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Diffstat (limited to 'vendor/plugins/coderay-0.9.0/lib/coderay/helpers/plugin.rb')
| -rw-r--r-- | vendor/plugins/coderay-0.9.0/lib/coderay/helpers/plugin.rb | 347 |
1 files changed, 347 insertions, 0 deletions
diff --git a/vendor/plugins/coderay-0.9.0/lib/coderay/helpers/plugin.rb b/vendor/plugins/coderay-0.9.0/lib/coderay/helpers/plugin.rb new file mode 100644 index 000000000..fba8bb4da --- /dev/null +++ b/vendor/plugins/coderay-0.9.0/lib/coderay/helpers/plugin.rb @@ -0,0 +1,347 @@ +module CodeRay + +# = PluginHost +# +# A simple subclass plugin system. +# +# Example: +# class Generators < PluginHost +# plugin_path 'app/generators' +# end +# +# class Generator +# extend Plugin +# PLUGIN_HOST = Generators +# end +# +# class FancyGenerator < Generator +# register_for :fancy +# end +# +# Generators[:fancy] #-> FancyGenerator +# # or +# CodeRay.require_plugin 'Generators/fancy' +module PluginHost + + # Raised if Encoders::[] fails because: + # * a file could not be found + # * the requested Encoder is not registered + PluginNotFound = Class.new Exception + HostNotFound = Class.new Exception + + PLUGIN_HOSTS = [] + PLUGIN_HOSTS_BY_ID = {} # dummy hash + + # Loads all plugins using list and load. + def load_all + for plugin in list + load plugin + end + end + + # Returns the Plugin for +id+. + # + # Example: + # yaml_plugin = MyPluginHost[:yaml] + def [] id, *args, &blk + plugin = validate_id(id) + begin + plugin = plugin_hash.[] plugin, *args, &blk + end while plugin.is_a? Symbol + plugin + end + + # Alias for +[]+. + alias load [] + + def require_helper plugin_id, helper_name + path = path_to File.join(plugin_id, helper_name) + require path + end + + class << self + + # Adds the module/class to the PLUGIN_HOSTS list. + def extended mod + PLUGIN_HOSTS << mod + end + + # Warns you that you should not #include this module. + def included mod + warn "#{name} should not be included. Use extend." + end + + # Find the PluginHost for host_id. + def host_by_id host_id + unless PLUGIN_HOSTS_BY_ID.default_proc + ph = Hash.new do |h, a_host_id| + for host in PLUGIN_HOSTS + h[host.host_id] = host + end + h.fetch a_host_id, nil + end + PLUGIN_HOSTS_BY_ID.replace ph + end + PLUGIN_HOSTS_BY_ID[host_id] + end + + end + + # The path where the plugins can be found. + def plugin_path *args + unless args.empty? + @plugin_path = File.expand_path File.join(*args) + load_map + end + @plugin_path + end + + # The host's ID. + # + # If PLUGIN_HOST_ID is not set, it is simply the class name. + def host_id + if self.const_defined? :PLUGIN_HOST_ID + self::PLUGIN_HOST_ID + else + name + end + end + + # Map a plugin_id to another. + # + # Usage: Put this in a file plugin_path/_map.rb. + # + # class MyColorHost < PluginHost + # map :navy => :dark_blue, + # :maroon => :brown, + # :luna => :moon + # end + def map hash + for from, to in hash + from = validate_id from + to = validate_id to + plugin_hash[from] = to unless plugin_hash.has_key? from + end + end + + # Define the default plugin to use when no plugin is found + # for a given id. + # + # See also map. + # + # class MyColorHost < PluginHost + # map :navy => :dark_blue + # default :gray + # end + def default id = nil + if id + id = validate_id id + plugin_hash[nil] = id + else + plugin_hash[nil] + end + end + + # Every plugin must register itself for one or more + # +ids+ by calling register_for, which calls this method. + # + # See Plugin#register_for. + def register plugin, *ids + for id in ids + unless id.is_a? Symbol + raise ArgumentError, + "id must be a Symbol, but it was a #{id.class}" + end + plugin_hash[validate_id(id)] = plugin + end + end + + # A Hash of plugion_id => Plugin pairs. + def plugin_hash + @plugin_hash ||= create_plugin_hash + end + + # Returns an array of all .rb files in the plugin path. + # + # The extension .rb is not included. + def list + Dir[path_to('*')].select do |file| + File.basename(file)[/^(?!