by_path(path)
       RUBYGEMS_ACTIVATION_MONITOR.exit
       return gem_original_require(path)
-    end if spec
+    end
 
     # Attempt to find +path+ in any unresolved gems...
 
@@ -104,7 +101,7 @@ module Kernel
 
       # Ok, now find a gem that has no conflicts, starting
       # at the highest version.
-      valid = found_specs.reject { |s| s.has_conflicts? }.first
+      valid = found_specs.find { |s| !s.has_conflicts? }
 
       unless valid then
         le = Gem::LoadError.new "unable to find a version of '#{names.first}' to activate"
@@ -138,4 +135,3 @@ module Kernel
   private :require
 
 end
-
diff --git a/lib/rubygems/exceptions.rb b/lib/rubygems/exceptions.rb
index 9089eae4d5..b7528761fc 100644
--- a/lib/rubygems/exceptions.rb
+++ b/lib/rubygems/exceptions.rb
@@ -154,6 +154,12 @@ class Gem::ImpossibleDependenciesError < Gem::Exception
 end
 
 class Gem::InstallError < Gem::Exception; end
+class Gem::RuntimeRequirementNotMetError < Gem::InstallError
+  attr_accessor :suggestion
+  def message
+    [suggestion, super].compact.join("\n\t")
+  end
+end
 
 ##
 # Potentially raised when a specification is validated.
diff --git a/lib/rubygems/installer.rb b/lib/rubygems/installer.rb
index 6e77185547..bd2eed19de 100644
--- a/lib/rubygems/installer.rb
+++ b/lib/rubygems/installer.rb
@@ -282,18 +282,23 @@ class Gem::Installer
 
     run_pre_install_hooks
 
+    # Set loaded_from to ensure extension_dir is correct
+    if @options[:install_as_default] then
+      spec.loaded_from = default_spec_file
+    else
+      spec.loaded_from = spec_file
+    end
+
     # Completely remove any previous gem files
     FileUtils.rm_rf gem_dir
     FileUtils.rm_rf spec.extension_dir
 
     FileUtils.mkdir_p gem_dir
 
-    if @options[:install_as_default]
-      spec.loaded_from = default_spec_file
+    if @options[:install_as_default] then
       extract_bin
       write_default_spec
     else
-      spec.loaded_from = spec_file
       extract_files
 
       build_extensions
@@ -603,7 +608,8 @@ class Gem::Installer
   def ensure_required_ruby_version_met # :nodoc:
     if rrv = spec.required_ruby_version then
       unless rrv.satisfied_by? Gem.ruby_version then
-        raise Gem::InstallError, "#{spec.name} requires Ruby version #{rrv}."
+        raise Gem::RuntimeRequirementNotMetError,
+          "#{spec.name} requires Ruby version #{rrv}."
       end
     end
   end
@@ -611,7 +617,7 @@ class Gem::Installer
   def ensure_required_rubygems_version_met # :nodoc:
     if rrgv = spec.required_rubygems_version then
       unless rrgv.satisfied_by? Gem.rubygems_version then
-        raise Gem::InstallError,
+        raise Gem::RuntimeRequirementNotMetError,
           "#{spec.name} requires RubyGems version #{rrgv}. " +
           "Try 'gem update --system' to update RubyGems itself."
       end
diff --git a/lib/rubygems/remote_fetcher.rb b/lib/rubygems/remote_fetcher.rb
index da4db724a1..e6a13d4b8c 100644
--- a/lib/rubygems/remote_fetcher.rb
+++ b/lib/rubygems/remote_fetcher.rb
@@ -260,6 +260,9 @@ class Gem::RemoteFetcher
          Net::HTTPTemporaryRedirect then
       raise FetchError.new('too many redirects', uri) if depth > 10
 
+      unless location = response['Location']
+        raise FetchError.new("redirecting but no redirect location was given", uri)
+      end
       location = URI.parse response['Location']
 
       if https?(uri) && !https?(location)
diff --git a/lib/rubygems/request_set.rb b/lib/rubygems/request_set.rb
index 5541e64b88..49e56ae6fb 100644
--- a/lib/rubygems/request_set.rb
+++ b/lib/rubygems/request_set.rb
@@ -163,9 +163,26 @@ class Gem::RequestSet
         end
       end
 
