add readme and tests

README

@@ -0,0 +1,31 @@
+= finder
+
+http://github.com/rubysolo/finder
+
+== DESCRIPTION:
+
+finder is a super light rails plugin that adds hash-style lookups to ActiveRecord models
+
+== EXAMPLE:
+
+Given the following class definition:
+
+  class State < ActiveRecord::Base
+    finder :abbreviation
+  end
+
+You can look up states via their abbreviations like so:
+
+  @colorado = State[:co]
+
+This is roughly equivalent to the following implementation:
+
+  class State < ActiveRecord::Base
+    validates_uniqueness_of :abbreviation
+
+    def self.[](state_code)
+      find_by_abbreviation(state_code)
+    end
+  end
+
+...except it adds ActiveSupport caching for speedy lookups.

init.rb

@@ -1,4 +1,4 @@
 require 'finder'
 ActiveRecord::Base.class_eval do
-  include ActiveRecord::Finder
+  include Rubysolo::Finder
 end

lib/finder.rb

@@ -1,4 +1,7 @@
-module ActiveRecord # :nodoc:
+require 'activesupport' unless defined? ActiveSupport
+require 'activerecord' unless defined? ActiveRecord
+
+module Rubysolo # :nodoc:
   module Finder
     def self.included(base) # :nodoc:
       base.extend ClassMethods
@@ -11,16 +14,18 @@ class << self
         end
         self.finder_attribute = attr_name
 
-        self.send(:include, Finder)
+        self.send(:include, FindableModel)
         (class << self; self; end).module_eval do
           alias_method "for_#{attr_name}".to_sym, :[]
         end
       end
     end
 
-    module Finder
+    module FindableModel
       def self.included(base)
         base.instance_eval do
+          validates_uniqueness_of finder_attribute
+
           cattr_accessor :cache_store
           self.cache_store = ActiveSupport::Cache::MemoryStore.new
 
@@ -29,6 +34,10 @@ def self.[](token)
           end
         end
       end
+
+      def is?(token)
+        self[self.class.finder_attribute] == token.to_s
+      end
     end
   end
 end