Added Plugin#about method to programmatically access the about.yml in a plugin (closes #10979) [lazyatom]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@9098 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

4 files changed, 52 insertions, 17 deletions

diff --git a/railties/CHANGELOG b/railties/CHANGELOG
index 048ee103a3..ac17d7a0ad 100644
--- a/railties/CHANGELOG
+++ b/railties/CHANGELOG
@@ -1,5 +1,11 @@
 *SVN*
 
+* Added Plugin#about method to programmatically access the about.yml in a plugin #10979 [lazyatom]
+
+    plugin = Rails::Plugin.new(path_to_my_plugin)
+    plugin.about["author"] # => "James Adam"
+    plugin.about["url"] # => "http://interblah.net"
+
 * Improve documentation. [Radar, Jan De Poorter, chuyeow, xaviershay, danger, miloops, Xavier Noria,  Sunny Ripert]
 
 * Added config.time_zone = 'UTC' in the default environment.rb [Geoff Buesing]
diff --git a/railties/lib/rails/plugin.rb b/railties/lib/rails/plugin.rb
index be392195d4..03fa309ca3 100644
--- a/railties/lib/rails/plugin.rb
+++ b/railties/lib/rails/plugin.rb
@@ -1,5 +1,4 @@
 module Rails
-
   # The Plugin class should be an object which provides the following methods:
   #
   # * +name+       - used during initialisation to order the plugin (based on name and
@@ -11,6 +10,12 @@ module Rails
   # These methods are expected by the Rails::Plugin::Locator and Rails::Plugin::Loader classes.
   # The default implementation returns the <tt>lib</tt> directory as its </tt>load_paths</tt>, 
   # and evaluates <tt>init.rb</tt> when <tt>load</tt> is called.
+  #
+  # You can also inspect the about.yml data programmatically:
+  #
+  #   plugin = Rails::Plugin.new(path_to_my_plugin)
+  #   plugin.about["author"] # => "James Adam"
+  #   plugin.about["url"] # => "http://interblah.net"
   class Plugin
     include Comparable
     
@@ -18,8 +23,8 @@ module Rails
     
     def initialize(directory)
       @directory = directory
-      @name = File.basename(@directory) rescue nil
-      @loaded = false
+      @name      = File.basename(@directory) rescue nil
+      @loaded    = false
     end
     
     def valid?
@@ -47,8 +52,19 @@ module Rails
     def <=>(other_plugin)
       name <=> other_plugin.name
     end
+
+    def about
+      @about ||= load_about_information
+    end
     
     private
+      def load_about_information
+        about_yml_path = File.join(@directory, "about.yml")
+        parsed_yml = File.exist?(about_yml_path) ? YAML.load(File.read(about_yml_path)) : {}
+        parsed_yml || {}
+      rescue Exception
+        {}
+      end
 
       def report_nonexistant_or_empty_plugin!
         raise LoadError, "Can not find the plugin named: #{name}"
diff --git a/railties/test/plugin_loader_test.rb b/railties/test/plugin_loader_test.rb
index ec420784a3..30eeaadf12 100644
--- a/railties/test/plugin_loader_test.rb
+++ b/railties/test/plugin_loader_test.rb
@@ -14,6 +14,8 @@ uses_mocha "Plugin Loader Tests" do
       @valid_plugin_path = plugin_fixture_path('default/stubby')
       @empty_plugin_path = plugin_fixture_path('default/empty')
       
+      @failure_tip = "It's likely someone has added a new plugin fixture without updating this list"
+      
       @loader = Rails::Plugin::Loader.new(@initializer)
     end
 
@@ -39,19 +41,16 @@ uses_mocha "Plugin Loader Tests" do
     end
     
     def test_should_find_all_availble_plugins_and_return_as_all_plugins
-      failure_tip = "It's likely someone has added a new plugin fixture without updating this list"
-      assert_plugins [:a, :acts_as_chunky_bacon, :plugin_with_no_lib_dir, :stubby], @loader.all_plugins, failure_tip      
+      assert_plugins [:a, :acts_as_chunky_bacon, :plugin_with_no_lib_dir, :stubby], @loader.all_plugins, @failure_tip      
     end
 
     def test_should_return_all_plugins_as_plugins_when_registered_plugin_list_is_untouched
-      failure_tip = "It's likely someone has added a new plugin fixture without updating this list"
-      assert_plugins [:a, :acts_as_chunky_bacon, :plugin_with_no_lib_dir, :stubby], @loader.plugins, failure_tip
+      assert_plugins [:a, :acts_as_chunky_bacon, :plugin_with_no_lib_dir, :stubby], @loader.plugins, @failure_tip
     end
     