-      spec = req.spec.install options do |installer|
-        yield req, installer if block_given?
-      end
+      spec =
+        begin
+          req.spec.install options do |installer|
+            yield req, installer if block_given?
+          end
+        rescue Gem::RuntimeRequirementNotMetError => e
+          recent_match = req.spec.set.find_all(req.request).sort_by(&:version).reverse_each.find do |s|
+            s = s.spec
+            s.required_ruby_version.satisfied_by?(Gem.ruby_version) && s.required_rubygems_version.satisfied_by?(Gem.rubygems_version)
+          end
+          if recent_match
+            suggestion = "The last version of #{req.request} to support your ruby & rubygems was #{recent_match.version}. Try installing it with `gem install #{recent_match.name} -v #{recent_match.version}`"
+            suggestion += " and then running the current command again" unless @always_install.any? { |spec| spec == req.spec.spec }
+          else
+            suggestion = "There are no versions of #{req.request} compatible with your ruby & rubygems"
+            suggestion += ". Maybe try installing an older version of the gem you're looking for?" unless @always_install.any? { |spec| spec == req.spec.spec }
+          end
+          e.suggestion = suggestion
+          raise
+        end
 
       requests << spec
     end
diff --git a/lib/rubygems/resolver.rb b/lib/rubygems/resolver.rb
index 50a547e1be..0a3276daab 100644
--- a/lib/rubygems/resolver.rb
+++ b/lib/rubygems/resolver.rb
@@ -233,8 +233,29 @@ class Gem::Resolver
       exc.errors = @set.errors
       raise exc
     end
-    possibles.sort_by { |s| [s.source, s.version, Gem::Platform.local =~ s.platform ? 1 : 0] }.
-      map { |s| ActivationRequest.new s, dependency, [] }
+
+    sources = []
+
+    groups = Hash.new { |hash, key| hash[key] = [] }
+
+    possibles.each do |spec|
+      source = spec.source
+
+      sources << source unless sources.include? source
+
+      groups[source] << spec
+    end
+
+    activation_requests = []
+
+    sources.sort.each do |source|
+      groups[source].
+        sort_by { |spec| [spec.version, Gem::Platform.local =~ spec.platform ? 1 : 0] }.
+        map { |spec| ActivationRequest.new spec, dependency, [] }.
+        each { |activation_request| activation_requests << activation_request }
+    end
+
+    activation_requests
   end
 
   def dependencies_for(specification)
diff --git a/lib/rubygems/resolver/molinillo/lib/molinillo/gem_metadata.rb b/lib/rubygems/resolver/molinillo/lib/molinillo/gem_metadata.rb
index 1a82da0e7a..4170b00af0 100644
--- a/lib/rubygems/resolver/molinillo/lib/molinillo/gem_metadata.rb
+++ b/lib/rubygems/resolver/molinillo/lib/molinillo/gem_metadata.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 module Gem::Resolver::Molinillo
   # The version of Gem::Resolver::Molinillo.
-  VERSION = '0.5.0'.freeze
+  VERSION = '0.5.1'.freeze
 end
diff --git a/lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb b/lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb
index 1fb7a1e921..e6565119ef 100644
--- a/lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb
+++ b/lib/rubygems/resolver/molinillo/lib/molinillo/resolution.rb
@@ -184,6 +184,8 @@ module Gem::Resolver::Molinillo
           raise VersionConflict.new(c) unless state
           activated.rewind_to(sliced_states.first || :initial_state) if sliced_states
           state.conflicts = c
+          index = states.size - 1
+          @parent_of.reject! { |_, i| i >= index }
         end
       end
 
@@ -209,7 +211,10 @@ module Gem::Resolver::Molinillo
       # @return [Object] the requirement that led to `requirement` being added
       #   to the list of requirements.
       def parent_of(requirement)
-        @parent_of[requirement]
+        return unless requirement
+        return unless index = @parent_of[requirement]
+        return unless parent_state = @states[index]
+        parent_state.requirement
       end
 
