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require 'active_support/deprecation'
require_relative 'selector_assertions/count_describable'
require_relative 'selector_assertions/html_selector'
module Rails
module Dom
module Testing
module Assertions
# Adds the +assert_select+ method for use in Rails functional
# test cases, which can be used to make assertions on the response HTML of a controller
# action. You can also call +assert_select+ within another +assert_select+ to
# make assertions on elements selected by the enclosing assertion.
#
# Use +css_select+ to select elements without making an assertions, either
# from the response HTML or elements selected by the enclosing assertion.
#
# In addition to HTML responses, you can make the following assertions:
#
# * +assert_select_encoded+ - Assertions on HTML encoded inside XML, for example for dealing with feed item descriptions.
# * +assert_select_email+ - Assertions on the HTML body of an e-mail.
module SelectorAssertions
# Select and return all matching elements.
#
# If called with a single argument, uses that argument as a selector.
# Called without an element +css_select+ selects from
# the element returned in +document_root_element+
#
# The default implementation of +document_root_element+ raises an exception explaining this.
#
# Returns an empty Nokogiri::XML::NodeSet if no match is found.
#
# If called with two arguments, uses the first argument as the root
# element and the second argument as the selector. Attempts to match the
# root element and any of its children.
# Returns an empty Nokogiri::XML::NodeSet if no match is found.
#
# The selector may be a CSS selector expression (String).
# css_select returns nil if called with an invalid css selector.
#
# # Selects all div tags
# divs = css_select("div")
#
# # Selects all paragraph tags and does something interesting
# pars = css_select("p")
# pars.each do |par|
# # Do something fun with paragraphs here...
# end
#
# # Selects all list items in unordered lists
# items = css_select("ul>li")
#
# # Selects all form tags and then all inputs inside the form
# forms = css_select("form")
# forms.each do |form|
# inputs = css_select(form, "input")
# ...
# end
def css_select(*args)
raise ArgumentError, "you at least need a selector argument" if args.empty?
root = args.size == 1 ? document_root_element : args.shift
nodeset(root).css(args.first)
end
# An assertion that selects elements and makes one or more equality tests.
#
# If the first argument is an element, selects all matching elements
# starting from (and including) that element and all its children in
# depth-first order.
#
# If no element is specified +assert_select+ selects from
# the element returned in +document_root_element+
# unless +assert_select+ is called from within an +assert_select+ block.
# Override +document_root_element+ to tell +assert_select+ what to select from.
# The default implementation raises an exception explaining this.
#
# When called with a block +assert_select+ passes an array of selected elements
# to the block. Calling +assert_select+ from the block, with no element specified,
# runs the assertion on the complete set of elements selected by the enclosing assertion.
# Alternatively the array may be iterated through so that +assert_select+ can be called
# separately for each element.
#
#
# ==== Example
# If the response contains two ordered lists, each with four list elements then:
# assert_select "ol" do |elements|
# elements.each do |element|
# assert_select element, "li", 4
# end
# end
#
# will pass, as will:
# assert_select "ol" do
# assert_select "li", 8
# end
#
# The selector may be a CSS selector expression (String) or an expression
# with substitution values (Array).
# Substitution uses a custom pseudo class match. Pass in whatever attribute you want to match (enclosed in quotes) and a ? for the substitution.
