config.gem_paths = ["path1","path2",...] for environment.rb

there seems to be 3 main times when rails will want to load up and work with vendor/gems.

1) the Rake tasks to freeze / unfreeze gems
2) the Rails startup code in the very beginning, will try to load once the gems
3) the time after environment.rb and *after* the config,gem in run initializer do config.

This commit works in doing muliple paths for 3), but not 1) and 2).
You can put in my environment.rb a configuration line like this:

config.gem_paths = ["#{PLUGIN_PATH}/vendor/gems"]

Inside of the do |config| loop

railties/environments/boot.rb

@@ -44,7 +44,7 @@ class VendorBoot < Boot
     def load_initializer
       require "#{RAILS_ROOT}/vendor/rails/railties/lib/initializer"
       Rails::Initializer.run(:install_gem_spec_stubs)
-      Rails::GemDependency.add_frozen_gem_path
+      Rails::Initializer.run(:add_frozen_gem_paths)
     end
   end
 

railties/lib/initializer.rb

@@ -235,6 +235,10 @@ def install_gem_spec_stubs
       end
     end
 
+    def add_frozen_gem_paths
+      Rails::GemDependency.add_frozen_gem_paths(configuration.gem_paths)
+    end
+
     # Set the <tt>$LOAD_PATH</tt> based on the value of
     # Configuration#load_paths. Duplicates are removed.
     def set_load_path
@@ -295,13 +299,16 @@ def add_plugin_load_paths
     end
 
     def add_gem_load_paths
-      Rails::GemDependency.add_frozen_gem_path
+      Rails::GemDependency.add_frozen_gem_paths(configuration.gem_paths)
       unless @configuration.gems.empty?
         require "rubygems"
-        @configuration.gems.each { |gem| gem.add_load_paths }
+        @configuration.gems.each { |gem| gem.add_load_paths(configuration.gem_paths) }
       end
     end
 
+    # Loads all gems in <tt>config.gem_paths</tt>.  <tt>gem_paths</tt> defaults 
+    # to <tt>vendor/gems</tt> but may also be set to a list of paths, such as
+    #   config.gem_paths = ["#{RAILS_ROOT}/lib/gems", "#{RAILS_ROOT}/vendor/gems"]
     def load_gems
       unless $gems_rake_task
         @configuration.gems.each { |gem| gem.load }
@@ -797,6 +804,11 @@ def reload_plugins?
     # You can add gems with the #gem method.
     attr_accessor :gems
 
+    # The path to the root of the gems directory. By default, it is <tt>vendor/gems</tt>.
+    # May also be set to a list of paths, in the enrivonment.rb, do |config| block:
+    #   config.gem_paths = ["#{RAILS_ROOT}/lib/gems", "#{RAILS_ROOT}/vendor/gems"]
+    attr_accessor :gem_paths
+
     # Adds a single Gem dependency to the rails application. By default, it will require
     # the library with the same name as the gem. Use :lib to specify a different name.
     #
@@ -854,6 +866,7 @@ def initialize
       self.database_configuration_file  = default_database_configuration_file
       self.routes_configuration_file    = default_routes_configuration_file
       self.gems                         = default_gems
+      self.gem_paths                    = default_gem_paths
       self.i18n                         = default_i18n
 
       for framework in default_frameworks
@@ -1077,6 +1090,10 @@ def default_gems
         []
       end
 
+      def default_gem_paths
+        [Rails::GemDependency.default_gem_path]
+      end
+
       def default_i18n
         i18n = Rails::OrderedOptions.new
         i18n.load_path = []

railties/lib/rails/backtrace_cleaner.rb

@@ -34,7 +34,7 @@ def add_gem_filters
           add_filter { |line| line.sub(/(#{path})\/gems\/([a-z]+)-([0-9.]+)\/(.*)/, '\2 (\3) \4')}
         end
 
-        vendor_gems_path = Rails::GemDependency.unpacked_path.sub("#{RAILS_ROOT}/",'')
+        vendor_gems_path = Rails::GemDependency.default_gem_path.sub("#{RAILS_ROOT}/",'')
         add_filter { |line| line.sub(/(#{vendor_gems_path})\/([a-z]+)-([0-9.]+)\/(.*)/, '\2 (\3) [v] \4')}
       end
   end

railties/lib/rails/gem_dependency.rb

@@ -10,22 +10,29 @@ module Rails
   class GemDependency < Gem::Dependency
     attr_accessor :lib, :source, :dep
 
