require 'action_dispatch/http/mime_type'
require 'active_support/core_ext/class/attribute'
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
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)
if template.source.encoding_aware?
# 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!
else
erb = template.source.dup
end
self.class.erb_implementation.new(
erb,
:escape => (self.class.escape_whitelist.include? template.mime_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