Standardise the implementation of the extensions to BigDecimal. Closes #10608 [mikong]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@9091 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/lib/active_support/core_ext/bigdecimal.rb

 require 'bigdecimal'
 require 'active_support/core_ext/bigdecimal/conversions'
+
+class BigDecimal#:nodoc:
+  include ActiveSupport::CoreExtensions::BigDecimal::Conversions
+end

activesupport/lib/active_support/core_ext/bigdecimal/conversions.rb

 require 'yaml'
 
-class BigDecimal #:nodoc:
-  alias :_original_to_s :to_s
-  def to_s(format="F")
-    _original_to_s(format)
-  end
-
-  yaml_as "tag:yaml.org,2002:float"
-  def to_yaml( opts = {} )
-    YAML::quick_emit( nil, opts ) do |out|
-      # This emits the number without any scientific notation.
-      # I prefer it to using self.to_f.to_s, which would lose precision.
-      #
-      # Note that YAML allows that when reconsituting floats
-      # to native types, some precision may get lost.
-      # There is no full precision real YAML tag that I am aware of.
-      str = self.to_s
-      if str == "Infinity"
-        str = ".Inf"
-      elsif str == "-Infinity"
-        str = "-.Inf"
-      elsif str == "NaN"
-        str = ".NaN"
+module ActiveSupport #:nodoc:
+  module CoreExtensions #:nodoc:
+    module BigDecimal #:nodoc:
+      module Conversions
+        def self.included(base) #:nodoc:
+          base.instance_eval do
+            alias_method :_original_to_s, :to_s
+            alias_method :to_s, :to_formatted_s
+          end
+        end
+        
+        def to_formatted_s(format="F")
+          _original_to_s(format)
+        end
+        
+        yaml_as "tag:yaml.org,2002:float"
+        def to_yaml( opts = {} )
+          YAML::quick_emit( nil, opts ) do |out|
+            # This emits the number without any scientific notation.
+            # I prefer it to using self.to_f.to_s, which would lose precision.
+            #
+            # Note that YAML allows that when reconsituting floats
+            # to native types, some precision may get lost.
+            # There is no full precision real YAML tag that I am aware of.
+            str = self.to_s
+            if str == "Infinity"
+              str = ".Inf"
+            elsif str == "-Infinity"
+              str = "-.Inf"
+            elsif str == "NaN"
+              str = ".NaN"
+            end
+            out.scalar( "tag:yaml.org,2002:float", str, :plain )
+          end
+        end
       end
-      out.scalar( "tag:yaml.org,2002:float", str, :plain )
     end
   end
 end