1 files changed, 48 insertions, 4 deletions
diff --git a/railties/lib/rails/generators/generated_attribute.rb b/railties/lib/rails/generators/generated_attribute.rb
index 816d82cac3..5ba37737a2 100644
--- a/railties/lib/rails/generators/generated_attribute.rb
+++ b/railties/lib/rails/generators/generated_attribute.rb
@@ -4,11 +4,10 @@ require 'active_support/core_ext/object/inclusion'
 module Rails
   module Generators
     class GeneratedAttribute
-      attr_accessor :name, :type
+      attr_accessor :name, :type, :has_index, :attr_options
 
-      def initialize(name, type)
-        type = :string if type.blank?
-        @name, @type = name, type.to_sym
+      def initialize(column_definition)
+        parse column_definition
       end
 
       def field_type
@@ -48,6 +47,51 @@ module Rails
       def reference?
         self.type.in?([:references, :belongs_to])
       end
+      
+      def has_index?
+        @has_index
+      end
+
+      def has_uniq_index?
+        @has_uniq_index
+      end
+
+      def parse(column_definition)
+        name, type, has_index = column_definition.split(':')
+        # if user provided "name:index" instead of "name:string:index" type should be set blank
+        # so GeneratedAttribute's constructor could set it to :string
+        if type =~ /index|uniq|unique/i
+          has_index = type
+          type = nil
+        end
+        type = :string if type.blank?
+
+        @name = name
+        @type, @attr_options = *parse_type_and_options(type)
+        @has_index = ['index','uniq','unique'].include?(has_index)
+        @has_uniq_index = ['uniq','unique'].include?(has_index)
+      end
+
+      # parse possible attribute options like :limit for string/text/binary/integer or :precision/:scale for decimals
+      # when declaring options curly brackets should be used
+      def parse_type_and_options(type)
+        attribute_options = case type 
+          when /(string|text|binary|integer){(\d+)}/
+            {:limit => $2.to_i}
+          when /decimal{(\d+),(\d+)}/
+            {:precision => $1.to_i, :scale => $2.to_i}
+          else; {}
+        end
+        [type.to_s.gsub(/{.*}/,'').to_sym, attribute_options]
+      end
+
+      def inject_options
+        @attr_options.blank? ? '' : ", #{@attr_options.to_s.gsub(/[{}]/, '')}"
+      end
+
+      def inject_index_options
+        has_uniq_index? ? ", :unique => true" : ''
+      end
     end
   end
 end