Moved encoding work in progress to a feature branch.

This reverts commits af0d1a88157942c6e6398dbf73891cff1e152405 and 64d109e3539ad600f58536d3ecabd2f87b67fd1c.

1 files changed, 25 insertions, 170 deletions

diff --git a/actionpack/lib/action_view/template.rb b/actionpack/lib/action_view/template.rb
index 5d8ac6b115..a1a970e2d2 100644
--- a/actionpack/lib/action_view/template.rb
+++ b/actionpack/lib/action_view/template.rb
@@ -1,89 +1,12 @@
+# encoding: utf-8
+# This is so that templates compiled in this file are UTF-8
 require 'active_support/core_ext/array/wrap'
 require 'active_support/core_ext/object/blank'
-require 'active_support/core_ext/kernel/singleton_class'
 
 module ActionView
   class Template
     extend ActiveSupport::Autoload
 
-    # === Encodings in ActionView::Template
-    #
-    # ActionView::Template is one of a few sources of potential
-    # encoding issues in Rails. This is because the source for
-    # templates are usually read from disk, and Ruby (like most
-    # encoding-aware programming languages) assumes that the
-    # String retrieved through File IO is encoded in the
-    # <tt>default_external</tt> encoding. In Rails, the default
-    # <tt>default_external</tt> encoding is UTF-8.
-    #
-    # As a result, if a user saves their template as ISO-8859-1
-    # (for instance, using a non-Unicode-aware text editor),
-    # and uses characters outside of the ASCII range, their
-    # users will see diamonds with question marks in them in
-    # the browser.
-    #
-    # To mitigate this problem, we use a few strategies:
-    # 1. If the source is not valid UTF-8, we raise an exception
-    #    when the template is compiled to alert the user
-    #    to the problem.
-    # 2. The user can specify the encoding using Ruby-style
-    #    encoding comments in any template engine. If such
-    #    a comment is supplied, Rails will apply that encoding
-    #    to the resulting compiled source returned by the
-    #    template handler.
-    # 3. In all cases, we transcode the resulting String to
-    #    the <tt>default_internal</tt> encoding (which defaults
-    #    to UTF-8).
-    #
-    # This means that other parts of Rails can always assume
-    # that templates are encoded in UTF-8, even if the original
-    # source of the template was not UTF-8.
-    #
-    # From a user's perspective, the easiest thing to do is
-    # to save your templates as UTF-8. If you do this, you
-    # do not need to do anything else for things to "just work".
-    #
-    # === Instructions for template handlers
-    #
-    # The easiest thing for you to do is to simply ignore
-    # encodings. Rails will hand you the template source
-    # as the default_internal (generally UTF-8), raising
-    # an exception for the user before sending the template
-    # to you if it could not determine the original encoding.
-    #
-    # For the greatest simplicity, you can support only
-    # UTF-8 as the <tt>default_internal</tt>. This means
-    # that from the perspective of your handler, the
-    # entire pipeline is just UTF-8.
-    #
-    # === Advanced: Handlers with alternate metadata sources
-    #
-    # If you want to provide an alternate mechanism for
-    # specifying encodings (like ERB does via <%# encoding: ... %>),
-    # you may indicate that you are willing to accept
-    # BINARY data by implementing <tt>self.accepts_binary?</tt>
-    # on your handler.
-    #
-    # If you do, Rails will not raise an exception if
-    # the template's encoding could not be determined,
-    # assuming that you have another mechanism for
-    # making the determination.
-    #
-    # In this case, make sure you return a String from
-    # your handler encoded in the default_internal. Since
-    # you are handling out-of-band metadata, you are
-    # also responsible for alerting the user to any
-    # problems with converting the user's data to
-    # the default_internal.
-    #
-    # To do so, simply raise the raise WrongEncodingError
-    # as follows:
-    #
-    #     raise WrongEncodingError.new(
-    #       problematic_string,
-    #       expected_encoding
-    #     )
-
     eager_autoload do
       autoload :Error
       autoload :Handler
@@ -93,22 +16,20 @@ module ActionView
 
     extend Template::Handlers
 
-    attr_reader :source, :identifier, :handler, :virtual_path, :formats,
-                :original_encoding
+    attr_reader :source, :identifier, :handler, :virtual_path, :formats
 
-    Finalizer = proc do |method_name, mod|
+    Finalizer = proc do |method_name|
       proc do
-        mod.module_eval do
+        ActionView::CompiledTemplates.module_eval do
           remove_possible_method method_name
         end
       end
     end
 
     def initialize(source, identifier, handler, details)
-      @source             = source
-      @identifier         = identifier
-      @handler            = handler
-      @original_encoding  = nil
+      @source     = source
+      @identifier = identifier
+      @handler    = handler
 
