Froze rails gems

[depot.git] / vendor / rails / activesupport / lib / active_support / core_ext / module / aliasing.rb

diff --git a/vendor/rails/activesupport/lib/active_support/core_ext/module/aliasing.rb b/vendor/rails/activesupport/lib/active_support/core_ext/module/aliasing.rb
new file mode 100644 (file)
index 0000000..e640f64
--- /dev/null
+++ b/vendor/rails/activesupport/lib/active_support/core_ext/module/aliasing.rb
@@ -0,0 +1,74 @@
+module ActiveSupport
+  module CoreExtensions
+    module Module
+      # Encapsulates the common pattern of:
+      #
+      #   alias_method :foo_without_feature, :foo
+      #   alias_method :foo, :foo_with_feature
+      #
+      # With this, you simply do:
+      #
+      #   alias_method_chain :foo, :feature
+      #
+      # And both aliases are set up for you.
+      #
+      # Query and bang methods (foo?, foo!) keep the same punctuation:
+      #
+      #   alias_method_chain :foo?, :feature
+      #
+      # is equivalent to
+      #
+      #   alias_method :foo_without_feature?, :foo?
+      #   alias_method :foo?, :foo_with_feature?
+      #
+      # so you can safely chain foo, foo?, and foo! with the same feature.
+      def alias_method_chain(target, feature)
+        # Strip out punctuation on predicates or bang methods since
+        # e.g. target?_without_feature is not a valid method name.
+        aliased_target, punctuation = target.to_s.sub(/([?!=])$/, ''), $1
+        yield(aliased_target, punctuation) if block_given?
+
+        with_method, without_method = "#{aliased_target}_with_#{feature}#{punctuation}", "#{aliased_target}_without_#{feature}#{punctuation}"
+
+        alias_method without_method, target
+        alias_method target, with_method
+
+        case
+          when public_method_defined?(without_method)
+            public target
+          when protected_method_defined?(without_method)
+            protected target
+          when private_method_defined?(without_method)
+            private target
+        end
+      end
+
+      # Allows you to make aliases for attributes, which includes
+      # getter, setter, and query methods.
+      #
+      # Example:
+      #
+      #   class Content < ActiveRecord::Base
+      #     # has a title attribute
+      #   end
+      #
+      #   class Email < Content
+      #     alias_attribute :subject, :title
+      #   end
+      #
+      #   e = Email.find(1)
+      #   e.title    # => "Superstars"
+      #   e.subject  # => "Superstars"
+      #   e.subject? # => true
+      #   e.subject = "Megastars"
+      #   e.title    # => "Megastars"
+      def alias_attribute(new_name, old_name)
+        module_eval <<-STR, __FILE__, __LINE__+1
+          def #{new_name}; self.#{old_name}; end
+          def #{new_name}?; self.#{old_name}?; end
+          def #{new_name}=(v); self.#{old_name} = v; end
+        STR
+      end
+    end
+  end
+end