Make bundle install [PATH] namespace its gems to specific rubies

lib/bundler.rb

@@ -77,10 +77,8 @@ def ui
     end
 
     def bundle_path
-      @bundle_path ||= begin
-        path = settings[:path] || Gem.dir
-        Pathname.new(path).expand_path(root)
-      end
+      # STDERR.puts settings.path
+      @bundle_path ||= Pathname.new(settings.path).expand_path(root)
     end
 
     def bin_path

lib/bundler/settings.rb

@@ -6,12 +6,12 @@ def initialize(root)
     end
 
     def [](key)
-      key = "BUNDLE_#{key.to_s.upcase}"
+      key = key_for(key)
       @config[key] || ENV[key]
     end
 
     def []=(key, value)
-      key = "BUNDLE_#{key.to_s.upcase}"
+      key = key_for(key)
       unless @config[key] == value
         @config[key] = value
         FileUtils.mkdir_p(config_file.dirname)
@@ -32,8 +32,25 @@ def without
       self[:without] ? self[:without].split(":").map { |w| w.to_sym } : []
     end
 
+    def path
+      path = ENV[key_for(:path)]
+
+      return path if path
+
+      if path = self[:path]
+        engine = defined?(RUBY_ENGINE) ? RUBY_ENGINE : "ruby"
+        "#{path}/#{engine}/#{RUBY_VERSION}"
+      else
+        Gem.dir
+      end
+    end
+
   private
 
+    def key_for(key)
+      "BUNDLE_#{key.to_s.upcase}"
+    end
+
     def config_file
       Pathname.new("#{@root}/.bundle/config")
     end

spec/install/gems/platform_spec.rb

@@ -72,6 +72,19 @@
     should_be_installed "nokogiri 1.4.2"
     should_not_be_installed "weakling"
   end
+
+  it "fetches gems again after changing the version of Ruby" do
+    gemfile <<-G
+      source "file://#{gem_repo1}"
+
+      gem "rack", "1.0.0"
+    G
+
+    bundle "install ./vendor"
+
+    engine = defined?(RUBY_ENGINE) ? RUBY_ENGINE : "ruby"
+    bundled_app("vendor/#{engine}/#{RUBY_VERSION}/gems/rack-1.0.0").should exist
+  end
 end
 
 # TODO: Don't make the tests hardcoded to a platform

spec/install/gems/simple_case_spec.rb

@@ -250,7 +250,7 @@
 
       bundle :install
 
-      bundled_app('vendor/gems/rack-1.0.0').should be_directory
+      vendored_gems('gems/rack-1.0.0').should be_directory
       should_be_installed "rack 1.0.0"
     end
 
@@ -269,7 +269,7 @@
     it "sets BUNDLE_PATH as the first argument to bundle install" do
       bundle "install ./vendor"
 
-      bundled_app('vendor/gems/rack-1.0.0').should be_directory
+      vendored_gems('gems/rack-1.0.0').should be_directory
       should_be_installed "rack 1.0.0"
     end
 
@@ -278,7 +278,7 @@
       build_gem "rack", "1.1.0", :to_system => true
       bundle "install ./vendor"
 
-      bundled_app('vendor/gems/rack-1.0.0').should be_directory
+      vendored_gems('gems/rack-1.0.0').should be_directory
       should_be_installed "rack 1.0.0"
     end
   end
@@ -341,11 +341,11 @@
         gem "rack"
       G
 
-      bundle "install vendor/gems --disable-shared-gems"
-      FileUtils.rm_rf bundled_app('vendor/gems')
+      bundle "install vendor --disable-shared-gems"
+      FileUtils.rm_rf bundled_app('vendor')
       bundle "install"
 
-      bundled_app('vendor/gems/gems/rack-1.0.0').should be_directory
+      vendored_gems('gems/rack-1.0.0').should be_directory
       should_be_installed "rack 1.0.0"
     end
   end

spec/support/path.rb

@@ -30,6 +30,11 @@ def bundled_app2(*path)
       root.join(*path)
     end
 
+    def vendored_gems(path)
+      engine = defined?(RUBY_ENGINE) ? RUBY_ENGINE : "ruby"
+      bundled_app("vendor/#{engine}/#{RUBY_VERSION}/#{path}")
+    end
+
     def cached_gem(path)
       bundled_app("vendor/cache/#{path}.gem")
     end