require 'action_dispatch/http/mime_type' require 'erubis' module ActionView class Template module Handlers class Erubis < ::Erubis::Eruby def add_preamble(src) src << "@output_buffer = output_buffer || ActionView::OutputBuffer.new;" end def add_text(src, text) return if text.empty? src << "@output_buffer.safe_concat('" << escape_text(text) << "');" end # Erubis toggles <%= and <%== behavior when escaping is enabled. # We override to always treat <%== as escaped. def add_expr(src, code, indicator) case indicator when '==' add_expr_escaped(src, code) else super end end BLOCK_EXPR = /\s+(do|\{)(\s*\|[^|]*\|)?\s*\Z/ def add_expr_literal(src, code) if code =~ BLOCK_EXPR src << '@output_buffer.append= ' << code else src << '@output_buffer.append= (' << code << ');' end end def add_expr_escaped(src, code) if code =~ BLOCK_EXPR src << "@output_buffer.safe_append= " << code else src << "@output_buffer.safe_concat((" << code << ").to_s);" end end def add_postamble(src) src << '@output_buffer.to_s' end end class ERB # Specify trim mode for the ERB compiler. Defaults to '-'. # See ERB documentation for suitable values. class_attribute :erb_trim_mode self.erb_trim_mode = '-' # Default implementation used. class_attribute :erb_implementation self.erb_implementation = Erubis # Do not escape templates of these mime types. class_attribute :escape_whitelist self.escape_whitelist = ["text/plain"] ENCODING_TAG = Regexp.new("\\A(<%#{ENCODING_FLAG}-?%>)[ \\t]*") def self.call(template) new.call(template) end def supports_streaming? true end def handles_encoding? true end def call(template) # First, convert to BINARY, so in case the encoding is # wrong, we can still find an encoding tag # (<%# encoding %>) inside the String using a regular # expression template_source = template.source.dup.force_encoding("BINARY") erb = template_source.gsub(ENCODING_TAG, '') encoding = $2 erb.force_encoding valid_encoding(template.source.dup, encoding) # Always make sure we return a String in the default_internal erb.encode! self.class.erb_implementation.new( erb, :escape => (self.class.escape_whitelist.include? template.type), :trim => (self.class.erb_trim_mode == "-") ).src end private def valid_encoding(string, encoding) # If a magic encoding comment was found, tag the # String with this encoding. This is for a case # where the original String was assumed to be, # for instance, UTF-8, but a magic comment # proved otherwise string.force_encoding(encoding) if encoding # If the String is valid, return the encoding we found return string.encoding if string.valid_encoding? # Otherwise, raise an exception raise WrongEncodingError.new(string, string.encoding) end end end end end