       # @return [Object] the requirement that led to a version of a possibility
@@ -418,7 +423,8 @@ module Gem::Resolver::Molinillo
         debug(depth) { "Requiring nested dependencies (#{nested_dependencies.join(', ')})" }
         nested_dependencies.each do |d|
           activated.add_child_vertex(name_for(d), nil, [name_for(activated_spec)], d)
-          @parent_of[d] = requirement
+          parent_index = states.size - 1
+          @parent_of[d] ||= parent_index
         end
 
         push_state_for_requirements(requirements + nested_dependencies, !nested_dependencies.empty?)
diff --git a/lib/rubygems/source.rb b/lib/rubygems/source.rb
index 85f5268fa3..4f07beb1f4 100644
--- a/lib/rubygems/source.rb
+++ b/lib/rubygems/source.rb
@@ -67,7 +67,11 @@ class Gem::Source
 
       return -1 if !other.uri
 
-      @uri.to_s <=> other.uri.to_s
+      # Returning 1 here ensures that when sorting a list of sources, the
+      # original ordering of sources supplied by the user is preserved.
+      return 1 unless @uri.to_s == other.uri.to_s
+
+      0
     else
       nil
     end
diff --git a/lib/rubygems/spec_fetcher.rb b/lib/rubygems/spec_fetcher.rb
index 755d4be1eb..919276e113 100644
--- a/lib/rubygems/spec_fetcher.rb
+++ b/lib/rubygems/spec_fetcher.rb
@@ -184,10 +184,10 @@ class Gem::SpecFetcher
   # Suggests gems based on the supplied +gem_name+. Returns an array of
   # alternative gem names.
 
-  def suggest_gems_from_name gem_name
+  def suggest_gems_from_name(gem_name, type = :latest)
     gem_name        = gem_name.downcase.tr('_-', '')
     max             = gem_name.size / 2
-    names           = available_specs(:latest).first.values.flatten(1)
+    names           = available_specs(type).first.values.flatten(1)
 
     matches = names.map { |n|
       next unless n.match_platform?
@@ -201,7 +201,11 @@ class Gem::SpecFetcher
       [n.name, distance]
     }.compact
 
-    matches = matches.uniq.sort_by { |name, dist| dist }
+    matches = if matches.empty? && type != :prerelease
+      suggest_gems_from_name gem_name, :prerelease
+    else
+      matches.uniq.sort_by { |name, dist| dist }
+    end
 
     matches.first(5).map { |name, dist| name }
   end
diff --git a/lib/rubygems/test_case.rb b/lib/rubygems/test_case.rb
index f7ae97cd8d..3e1924ac63 100644
--- a/lib/rubygems/test_case.rb
+++ b/lib/rubygems/test_case.rb
@@ -25,6 +25,7 @@ unless Gem::Dependency.new('rdoc', '>= 3.10').matching_specs.empty?
   gem 'json'
 end
 
+require 'bundler'
 require 'minitest/autorun'
 
 require 'rubygems/deprecate'
@@ -222,17 +223,25 @@ class Gem::TestCase < MiniTest::Unit::TestCase
     @orig_gem_vendor = ENV['GEM_VENDOR']
     @orig_gem_spec_cache = ENV['GEM_SPEC_CACHE']
     @orig_rubygems_gemdeps = ENV['RUBYGEMS_GEMDEPS']
+    @orig_bundle_gemfile   = ENV['BUNDLE_GEMFILE']
     @orig_rubygems_host = ENV['RUBYGEMS_HOST']
+    @orig_bundle_disable_postit = ENV['BUNDLE_DISABLE_POSTIT']
     ENV.keys.find_all { |k| k.start_with?('GEM_REQUIREMENT_') }.each do |k|
       ENV.delete k
     end
     @orig_gem_env_requirements = ENV.to_hash
 
     ENV['GEM_VENDOR'] = nil
+    ENV['BUNDLE_DISABLE_POSTIT'] = 'true'
 
     @current_dir = Dir.pwd
     @fetcher     = nil
-    @ui          = Gem::MockGemUi.new
+
+    Bundler.ui                     = Bundler::UI::Silent.new
+    @ui                            = Gem::MockGemUi.new
+    # This needs to be a new instance since we call use_ui(@ui) when we want to
+    # capture output
+    Gem::DefaultUserInteraction.ui = Gem::MockGemUi.new
 
     tmpdir = File.expand_path Dir.tmpdir
     tmpdir.untaint
@@ -323,6 +332,7 @@ class Gem::TestCase < MiniTest::Unit::TestCase
     Gem.loaded_specs.clear
     Gem.clear_default_specs
     Gem::Specification.unresolved_deps.clear
+    Bundler.reset!
 