# assert_select returns nil if called with an invalid css selector.
#
# assert_select "div:match('id', ?)", /\d+/
#
# === Equality Tests
#
# The equality test may be one of the following:
# * <tt>true</tt> - Assertion is true if at least one element selected.
# * <tt>false</tt> - Assertion is true if no element selected.
# * <tt>String/Regexp</tt> - Assertion is true if the text value of at least
# one element matches the string or regular expression.
# * <tt>Integer</tt> - Assertion is true if exactly that number of
# elements are selected.
# * <tt>Range</tt> - Assertion is true if the number of selected
# elements fit the range.
# If no equality test specified, the assertion is true if at least one
# element selected.
#
# To perform more than one equality tests, use a hash with the following keys:
# * <tt>:text</tt> - Narrow the selection to elements that have this text
# value (string or regexp).
# * <tt>:html</tt> - Narrow the selection to elements that have this HTML
# content (string or regexp).
# * <tt>:count</tt> - Assertion is true if the number of selected elements
# is equal to this value.
# * <tt>:minimum</tt> - Assertion is true if the number of selected
# elements is at least this value.
# * <tt>:maximum</tt> - Assertion is true if the number of selected
# elements is at most this value.
#
# If the method is called with a block, once all equality tests are
# evaluated the block is called with an array of all matched elements.
#
# # At least one form element
# assert_select "form"
#
# # Form element includes four input fields
# assert_select "form input", 4
#
# # Page title is "Welcome"
# assert_select "title", "Welcome"
#
# # Page title is "Welcome" and there is only one title element
# assert_select "title", {count: 1, text: "Welcome"},
# "Wrong title or more than one title element"
#
# # Page contains no forms
# assert_select "form", false, "This page must contain no forms"
#
# # Test the content and style
# assert_select "body div.header ul.menu"
#
# # Use substitution values
# assert_select "ol>li:match('id', ?)", /item-\d+/
#
# # All input fields in the form have a name
# assert_select "form input" do
# assert_select ":match('name', ?)", /.+/ # Not empty
# end
def assert_select(*args, &block)
@selected ||= nil
selector = HTMLSelector.new(args, @selected) { nodeset document_root_element }
if selector.selecting_no_body?
assert true
return
end
selector.select.tap do |matches|
assert_size_match!(matches.size, selector.tests,
selector.css_selector, selector.message)
nest_selection(matches, &block) if block_given? && !matches.empty?
end
end
# Extracts the content of an element, treats it as encoded HTML and runs
# nested assertion on it.
#
# You typically call this method within another assertion to operate on
# all currently selected elements. You can also pass an element or array
# of elements.
#
# The content of each element is un-encoded, and wrapped in the root
# element +encoded+. It then calls the block with all un-encoded elements.
#
# # Selects all bold tags from within the title of an Atom feed's entries (perhaps to nab a section name prefix)
# assert_select "feed[xmlns='http://www.w3.org/2005/Atom']" do
# # Select each entry item and then the title item
# assert_select "entry>title" do
# # Run assertions on the encoded title elements
# assert_select_encoded do
# assert_select "b"
# end
# end
# end
#
#
# # Selects all paragraph tags from within the description of an RSS feed
# assert_select "rss[version=2.0]" do
# # Select description element of each feed item.
# assert_select "channel>item>description" do
# # Run assertions on the encoded elements.
# assert_select_encoded do
# assert_select "p"
# end
# end
# end
def assert_select_encoded(element = nil, &block)
if !element && !@selected
raise ArgumentError, "Element is required when called from a nonnested assert_select"
end
content = nodeset(element || @selected).map do |elem|
elem.children.select do |child|
child.cdata? || (child.text? && !child.blank?)
end.map(&:content)
end.join
selected = Nokogiri::HTML::DocumentFragment.parse(content)
nest_selection(selected) do
if content.empty?
yield selected
else
assert_select ":root", &block
end
end
end
# Extracts the body of an email and runs nested assertions on it.
#
# You must enable deliveries for this assertion to work, use:
# ActionMailer::Base.perform_deliveries = true
#
# assert_select_email do
# assert_select "h1", "Email alert"
# end
#
# assert_select_email do
# items = assert_select "ol>li"
# items.each do
# # Work with items here...
# end
# end
def assert_select_email(&block)
deliveries = ActionMailer::Base.deliveries
assert !deliveries.empty?, "No e-mail in delivery list"
deliveries.each do |delivery|
(delivery.parts.empty? ? [delivery] : delivery.parts).each do |part|
if part["Content-Type"].to_s =~ /^text\/html\W/
root = Nokogiri::HTML::DocumentFragment.parse(part.body.to_s)
assert_select root, ":root", &block
end
end
end
end
private
include CountDescribable
def document_root_element
raise NotImplementedError, 'Implementing document_root_element makes ' \
'assert_select work without needing to specify an element to select from.'
end
# +equals+ must contain :minimum, :maximum and :count keys
def assert_size_match!(size, equals, css_selector, message = nil)
min, max, count = equals[:minimum], equals[:maximum], equals[:count]
message ||= %(Expected #{count_description(min, max, count)} matching "#{css_selector}", found #{size}.)
if count
assert_equal count, size, message
else
assert_operator size, :>=, min, message if min
assert_operator size, :<=, max, message if max
end
end
def nest_selection(selection)
# Set @selected to allow nested assert_select.
# Can be nested several levels deep.
old_selected, @selected = @selected, selection
yield @selected
ensure
@selected = old_selected
end
def nodeset(node)
if node.is_a?(Nokogiri::XML::NodeSet)
node
else
Nokogiri::XML::NodeSet.new(node.document, [node])
end
end
end
end
end
end
end