cheat sheets.

== assert_have_selector

# Matches HTML content against a CSS 3 selector.
# In Webrat core, Webrat Selenium

assert_have_selector    'div.pagination'
assert_have_no_selector 'form input#name'

assert_have_selector 'img',  :src     => image_url
assert_have_selector '.cpm', :content => "$100.00"
assert_have_selector 'li',   :count   => 2