Moved Dom and Selector assertions from ActionDispatch to ActionView.

4 files changed, 549 insertions, 0 deletions

diff --git a/actionview/lib/action_view/test_case.rb b/actionview/lib/action_view/test_case.rb
index 112923adf9..7415bfd684 100644
--- a/actionview/lib/action_view/test_case.rb
+++ b/actionview/lib/action_view/test_case.rb
@@ -34,6 +34,7 @@ module ActionView
       extend ActiveSupport::Concern
 
       include ActionDispatch::Assertions, ActionDispatch::TestProcess
+      include ActionView::Assertions
       include ActionController::TemplateAssertions
       include ActionView::Context
 
diff --git a/actionview/lib/action_view/testing/assertions.rb b/actionview/lib/action_view/testing/assertions.rb
new file mode 100644
index 0000000000..9714d3510d
--- /dev/null
+++ b/actionview/lib/action_view/testing/assertions.rb
@@ -0,0 +1,11 @@
+module ActionView
+  module Assertions
+    autoload :DomAssertions, 'action_view/testing/assertions/dom'
+    autoload :SelectorAssertions, 'action_view/testing/assertions/selector'
+
+    extend ActiveSupport::Concern
+
+    include DomAssertions
+    include SelectorAssertions
+  end
+end
\ No newline at end of file
diff --git a/actionview/lib/action_view/testing/assertions/dom.rb b/actionview/lib/action_view/testing/assertions/dom.rb
new file mode 100644
index 0000000000..56edf48770
--- /dev/null
+++ b/actionview/lib/action_view/testing/assertions/dom.rb
@@ -0,0 +1,72 @@
+module ActionView
+  module Assertions
+    module DomAssertions
+      # \Test two HTML strings for equivalency (e.g., equal even when attributes are in another order)
+      #
+      #   # assert that the referenced method generates the appropriate HTML string
+      #   assert_dom_equal '<a href="http://www.example.com">Apples</a>', link_to("Apples", "http://www.example.com")
+      def assert_dom_equal(expected, actual, message = nil)
+        expected_dom, actual_dom = doms_from_strings(expected, actual)
+        message ||= "Expected: #{expected_dom}\nActual: #{actual_dom}"
+        assert compare_doms(expected_dom, actual_dom), message
+      end
+
+      # The negated form of +assert_dom_equal+.
+      #
+      #   # assert that the referenced method does not generate the specified HTML string
+      #   assert_dom_not_equal '<a href="http://www.example.com">Apples</a>', link_to("Oranges", "http://www.example.com")
+      def assert_dom_not_equal(expected, actual, message = nil)
+        expected_dom, actual_dom = doms_from_strings(expected, actual)
+        message ||= "Expected: #{expected_dom}\nActual: #{actual_dom}"
+        assert_not compare_doms(expected_dom, actual_dom), message
+      end
+
+      protected
+        # +doms_from_strings+ creates a Loofah::HTML::DocumentFragment for every string in strings
+        def doms_from_strings(*strings)
+          strings.map { |str| Loofah.fragment(str) }
+        end
+
+        # +compare_doms+ takes two doms loops over all their children and compares each child via +equal_children?+
+        def compare_doms(expected, actual)
+          expected.children.each_with_index do |child, i|
+            return false unless equal_children?(child, actual.children[i])
+          end
+          true
+        end
+
+        # +equal_children?+ compares children according to their type
+        # Determines further comparison via said type
+        # i.e. element node children with equal names has their attributes compared using +attributes_are_equal?+
+        def equal_children?(child, other_child)
+          return false unless child.type == other_child.type
+
+          case child.type
+          when Nokogiri::XML::Node::ELEMENT_NODE
+            child.name == other_child.name && attributes_are_equal?(child, other_child)
+          else
+            child.to_s == other_child.to_s
+          end
+        end
+
+        # +attributes_are_equal?+ sorts elements attributes by name and compares
+        # each attribute by calling +equal_attribute?+
+        # If those are +true+ the attributes are considered equal
+        def attributes_are_equal?(element, other_element)
+          first_nodes = element.attribute_nodes.sort_by { |a| a.name }
+          other_nodes = other_element.attribute_nodes.sort_by { |a| a.name }
+
+          return false unless first_nodes.size == other_nodes.size
+          first_nodes.each_with_index do |attr, i|
+            return false unless equal_attribute?(attr, other_nodes[i])
+          end
+          true
+        end
+
+        # +equal_attribute?+ compares attributes by their name and value
+        def equal_attribute?(attr, other_attr)
+          attr.name == other_attr.name && attr.value == other_attr.value
+        end
+    end
+  end
+end
diff --git a/actionview/lib/action_view/testing/assertions/selector.rb b/actionview/lib/action_view/testing/assertions/selector.rb
new file mode 100644
index 0000000000..bc8f40a245
--- /dev/null
+++ b/actionview/lib/action_view/testing/assertions/selector.rb
@@ -0,0 +1,465 @@
+require 'active_support/core_ext/object/inclusion'
+
+#--
+# Copyright (c) 2006 Assaf Arkin (http://labnotes.org)
+# Under MIT and/or CC By license.
+#++
+
+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" if args.empty?
+
+        if args.first.is_a?(String)
+          root, selector = response_from_page, args.first
+        else
+          root, selector = args.shift, args.first
+        end
+
+        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.comparisons, 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, :comparisons, :message
+
+          alias :source :css_selector
+
+          def initialize(selected, page, args)
+            @selected, @page = selected, page
+
+            # Start with optional element followed by mandatory selector.
+            @root = determine_root_from(args.first)
+
+            # 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)
+
+            # Next argument is used for equality tests.
+            @comparisons = comparisons_from(args.shift)
+
+            # Last argument is the message we use if the assertion fails.
+            @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 = comparisons[:text] || comparisons[:html]
+            return matches if matches.empty? || !match_with
+
+            content_mismatch = nil
+            text_matches = comparisons.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)
+            @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 @selected
+              if @selected.is_a?(Array)
+                doc = @selected.empty? ? @page.document : @selected[0].document
+                @selected = Nokogiri::XML::NodeSet.new(doc, @selected)
+              end
+              @selected
+            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 comparisons_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