-    def self.unpacked_path
-      @unpacked_path ||= File.join(RAILS_ROOT, 'vendor', 'gems')
+    def self.default_gem_path
+      @default_gem_path ||= File.join(RAILS_ROOT, 'vendor', 'gems')
     end
 
     @@framework_gems = {}
+    @@loaded_paths = []
 
     def self.add_frozen_gem_path
-      @@paths_loaded ||= begin
-        source_index = Rails::VendorGemSourceIndex.new(Gem.source_index)
+      add_frozen_gem_paths([default_gem_path])
+    end
+
+    def self.add_frozen_gem_paths(gem_paths)
+      gem_paths = gem_paths - [default_gem_path] unless gem_paths == [default_gem_path]
+      new_paths = gem_paths - ( @@loaded_paths & gem_paths )
+      unless new_paths.empty?
+        source_index = Rails::VendorGemSourceIndex.new(Gem.source_index, gem_paths)
         Gem.clear_paths
         Gem.source_index = source_index
         # loaded before us - we can't change them, so mark them
         Gem.loaded_specs.each do |name, spec|
           @@framework_gems[name] = spec
         end
-        true
+        @@loaded_paths = @@loaded_paths + new_paths
       end
     end
 
@@ -56,16 +63,16 @@ def initialize(name, options = {})
       super(name, req)
     end
 
-    def add_load_paths
-      self.class.add_frozen_gem_path
+    def add_load_paths(gem_paths)
+      self.class.add_frozen_gem_paths(gem_paths)
       return if @loaded || @load_paths_added
       if framework_gem?
         @load_paths_added = @loaded = @frozen = true
         return
       end
       gem self
       @spec = Gem.loaded_specs[name]
-      @frozen = @spec.loaded_from.include?(self.class.unpacked_path) if @spec
+      @frozen = @spec.loaded_from.include?(self.class.default_gem_path) if @spec
       @load_paths_added = true
     rescue Gem::LoadError
     end
@@ -280,7 +287,7 @@ def unpack_command
       end
 
       def unpack_base
-        Rails::GemDependency.unpacked_path
+        Rails::GemDependency.default_gem_path
       end
 
       def unpacked_gem_directory

railties/lib/rails/vendor_gem_source_index.rb

@@ -1,5 +1,6 @@
 require 'rubygems'
 require 'yaml'
+require 'active_support/core_ext/enumerable'
 
 module Rails
 
@@ -12,8 +13,10 @@ class VendorGemSourceIndex
 
     attr_reader :installed_source_index
     attr_reader :vendor_source_index
+    attr_reader :gem_paths
 
     @@silence_spec_warnings = false
+    # @@silence_spec_warnings = true
 
     def self.silence_spec_warnings
       @@silence_spec_warnings
@@ -23,9 +26,9 @@ def self.silence_spec_warnings=(v)
       @@silence_spec_warnings = v
     end
 
-    def initialize(installed_index, vendor_dir=Rails::GemDependency.unpacked_path)
+    def initialize(installed_index, gem_paths)
       @installed_source_index = installed_index
-      @vendor_dir = vendor_dir
+      @gem_paths = gem_paths
       refresh!
     end
 
@@ -42,7 +45,8 @@ def refresh!
       end
 
       # load specifications from vendor/gems
-      Dir[File.join(Rails::GemDependency.unpacked_path, '*')].each do |d|
+      gem_unpacked_paths = gem_paths.sum { |path| Dir["#{path}/**"] }
+      Dir.glob( gem_unpacked_paths ).each do |d|
         dir_name = File.basename(d)
         dir_version = version_for_dir(dir_name)
         spec = load_specification(d)

railties/test/backtrace_cleaner_test.rb

@@ -53,7 +53,7 @@ def setup
   end
 
   test "should format vendor gems correctly" do
-    @backtrace = [ "#{Rails::GemDependency.unpacked_path}/nosuchgem-1.2.3/lib/foo.rb" ]
+    @backtrace = [ "#{Rails::GemDependency.default_gem_path}/nosuchgem-1.2.3/lib/foo.rb" ]
     @result = @cleaner.clean(@backtrace)
     assert_equal "nosuchgem (1.2.3) [v] lib/foo.rb", @result[0]
   end