require "active_support/core_ext/enumerable" module ActionView class ActionViewError < StandardError #:nodoc: end class MissingTemplate < ActionViewError #:nodoc: attr_reader :path def initialize(paths, path, details, partial) @path = path display_paths = paths.compact.map{ |p| p.to_s.inspect }.join(", ") template_type = if partial "partial" elsif path =~ /layouts/i 'layout' else 'template' end super("Missing #{template_type} #{path} with #{details.inspect} in view paths #{display_paths}") end end class Template # The Template::Error exception is raised when the compilation of the template fails. This exception then gathers a # bunch of intimate details and uses it to report a very precise exception message. class Error < ActionViewError #:nodoc: SOURCE_CODE_RADIUS = 3 attr_reader :original_exception def initialize(template, assigns, original_exception) @template, @assigns, @original_exception = template, assigns.dup, original_exception @backtrace = compute_backtrace end def file_name @template.identifier end def message ActiveSupport::Deprecation.silence { original_exception.message } end def clean_backtrace if defined?(Rails) && Rails.respond_to?(:backtrace_cleaner) Rails.backtrace_cleaner.clean(original_exception.backtrace) else original_exception.backtrace end end def sub_template_message if @sub_templates "Trace of template inclusion: " + @sub_templates.collect { |template| template.inspect }.join(", ") else "" end end def source_extract(indentation = 0) return unless num = line_number num = num.to_i source_code = @template.source.split("\n") start_on_line = [ num - SOURCE_CODE_RADIUS - 1, 0 ].max end_on_line = [ num + SOURCE_CODE_RADIUS - 1, source_code.length].min indent = ' ' * indentation line_counter = start_on_line return unless source_code = source_code[start_on_line..end_on_line] source_code.sum do |line| line_counter += 1 "#{indent}#{line_counter}: #{line}\n" end end def sub_template_of(template_path) @sub_templates ||= [] @sub_templates << template_path end def line_number @line_number ||= if file_name regexp = /#{Regexp.escape File.basename(file_name)}:(\d+)/ $1 if message =~ regexp or clean_backtrace.find { |line| line =~ regexp } end end def to_s "\n#{self.class} (#{message}) #{source_location}:\n" + "#{source_extract}\n #{clean_backtrace.join("\n ")}\n\n" end # don't do anything nontrivial here. Any raised exception from here becomes fatal # (and can't be rescued). def backtrace @backtrace end private def compute_backtrace [ "#{source_location.capitalize}\n\n#{source_extract(4)}\n " + clean_backtrace.join("\n ") ] end def source_location if line_number "on line ##{line_number} of " else 'in ' end + file_name end end end TemplateError = Template::Error end