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.

Nokogiri::CSS::SyntaxError exceptions when upgrading to Rails 4.2:

Nokogiri is slightly stricter about the format of CSS selectors than the previous implementation.

Check the 4.2 release notes section on assert_select for help.

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

“by assert_dom_equal ‘

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’, ‘

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assert_dom_not_equal ‘

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’, ‘

Danish

Selector Assertions

“by

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: - Nokogiri::XML::Node - Nokogiri::XML::NodeSet

Read more about Nokogiri: - Nokogiri

Contributing to Rails::Dom::Testing

Rails::Dom::Testing is work of many contributors. You’re encouraged to submit pull requests, propose features and discuss issues.

See CONTRIBUTING.

License

Rails::Dom::Testing is released under the MIT License.