module ActionView
module Assertions
NO_STRIP = %w{pre script style textarea}
# 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
# to match all elements of the current page. 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).
#
# # 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 ? response_from_page : args.shift
selector = args.first
root.css(selector).tap do |matches|
if matches.empty? && root.matches?(selector)
return Nokogiri::XML::NodeSet.new(root.document, [root])
end
end
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, calling +assert_select+ selects from the
# response HTML unless +assert_select+ is called from within an +assert_select+ block.
#
# 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 "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(@selected, response_from_page, args)
matches = selector.select
assert_size_match!(matches.size, selector.equality_tests, selector.source, selector.message)
# Set @selected to allow nested assert_select.
# Can be nested several levels deep.
if block_given? && !matches.empty?
begin
in_scope, @selected = @selected, matches
yield matches
ensure
@selected = in_scope
end
end
matches
end
def count_description(min, max, count) #:nodoc:
pluralize = lambda {|word, quantity| word << (quantity == 1 ? '' : 's')}
if min && max && (max != min)
"between #{min} and #{max} elements"
elsif min && max && max == min && count
"exactly #{count} #{pluralize['element', min]}"
elsif min && !(min == 1 && max == 1)
"at least #{min} #{pluralize['element', min]}"
elsif max
"at most #{max} #{pluralize['element', max]}"
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)
case element
when Array
elements = element
when Nokogiri::XML::Node
elements = [element]
when nil
unless elements = @selected
raise ArgumentError, "First argument is optional, but must be called from a nested assert_select"
end
else
raise ArgumentError, "Argument is optional, and may be node or array of nodes"
end
content = elements.map do |elem|
elem.children.select(&:cdata?).map(&:content)
end.join
selected = Loofah.fragment(content)
begin
old_selected, @selected = @selected, selected
if content.empty?
yield selected
else
assert_select ":root", &block
end
ensure
@selected = old_selected
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 = Loofah.fragment(part.body.to_s)
assert_select root, ":root", &block
end
end
end
end
protected
# +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 size, count, message
else
assert_operator size, :>=, min, message if min
assert_operator size, :<=, max, message if max
end
end
# +html_document+ is used in testing/integration.rb
def html_document
@html_document ||= if @response.content_type =~ /xml$/
Loofah.xml_document(@response.body)
else
Loofah.document(@response.body)
end
end
def response_from_page
html_document.root
end
class HTMLSelector #:nodoc:
attr_accessor :root, :css_selector, :equality_tests, :message
alias :source :css_selector
def initialize(selected, page, args)
# Start with optional element followed by mandatory selector.
@root = determine_root_from(args.first, page, selected)
# First or second argument is the selector
selector = @css_selector_is_second_argument ? args.shift(2).last : args.shift
@css_selector = selector_from(selector, args)
@equality_tests = equality_tests_from(args.shift)
@message = args.shift
if args.shift
raise ArgumentError, "Not expecting that last argument, you either have too many arguments, or they're the wrong type"
end
end
def select
filter root.css(css_selector, context)
end
def filter(matches)
match_with = equality_tests[:text] || equality_tests[:html]
return matches if matches.empty? || !match_with
content_mismatch = nil
text_matches = equality_tests.has_key?(:text)
remaining = matches.reject do |match|
# Preserve markup with to_s for html elements
content = text_matches ? match.text : match.children.to_s
content.strip! unless NO_STRIP.include?(match.name)
content.sub!(/\A\n/, '') if text_matches && match.name == "textarea"
unless match_with.is_a?(Regexp) ? (content =~ match_with) : (content == match_with.to_s)
content_mismatch ||= sprintf("<%s> expected but was\n<%s>.", match_with, content)
true
end
end
# Expecting foo found bar element only if found zero, not if
# found one but expecting two.
self.message ||= content_mismatch if remaining.empty?
Nokogiri::XML::NodeSet.new(matches.document, remaining)
end
def determine_root_from(root_or_selector, page, previous_selection = nil)
@css_selector_is_second_argument = false
if root_or_selector == nil
raise ArgumentError, "First argument is either selector or element to select, but nil found. Perhaps you called assert_select with an element that does not exist?"
elsif root_or_selector.is_a?(Nokogiri::XML::Node) || root_or_selector.is_a?(Nokogiri::XML::NodeSet)
# First argument is a node (tag or text, but also HTML root),
# so we know what we're selecting from.
@css_selector_is_second_argument = true
root_or_selector
elsif previous_selection
if previous_selection.is_a?(Array)
Nokogiri::XML::NodeSet.new(previous_selection[0].document, previous_selection)
else
previous_selection
end
else
page
end
end
def selector_from(selector, substitution_values)
unless selector.is_a? String
raise ArgumentError, "Expecting a selector as the first argument"
end
context.substitute!(selector, substitution_values)
end
def equality_tests_from(comparator)
comparisons = {}
case comparator
when Hash
comparisons = comparator
when String, Regexp
comparisons[:text] = comparator
when Integer
comparisons[:count] = comparator
when Range
comparisons[:minimum] = comparator.begin
comparisons[:maximum] = comparator.end
when FalseClass
comparisons[:count] = 0
when NilClass, TrueClass
comparisons[:minimum] = 1
else raise ArgumentError, "I don't understand what you're trying to match"
end
# By default we're looking for at least one match.
if comparisons[:count]
comparisons[:minimum] = comparisons[:maximum] = comparisons[:count]
else
comparisons[:minimum] ||= 1
end
comparisons
end
def context
@context ||= SubstitutionContext.new
end
class SubstitutionContext
def initialize(substitute = '?')
@substitute = substitute
@regexes = []
end
def add_regex(regex)
# Nokogiri doesn't like arbitrary values without quotes, hence inspect.
return regex.inspect unless regex.is_a?(Regexp)
@regexes.push(regex)
last_id.to_s # avoid implicit conversions of Fixnum to String
end
def last_id
@regexes.count - 1
end
def match(matches, attribute, id)
matches.find_all { |node| node[attribute] =~ @regexes[id] }
end
def substitute!(selector, values)
while !values.empty? && selector.index(@substitute)
selector.sub!(@substitute, add_regex(values.shift))
end
selector
end
end
end
end
end
end
