Prefer to instantiate fixtures with model classes instead of their names, avoiding excess constant lookups. Closes #10677 [nwilmes]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@8561 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/lib/active_record/fixtures.rb

@@ -689,7 +689,7 @@ class Fixtures < (RUBY_VERSION < '1.9' ? YAML::Omap : Hash)
         Dir.entries(@fixture_path).each do |file|
           path = File.join(@fixture_path, file)
           if File.file?(path) and file !~ @file_filter
-            self[file] = Fixture.new(path, @class_name)
+            self[file] = Fixture.new(path, model_class)
           end
         end
       end
@@ -718,7 +718,7 @@ class Fixtures < (RUBY_VERSION < '1.9' ? YAML::Omap : Hash)
               raise Fixture::FormatError, "Bad data for #{@class_name} fixture named #{name} (nil)"
             end
 
-            self[name] = Fixture.new(data, @class_name)
+            self[name] = Fixture.new(data, model_class)
           end
         end
       end
@@ -731,7 +731,7 @@ class Fixtures < (RUBY_VERSION < '1.9' ? YAML::Omap : Hash)
       reader.each do |row|
         data = {}
         row.each_with_index { |cell, j| data[header[j].to_s.strip] = cell.to_s.strip }
-        self["#{Inflector::underscore(@class_name)}_#{i+=1}"]= Fixture.new(data, @class_name)
+        self["#{Inflector::underscore(@class_name)}_#{i+=1}"] = Fixture.new(data, model_class)
       end
     end
 
@@ -767,9 +767,9 @@ class Fixture #:nodoc:
   class FormatError < FixtureError #:nodoc:
   end
 
-  attr_reader :class_name
+  attr_reader :model_class
 
-  def initialize(fixture, class_name)
+  def initialize(fixture, model_class)
     case fixture
       when Hash, YAML::Omap
         @fixture = fixture
@@ -779,7 +779,11 @@ class Fixture #:nodoc:
         raise ArgumentError, "Bad fixture argument #{fixture.inspect} during creation of #{class_name} fixture"
     end
 
-    @class_name = class_name
+    @model_class = model_class.is_a?(Class) ? model_class : model_class.constantize rescue nil
+  end
+
+  def class_name
+    @model_class.name if @model_class
   end
 
   def each
@@ -800,21 +804,18 @@ class Fixture #:nodoc:
   end
 
   def value_list
-    klass = @class_name.constantize rescue nil
-
     list = @fixture.inject([]) do |fixtures, (key, value)|
-      col = klass.columns_hash[key] if klass.respond_to?(:ancestors) && klass.ancestors.include?(ActiveRecord::Base)
+      col = model_class.columns_hash[key] if model_class.respond_to?(:ancestors) && model_class.ancestors.include?(ActiveRecord::Base)
       fixtures << ActiveRecord::Base.connection.quote(value, col).gsub('[^\]\\n', "\n").gsub('[^\]\\r', "\r")
     end
     list * ', '
   end
 
   def find
-    klass = @class_name.is_a?(Class) ? @class_name : Object.const_get(@class_name) rescue nil
-    if klass
-      klass.find(self[klass.primary_key])
+    if model_class
+      model_class.find(self[model_class.primary_key])
     else
-      raise FixtureClassNotFound, "The class #{@class_name.inspect} was not found."
+      raise FixtureClassNotFound, "No class attached to find."
     end
   end