Remove support for taint checking

lib/liquid/errors.rb

@@ -46,7 +46,6 @@ module Liquid
   StandardError       = Class.new(Error)
   SyntaxError         = Class.new(Error)
   StackLevelError     = Class.new(Error)
-  TaintedError        = Class.new(Error)
   MemoryError         = Class.new(Error)
   ZeroDivisionError   = Class.new(Error)
   FloatDomainError    = Class.new(Error)

lib/liquid/standardfilters.rb

@@ -41,7 +41,7 @@ module Liquid
     end
 
     def escape(input)
-      CGI.escapeHTML(input.to_s).untaint unless input.nil?
+      CGI.escapeHTML(input.to_s) unless input.nil?
     end
     alias_method :h, :escape
 

lib/liquid/template.rb

@@ -64,23 +64,6 @@ module Liquid
       attr_accessor :error_mode
       Template.error_mode = :lax
 
-      attr_reader :taint_mode
-
-      # Sets how strict the taint checker should be.
-      # :lax is the default, and ignores the taint flag completely
-      # :warn adds a warning, but does not interrupt the rendering
-      # :error raises an error when tainted output is used
-      # @deprecated Since it is being deprecated in ruby itself.
-      def taint_mode=(mode)
-        taint_supported = Object.new.taint.tainted?
-        if mode != :lax && !taint_supported
-          raise NotImplementedError, "#{RUBY_ENGINE} #{RUBY_VERSION} doesn't support taint checking"
-        end
-        @taint_mode = mode
-      end
-
-      Template.taint_mode = :lax
-
       attr_accessor :default_exception_renderer
       Template.default_exception_renderer = lambda do |exception|
         exception

lib/liquid/variable.rb

@@ -86,9 +86,7 @@ module Liquid
         context.invoke(filter_name, output, *filter_args)
       end
 
-      obj = context.apply_global_filter(obj)
-      taint_check(context, obj)
-      obj
+      context.apply_global_filter(obj)
     end
 
     def render_to_output_buffer(context, output)
@@ -142,25 +140,6 @@ module Liquid
       parsed_args
     end
 
-    def taint_check(context, obj)
-      return if Template.taint_mode == :lax
-      return unless obj.tainted?
-
-      @markup =~ QuotedFragment
-      name = Regexp.last_match(0)
-
-      error               = TaintedError.new("variable '#{name}' is tainted and was not escaped")
-      error.line_number   = line_number
-      error.template_name = context.template_name
-
-      case Template.taint_mode
-      when :warn
-        context.warnings << error
-      when :error
-        raise error
-      end
-    end
-
     class ParseTreeVisitor < Liquid::ParseTreeVisitor
       def children
         [@node.name] + @node.filters.flatten