Ensure ERB source begins with the encoding comment

2 files changed, 8 insertions, 2 deletions

diff --git a/actionpack/lib/action_view/template/handlers/erb.rb b/actionpack/lib/action_view/template/handlers/erb.rb
index d773df7d29..21272ef089 100644
--- a/actionpack/lib/action_view/template/handlers/erb.rb
+++ b/actionpack/lib/action_view/template/handlers/erb.rb
@@ -16,7 +16,9 @@ module ActionView
       self.default_format = Mime::HTML
 
       def compile(template)
-        ::ERB.new("<% __in_erb_template=true %>#{template.source}", nil, erb_trim_mode, '@output_buffer').src
+        magic = $1 if template.source =~ /\A(<%#.*coding:\s*(\S+)\s*-?%>)/
+        erb = "#{magic}<% __in_erb_template=true %>#{template.source}"
+        ::ERB.new(erb, nil, erb_trim_mode, '@output_buffer').src
       end
     end
   end
diff --git a/actionpack/lib/action_view/template/template.rb b/actionpack/lib/action_view/template/template.rb
index a9897258d2..e7ea42c2eb 100644
--- a/actionpack/lib/action_view/template/template.rb
+++ b/actionpack/lib/action_view/template/template.rb
@@ -53,7 +53,11 @@ module ActionView
       locals_code = locals.keys.map! { |key| "#{key} = local_assigns[:#{key}];" }.join
 
       code = @handler.call(self)
-      encoding_comment = $1 if code.sub!(/\A(#.*coding.*)\n/, '')
+      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)