       @virtual_path = details[:virtual_path]
       @method_names = {}
@@ -121,13 +42,7 @@ module ActionView
       # Notice that we use a bang in this instrumentation because you don't want to
       # consume this in production. This is only slow if it's being listened to.
       ActiveSupport::Notifications.instrument("!render_template.action_view", :virtual_path => @virtual_path) do
-        if view.is_a?(ActionView::CompiledTemplates)
-          mod = ActionView::CompiledTemplates
-        else
-          mod = view.singleton_class
-        end
-
-        method_name = compile(locals, view, mod)
+        method_name = compile(locals, view)
         view.send(method_name, locals, &block)
       end
     rescue Exception => e
@@ -135,7 +50,7 @@ module ActionView
         e.sub_template_of(self)
         raise e
       else
-        raise Template::Error.new(self, view.respond_to?(:assigns) ? view.assigns : {}, e)
+        raise Template::Error.new(self, view.assigns, e)
       end
     end
 
@@ -160,97 +75,37 @@ module ActionView
     end
 
     private
-      # Among other things, this method is responsible for properly setting
-      # the encoding of the source. Until this point, we assume that the
-      # source is BINARY data. If no additional information is supplied,
-      # we assume the encoding is the same as Encoding.default_external.
-      #
-      # The user can also specify the encoding via a comment on the first
-      # line of the template (# encoding: NAME-OF-ENCODING). This will work
-      # with any template engine, as we process out the encoding comment
-      # before passing the source on to the template engine, leaving a
-      # blank line in its stead.
-      #
-      # Note that after we figure out the correct encoding, we then
-      # encode the source into Encoding.default_internal. In general,
-      # this means that templates will be UTF-8 inside of Rails,
-      # regardless of the original source encoding.
-      def compile(locals, view, mod)
+      def compile(locals, view)
         method_name = build_method_name(locals)
         return method_name if view.respond_to?(method_name)
 
         locals_code = locals.keys.map! { |key| "#{key} = local_assigns[:#{key}];" }.join
 
-        if source.encoding_aware?
-          if source.sub!(/\A#{ENCODING_FLAG}/, '')
-            encoding = $1
-          else
-            encoding = Encoding.default_external
-          end
-
-          # Tag the source with the default external encoding
-          # or the encoding specified in the file
-          source.force_encoding(encoding)
-
-          # If the original encoding is BINARY, the actual
-          # encoding is either stored out-of-band (such as
-          # in ERB <%# %> style magic comments) or missing.
-          # This is also true if the original encoding is
-          # something other than BINARY, but it's invalid.
-          if source.encoding != Encoding::BINARY && source.valid_encoding?
-            source.encode!
-          # If the assumed encoding is incorrect, check to
-          # see whether the handler accepts BINARY. If it
-          # does, it has another mechanism for determining
-          # the true encoding of the String.
-          elsif @handler.respond_to?(:accepts_binary?) && @handler.accepts_binary?
-            source.force_encoding(Encoding::BINARY)
-          # If the handler does not accept BINARY, the
-          # assumed encoding (either the default_external,
-          # or the explicit encoding specified by the user)
-          # is incorrect. We raise an exception here.
-          else
-            raise WrongEncodingError.new(source, encoding)
-          end
-
-          # Don't validate the encoding yet -- the handler
-          # may treat the String as raw bytes and extract
-          # the encoding some other way
-        end
-
         code = @handler.call(self)
+        if code.sub!(/\A(#.*coding.*)\n/, '')
+          encoding_comment = $1
+        elsif defined?(Encoding) && Encoding.respond_to?(:default_external)
+          encoding_comment = "#coding:#{Encoding.default_external}"
+        end
 
         source = <<-end_src
           def #{method_name}(local_assigns)
-            _old_virtual_path, @_virtual_path = @_virtual_path, #{@virtual_path.inspect};_old_output_buffer = @output_buffer;#{locals_code};#{code}
+            _old_virtual_path, @_virtual_path = @_virtual_path, #{@virtual_path.inspect};_old_output_buffer = output_buffer;#{locals_code};#{code}
           ensure
-            @_virtual_path, @output_buffer = _old_virtual_path, _old_output_buffer
+            @_virtual_path, self.output_buffer = _old_virtual_path, _old_output_buffer
           end
         end_src
 
-        if source.encoding_aware?
-          # Handlers should return their source Strings in either the
-          # default_internal or BINARY. If the handler returns a BINARY
-          # String, we assume its encoding is the one we determined
-          # earlier, and encode the resulting source in the default_internal.
-          if source.encoding == Encoding::BINARY
-            source.force_encoding(Encoding.default_internal)
-          end
-
-          # In case we get back a String from a handler that is not in
-          # BINARY or the default_internal, encode it to the default_internal
-          source.encode!
-
-          # Now, validate that the source we got back from the template
-          # handler is valid in the default_internal
-          unless source.valid_encoding?
-            raise WrongEncodingError.new(@source, Encoding.default_internal)
-          end
+        if encoding_comment
+          source = "#{encoding_comment}\n#{source}"
+          line = -1
+        else
+          line = 0
         end
 
         begin
-          mod.module_eval(source, identifier, 0)
-          ObjectSpace.define_finalizer(self, Finalizer[method_name, mod])
+          ActionView::CompiledTemplates.module_eval(source, identifier, line)
+          ObjectSpace.define_finalizer(self, Finalizer[method_name])
 
           method_name
         rescue Exception => e # errors from template code