Rails::Dom::Testing
This gem is responsible for comparing HTML doms and asserting that DOM elements are present in Rails applications.
Doms are compared via assert_dom_equal
and assert_dom_not_equal
.
Elements are asserted via assert_select
, assert_select_encoded
, assert_select_email
and a subset of the dom can be selected with css_select
.
The gem is developed for Rails 4.2 and above, and will not work on previous versions.
Installation
Add this line to your application's Gemfile:
gem 'rails-dom-testing'
And then execute:
$ bundle
Or install it yourself as:
$ gem install rails-dom-testing
Usage
Dom Assertions
assert_dom_equal '<h1>Lingua França</h1>', '<h1>Lingua França</h1>'
assert_dom_not_equal '<h1>Portuguese</h1>', '<h1>Danish</h1>'
Selector Assertions
# implicitly selects from the document_root_element
css_select '.hello' # => Nokogiri::XML::NodeSet of elements with hello class
# select from a supplied node. assert_select asserts elements exist.
assert_select document_root_element.at('.hello'), '.goodbye'
# elements in CDATA encoded sections can also be selected
assert_select_encoded '#out-of-your-element'
# assert elements within an html email exists
assert_select_email '#you-got-mail'
The documentation in selector_assertions.rb goes into a lot more detail of how selector assertions can be used.
Read more
Under the hood the doms are parsed with Nokogiri and you'll generally be working with these two classes:
Read more about Nokogiri:
Contributing
- Fork it
- Create your feature branch (
git checkout -b my-new-feature
) - Commit your changes (
git commit -am 'Add some feature'
) - Push to the branch (
git push origin my-new-feature
) - Create new Pull Request