Using JSErrorCollector w/ Ruby + Watir

jserrorcollector.rb

require 'watir-webdriver'

profile = Selenium::WebDriver::Firefox::Profile.new
profile.add_extension File.join(Rails.root, "/JSErrorCollector.xpi")
                
browser = Watir::Browser.new :firefox, :profile => profile
browser.goto 'www.google.com'

errors = browser.execute_script("return window.JSErrorCollector_errors.pump()")
             
if errors.any?
	puts "-------------------------------------------------------------"
	puts "Found #{errors.length} javascript error(s)"
	puts "-------------------------------------------------------------"

	errors.each do |error|
		puts error["errorMessage"] + " (" + error["sourceName"] + ":" + error["lineNumber"] + ")"
	end

	@file.close
end