Set headers capybara / mechanize

gistfile1.rb

#env.rb
begin require 'rspec/expectations'; rescue LoadError; require 'spec/expectations'; end
require 'capybara'
require 'capybara/dsl'
require 'capybara/cucumber'
require 'selenium-webdriver'
require 'capybara/mechanize/cucumber'

World do
  Capybara.default_driver = :mechanize
  Capybara.javascript_driver = :selenium
  Capybara.app_host = 'http://example.com'
  Capybara
end

# step definition
When /^I visit some URL$/ do
  headers = {
    'foo' => 'bar'
  }
  @agent = Mechanize.new
  @page = @agent.get('http://example.com', [], nil, headers)
end

Then /^I something should have happened$/ do
  @page.body.should have_some_thing
end