_)\w+\.rb$/] + end.map do |file| + File.basename file, '.rb' + end + end + + # Makes a map of all loaded plugins. + def inspect + map = plugin_hash.dup + map.each do |id, plugin| + map[id] = plugin.to_s[/(?>\w+)$/] + end + "#{name}[#{host_id}]#{map.inspect}" + end + +protected + # Created a new plugin list and stores it to @plugin_hash. + def create_plugin_hash + @plugin_hash = + Hash.new do |h, plugin_id| + id = validate_id(plugin_id) + path = path_to id + begin + require path + rescue LoadError => boom + if h.has_key? nil # default plugin + h[id] = h[nil] + else + raise PluginNotFound, 'Could not load plugin %p: %s' % [id, boom] + end + else + # Plugin should have registered by now + unless h.has_key? id + raise PluginNotFound, + "No #{self.name} plugin for #{id.inspect} found in #{path}." + end + end + h[id] + end + end + + # Loads the map file (see map). + # + # This is done automatically when plugin_path is called. + def load_map + mapfile = path_to '_map' + if File.exist? mapfile + require mapfile + elsif $DEBUG + warn 'no _map.rb found for %s' % name + end + end + + # Returns the Plugin for +id+. + # Use it like Hash#fetch. + # + # Example: + # yaml_plugin = MyPluginHost[:yaml, :default] + def fetch id, *args, &blk + plugin_hash.fetch validate_id(id), *args, &blk + end + + # Returns the expected path to the plugin file for the given id. + def path_to plugin_id + File.join plugin_path, "#{plugin_id}.rb" + end + + # Converts +id+ to a Symbol if it is a String, + # or returns +id+ if it already is a Symbol. + # + # Raises +ArgumentError+ for all other objects, or if the + # given String includes non-alphanumeric characters (\W). + def validate_id id + if id.is_a? Symbol or id.nil? + id + elsif id.is_a? String + if id[/\w+/] == id + id.downcase.to_sym + else + raise ArgumentError, "Invalid id: '#{id}' given." + end + else + raise ArgumentError, + "String or Symbol expected, but #{id.class} given." + end + end + +end + + +# = Plugin +# +# Plugins have to include this module. +# +# IMPORTANT: use extend for this module. +# +# Example: see PluginHost. +module Plugin + + def included mod + warn "#{name} should not be included. Use extend." + end + + # Register this class for the given langs. + # Example: + # class MyPlugin < PluginHost::BaseClass + # register_for :my_id + # ... + # end + # + # See PluginHost.register. + def register_for *ids + plugin_host.register self, *ids + end + + def title title = nil + if title + @title = title.to_s + else + @title ||= name[/([^:]+)$/, 1] + end + end + + # The host for this Plugin class. + def plugin_host host = nil + if host and not host.is_a? PluginHost + raise ArgumentError, + "PluginHost expected, but #{host.class} given." + end + self.const_set :PLUGIN_HOST, host if host + self::PLUGIN_HOST + end + + # Require some helper files. + # + # Example: + # + # class MyPlugin < PluginHost::BaseClass + # register_for :my_id + # helper :my_helper + # + # The above example loads the file myplugin/my_helper.rb relative to the + # file in which MyPlugin was defined. + # + # You can also load a helper from a different plugin: + # + # helper 'other_plugin/other_helper' + def helper *helpers + for helper in helpers + if helper.is_a?(String) && helper[/\//] + self::PLUGIN_HOST.require_helper $`, $' + else + self::PLUGIN_HOST.require_helper plugin_id, helper.to_s + end + end + end + + # Returns the pulgin id used by the engine. + def plugin_id + name[/\w+$/].downcase + end + +end + +# Convenience method for plugin loading. +# The syntax used is: +# +# CodeRay.require_plugin '<Host ID>/<Plugin ID>' +# +# Returns the loaded plugin. +def self.require_plugin path + host_id, plugin_id = path.split '/', 2 + host = PluginHost.host_by_id(host_id) + raise PluginHost::HostNotFound, + "No host for #{host_id.inspect} found." unless host + host.load plugin_id +end + +end
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