Make Storage a subclass of BaseStorage which supports per-instance

storage_dir.

plugins/core/lib/core/plugin/storage.rb

@@ -1,23 +1,18 @@
 
 module Redcar
   class Plugin
-    class Storage
-      class << self
-        attr_writer :storage_dir
-      end
-
-      def self.storage_dir
-        @user_dir ||= File.join(Redcar.user_dir, "storage")
-      end
-
+    class BaseStorage
+
       # Open a storage file or create it if it doesn't exist.
       #
+      # @param [String] storage_dir  the path to the directory the storage file should exist in
       # @param [String] name  a (short) name, should be suitable for use as a filename
-      def initialize(name)
+      def initialize(storage_dir, name)
+        @storage_dir = storage_dir
         @name  = name
         @mutex = Mutex.new
-        unless File.exists?(Storage.storage_dir)
-          FileUtils.mkdir_p(Storage.storage_dir)
+        unless File.exists?(@storage_dir)
+          FileUtils.mkdir_p(@storage_dir)
         end
         rollback
       end
@@ -82,14 +77,28 @@ def keys
       private
 
       def path
-        File.join(Storage.storage_dir, @name + ".yaml")
+        File.join(@storage_dir, @name + ".yaml")
       end
 
       def update_timestamp
         @last_modified_time = File.stat(path).mtime
       end
     end
 
+    class Storage < Plugin::BaseStorage
+      class << self
+        attr_writer :storage_dir
+      end
+
+      def self.storage_dir
+        @user_dir ||= File.join(Redcar.user_dir, "storage")
+      end
+
+      def initialize(name)
+        super(self.class.storage_dir, name)
+      end
+    end
+
     # A Storage which is used by multiple plugins. This kind of storage can only
     # contain arrays, because otherwise plugins could not set their defaults as
     # addition to the existing ones of other plugins.