     Gem.configuration.verbose = true
     Gem.configuration.update_sources = true
@@ -394,7 +404,9 @@ class Gem::TestCase < MiniTest::Unit::TestCase
     ENV['GEM_VENDOR'] = @orig_gem_vendor
     ENV['GEM_SPEC_CACHE'] = @orig_gem_spec_cache
     ENV['RUBYGEMS_GEMDEPS'] = @orig_rubygems_gemdeps
+    ENV['BUNDLE_GEMFILE']   = @orig_bundle_gemfile
     ENV['RUBYGEMS_HOST'] = @orig_rubygems_host
+    ENV['BUNDLE_DISABLE_POSTIT'] = @orig_bundle_disable_postit
 
     Gem.ruby = @orig_ruby if @orig_ruby
 
diff --git a/lib/rubygems/user_interaction.rb b/lib/rubygems/user_interaction.rb
index 390d0f2aea..cacd782e08 100644
--- a/lib/rubygems/user_interaction.rb
+++ b/lib/rubygems/user_interaction.rb
@@ -7,11 +7,6 @@
 
 require 'rubygems/util'
 
-begin
-  require 'io/console'
-rescue LoadError
-end
-
 ##
 # Module that defines the default UserInteraction.  Any class including this
 # module will have access to the +ui+ method that returns the default UI.
@@ -314,12 +309,21 @@ class Gem::StreamUI
     password
   end
 
-  if IO.method_defined?(:noecho) then
-    def _gets_noecho
-      @ins.noecho {@ins.gets}
+  def require_io_console
+    @require_io_console ||= begin
+      begin
+        require 'io/console'
+      rescue LoadError
+      end
+      true
     end
-  elsif Gem.win_platform?
-    def _gets_noecho
+  end
+
+  def _gets_noecho
+    require_io_console
+    if IO.method_defined?(:noecho) then
+      @ins.noecho {@ins.gets}
+    elsif Gem.win_platform?
       require "Win32API"
       password = ''
 
@@ -332,9 +336,7 @@ class Gem::StreamUI
         end
       end
       password
-    end
-  else
-    def _gets_noecho
+    else
       system "stty -echo"
       begin
         @ins.gets
diff --git a/lib/rubygems/version.rb b/lib/rubygems/version.rb
index 2f6cfae6ed..6eeaafdcc5 100644
--- a/lib/rubygems/version.rb
+++ b/lib/rubygems/version.rb
@@ -237,7 +237,7 @@ class Gem::Version
   end
 
   def hash # :nodoc:
-    @version.hash
+    canonical_segments.hash
   end
 
   def init_with coder # :nodoc:
@@ -331,7 +331,7 @@ class Gem::Version
 
   def <=> other
     return unless Gem::Version === other
-    return 0 if @version == other._version
+    return 0 if @version == other._version || canonical_segments == other.canonical_segments
 
     lhsegments = _segments
     rhsegments = other._segments
@@ -356,6 +356,13 @@ class Gem::Version
     return 0
   end
 
+  def canonical_segments
+    @canonical_segments ||=
+      _split_segments.map! do |segments|
+        segments.reverse_each.drop_while {|s| s == 0 }.reverse
+      end.reduce(&:concat)
+  end
+
   protected
 
   def _version
@@ -371,4 +378,11 @@ class Gem::Version
       /^\d+$/ =~ s ? s.to_i : s
     end.freeze
   end
+
+  def _split_segments
+    string_start = _segments.index {|s| s.is_a?(String) }
+    string_segments  = segments
+    numeric_segments = string_segments.slice!(0, string_start || string_segments.size)
+    return numeric_segments, string_segments
+  end
 end