Added the command plugin

5 files changed, 98 insertions, 10 deletions

diff --git a/lib/bundler/cli.rb b/lib/bundler/cli.rb
index 75d4581e12..7cde242804 100644
--- a/lib/bundler/cli.rb
+++ b/lib/bundler/cli.rb
@@ -82,6 +82,10 @@ module Bundler
     end
 
     def self.handle_no_command_error(command, has_namespace = $thor_runner)
+      if Bundler::Plugin.command? command
+        return Bundler::Plugin.exec_command(command, ARGV[1..-1])
+      end
+
       return super unless command_path = Bundler.which("bundler-#{command}")
 
       Kernel.exec(command_path, *ARGV[1..-1])
diff --git a/lib/bundler/cli/install.rb b/lib/bundler/cli/install.rb
index efde762e5a..0589b87d26 100644
--- a/lib/bundler/cli/install.rb
+++ b/lib/bundler/cli/install.rb
@@ -96,7 +96,7 @@ module Bundler
       # rubygems plugins sometimes hook into the gem install process
       Gem.load_env_plugins if Gem.respond_to?(:load_env_plugins)
 
-      Bundler::Plugin.eval_gemfile(Bundler.default_gemfile)
+      Plugin.eval_gemfile(Bundler.default_gemfile)
 
       definition = Bundler.definition
       definition.validate_ruby!
diff --git a/lib/bundler/plugin.rb b/lib/bundler/plugin.rb
index e4ab928735..4bf398e0eb 100644
--- a/lib/bundler/plugin.rb
+++ b/lib/bundler/plugin.rb
@@ -2,11 +2,16 @@
 
 module Bundler
   class Plugin
+    autoload :Api,        "bundler/plugin/api"
     autoload :Dsl,        "bundler/plugin/dsl"
     autoload :Index,      "bundler/plugin/index"
     autoload :Installer,  "bundler/plugin/installer"
     autoload :SourceList, "bundler/plugin/source_list"
 
+    PLUGIN_FILE_NAME = "plugin.rb".freeze
+
+    @commands = {}
+
     class << self
       # Installs a new plugin by the given name
       #
@@ -60,6 +65,22 @@ module Bundler
         @cache ||= root.join("cache")
       end
 
+      def add_command(command, cls)
+        @commands[command] = cls
+      end
+
+      def command?(command)
+        index.command? command
+      end
+
+      def exec_command(command, args)
+        raise "Command #{command} not found" unless command? command
+
+        load_plugin index.command_plugin(command) unless @commands.key? command
+
+        @commands[command].new.exec(command, args)
+      end
+
     private
 
       # Checks if the gem is good to be a plugin
@@ -70,8 +91,8 @@ module Bundler
       #
       # @raise [Error] if plugin.rb file is not found
       def validate_plugin!(plugin_path)
-        plugin_file = plugin_path.join("plugin.rb")
-        raise "plugin.rb was not found in the plugin!" unless plugin_file.file?
+        plugin_file = plugin_path.join(PLUGIN_FILE_NAME)
+        raise "#{PLUGIN_FILE_NAME} was not found in the plugin!" unless plugin_file.file?
       end
 
       # Runs the plugin.rb file, records the plugin actions it registers for and
@@ -80,9 +101,21 @@ module Bundler
       # @param [String] name the name of the plugin
       # @param [Pathname] path the path where the plugin is installed at
       def register_plugin(name, path)
-        require path.join("plugin.rb") # this shall latter be used to find the actions the plugin performs
+        commands = @commands
+
+        @commands = {}
+
+        require path.join(PLUGIN_FILE_NAME) # this shall latter be used to find the actions the plugin performs
+
+        index.register_plugin name, path.to_s, @commands.keys
+      ensure
+        @commands = commands
+      end
+
+      def load_plugin(name)
+        path = index.plugin_path(name)
 
-        index.register_plugin name, path.to_s
+        load path.join(PLUGIN_FILE_NAME)
       end
     end
   end
diff --git a/lib/bundler/plugin/api.rb b/lib/bundler/plugin/api.rb
new file mode 100644
index 0000000000..267b448cc3
--- /dev/null
+++ b/lib/bundler/plugin/api.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+module Bundler
+  # This is the interfacing class represents the API that we intend to provide
+  # the plugins to use.
+  #
+  # For plugins to be independent of the Bundler internals they shall limit their
+  # interactions to methods of this class only. This will save them from breaking
+  # when some internal change.
+  class Plugin::Api
+    def self.command(command)
+      Plugin.add_command command, self
+    end
+
+    # The cache dir to be used by the plugins for persistance storage
+    #
+    # @return [Pathname] path of the cache dir
+    def cache
+      Plugin.cache.join("plugins")
+    end
+
+    # A tmp dir to be used by plugins
+    # Note: Its desirable to explicitly remove the dir after use
+    #
+    # @param [String] name unique for the plugin or the purpose
+    # @return [Pathname] object for the new directory created
+    def tmp(name)
+      Bundler.tmp(File.join(["plugin", name]))
+    end
+  end
+end
diff --git a/lib/bundler/plugin/index.rb b/lib/bundler/plugin/index.rb
index 0fc70af27a..5d8e896f30 100644
--- a/lib/bundler/plugin/index.rb
+++ b/lib/bundler/plugin/index.rb
@@ -7,7 +7,8 @@ module Bundler
   # now a stub class).
   class Plugin::Index
     def initialize
-      @plugin_sources = {}
+      @plugin_paths = {}
+      @commands = {}
 
       load_index
     end
@@ -17,8 +18,13 @@ module Bundler
     #
     # @param [String] name of the plugin to be registered
     # @param [String] path where the plugin is installed
-    def register_plugin(name, path)
-      @plugin_sources[name] = path
+    # @param [Array<String>] commands that are handled by the plugin
+    def register_plugin(name, path, commands)
+      @plugin_paths[name] = path
+
+      common = commands & @commands.keys
+      raise "Command(s) #{common.join(", ")} are already registered" if common.any?
+      commands.each{|c| @commands[c] = name }
 
       save_index
     end
@@ -28,6 +34,18 @@ module Bundler
       Plugin.root.join("index")
     end
 
+    def plugin_path(name)
+      Pathname.new @plugin_paths[name]
+    end
+
+    def command?(command)
+      @commands.key? command
+    end
+
+    def command_plugin(command)
+      @commands[command]
+    end
+
   private
 
     # Reads the index file from the directory and initializes the instance variables.
@@ -36,7 +54,8 @@ module Bundler
         valid_file = index_f && index_f.exist? && !index_f.size.zero?
         break unless valid_file
         index = YAML.load_file(index_f)
-        @plugin_sources = index["plugin_sources"]
+        @plugin_paths = index["plugin_paths"]
+        @commands = index["commands"]
       end
     end
 
@@ -44,7 +63,8 @@ module Bundler
     # variables in YAML format. (The instance variables are supposed to be only String key value pairs)
     def save_index
       index = {
-        "plugin_sources" => @plugin_sources,
+        "plugin_paths" => @plugin_paths,
+        "commands" => @commands,
       }
 
       SharedHelpers.filesystem_access(index_file) do |index_f|