     def test_should_return_all_plugins_as_plugins_when_registered_plugin_list_is_nil
       @configuration.plugins = nil
-      failure_tip = "It's likely someone has added a new plugin fixture without updating this list"
-      assert_plugins [:a, :acts_as_chunky_bacon, :plugin_with_no_lib_dir, :stubby], @loader.plugins, failure_tip
+      assert_plugins [:a, :acts_as_chunky_bacon, :plugin_with_no_lib_dir, :stubby], @loader.plugins, @failure_tip
     end
 
     def test_should_return_specific_plugins_named_in_config_plugins_array_if_set
@@ -68,26 +67,22 @@ uses_mocha "Plugin Loader Tests" do
     
     def test_should_load_all_plugins_in_natural_order_when_all_is_used
       only_load_the_following_plugins! [:all]
-      failure_tip = "It's likely someone has added a new plugin fixture without updating this list"
-      assert_plugins [:a, :acts_as_chunky_bacon, :plugin_with_no_lib_dir, :stubby], @loader.plugins, failure_tip
+      assert_plugins [:a, :acts_as_chunky_bacon, :plugin_with_no_lib_dir, :stubby], @loader.plugins, @failure_tip
     end
     
     def test_should_load_specified_plugins_in_order_and_then_all_remaining_plugins_when_all_is_used
       only_load_the_following_plugins! [:stubby, :acts_as_chunky_bacon, :all]
-      failure_tip = "It's likely someone has added a new plugin fixture without updating this list"
-      assert_plugins [:stubby, :acts_as_chunky_bacon, :a, :plugin_with_no_lib_dir], @loader.plugins, failure_tip
+      assert_plugins [:stubby, :acts_as_chunky_bacon, :a, :plugin_with_no_lib_dir], @loader.plugins, @failure_tip
     end
     
     def test_should_be_able_to_specify_loading_of_plugins_loaded_after_all
       only_load_the_following_plugins!  [:stubby, :all, :acts_as_chunky_bacon]
-      failure_tip = "It's likely someone has added a new plugin fixture without updating this list"
-      assert_plugins [:stubby, :a, :plugin_with_no_lib_dir, :acts_as_chunky_bacon], @loader.plugins, failure_tip
+      assert_plugins [:stubby, :a, :plugin_with_no_lib_dir, :acts_as_chunky_bacon], @loader.plugins, @failure_tip
     end
 
     def test_should_accept_plugin_names_given_as_strings
       only_load_the_following_plugins! ['stubby', 'acts_as_chunky_bacon', :a, :plugin_with_no_lib_dir]
-      failure_tip = "It's likely someone has added a new plugin fixture without updating this list"
-      assert_plugins [:stubby, :acts_as_chunky_bacon, :a, :plugin_with_no_lib_dir], @loader.plugins, failure_tip
+      assert_plugins [:stubby, :acts_as_chunky_bacon, :a, :plugin_with_no_lib_dir], @loader.plugins, @failure_tip
     end
     
     def test_should_add_plugin_load_paths_to_global_LOAD_PATH_array
diff --git a/railties/test/plugin_test.rb b/railties/test/plugin_test.rb
index 32c72f1b31..1445338f14 100644
--- a/railties/test/plugin_test.rb
+++ b/railties/test/plugin_test.rb
@@ -130,9 +130,27 @@ uses_mocha "Plugin Tests" do
       end
       assert plugin.loaded?
     end
+    
+    def test_should_make_about_yml_available_as_about_method_on_plugin
+      plugin = plugin_for(@valid_plugin_path)
+      assert_equal "Plugin Author", plugin.about['author']
+      assert_equal "1.0.0", plugin.about['version']
+    end
+    
+    def test_should_return_empty_hash_for_about_if_about_yml_is_missing
+      assert_equal({}, plugin_for(about_yml_plugin_path('plugin_without_about_yaml')).about)
+    end
+    
+    def test_should_return_empty_hash_for_about_if_about_yml_is_malformed
+      assert_equal({}, plugin_for(about_yml_plugin_path('bad_about_yml')).about)
+    end
   
     private
   
+      def about_yml_plugin_path(name)
+        File.join(File.dirname(__FILE__), 'fixtures', 'about_yml_plugins', name)
+      end
+  
       def plugin_for(path)
         Rails::Plugin.new(path)
       end