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Diffstat (limited to 'actionpack/lib/action_dispatch/testing/assertions/selector.rb')
| -rw-r--r-- | actionpack/lib/action_dispatch/testing/assertions/selector.rb | 430 |
1 files changed, 430 insertions, 0 deletions
diff --git a/actionpack/lib/action_dispatch/testing/assertions/selector.rb b/actionpack/lib/action_dispatch/testing/assertions/selector.rb new file mode 100644 index 0000000000..12023e6f77 --- /dev/null +++ b/actionpack/lib/action_dispatch/testing/assertions/selector.rb @@ -0,0 +1,430 @@ +require 'action_view/vendor/html-scanner' +require 'active_support/core_ext/object/inclusion' + +#-- +# Copyright (c) 2006 Assaf Arkin (http://labnotes.org) +# Under MIT and/or CC By license. +#++ + +module ActionDispatch + 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. + # + # Also see HTML::Selector to learn how to use selectors. + 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 array + # if no match is found. + # + # If called with two arguments, uses the first argument as the base + # element and the second argument as the selector. Attempts to match the + # base element and any of its children. Returns an empty array if no + # match is found. + # + # The selector may be a CSS selector expression (String), an expression + # with substitution values (Array) or an HTML::Selector object. + # + # # 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) + # See assert_select to understand what's going on here. + arg = args.shift + + if arg.is_a?(HTML::Node) + root = arg + arg = args.shift + elsif arg == 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 defined?(@selected) && @selected + matches = [] + + @selected.each do |selected| + subset = css_select(selected, HTML::Selector.new(arg.dup, args.dup)) + subset.each do |match| + matches << match unless matches.any? { |m| m.equal?(match) } + end + end + + return matches + else + root = response_from_page + end + + case arg + when String + selector = HTML::Selector.new(arg, args) + when Array + selector = HTML::Selector.new(*arg) + when HTML::Selector + selector = arg + else raise ArgumentError, "Expecting a selector as the first argument" + end + + selector.select(root) + 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 if 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), an expression + # with substitution values, or an HTML::Selector object. + # + # === 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#?", /item-\d+/ + # + # # All input fields in the form have a name + # assert_select "form input" do + # assert_select "[name=?]", /.+/ # Not empty + # end + def assert_select(*args, &block) + # Start with optional element followed by mandatory selector. + arg = args.shift + @selected ||= nil + + if arg.is_a?(HTML::Node) + # First argument is a node (tag or text, but also HTML root), + # so we know what we're selecting from. + root = arg + arg = args.shift + elsif arg == nil + # This usually happens when passing a node/element that + # happens to be 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 @selected + root = HTML::Node.new(nil) + root.children.concat @selected + else + # Otherwise just operate on the response document. + root = response_from_page + end + + # First or second argument is the selector: string and we pass + # all remaining arguments. Array and we pass the argument. Also + # accepts selector itself. + case arg + when String + selector = HTML::Selector.new(arg, args) + when Array + selector = HTML::Selector.new(*arg) + when HTML::Selector + selector = arg + else raise ArgumentError, "Expecting a selector as the first argument" + end + + # Next argument is used for equality tests. + equals = {} + case arg = args.shift + when Hash + equals = arg + when String, Regexp + equals[:text] = arg + when Integer + equals[:count] = arg + when Range + equals[:minimum] = arg.begin + equals[:maximum] = arg.end + when FalseClass + equals[:count] = 0 + when NilClass, TrueClass + equals[: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 equals[:count] + equals[:minimum] = equals[:maximum] = equals[:count] + else + equals[:minimum] = 1 unless equals[:minimum] + end + + # Last argument is the message we use if the assertion fails. + message = args.shift + #- message = "No match made with selector #{selector.inspect}" unless message + if args.shift + raise ArgumentError, "Not expecting that last argument, you either have too many arguments, or they're the wrong type" + end + + matches = selector.select(root) + # If text/html, narrow down to those elements that match it. + content_mismatch = nil + if match_with = equals[:text] + matches.delete_if do |match| + text = "" + stack = match.children.reverse + while node = stack.pop + if node.tag? + stack.concat node.children.reverse + else + content = node.content + text << content + end + end + text.strip! unless NO_STRIP.include?(match.name) + text.sub!(/\A\n/, '') if match.name == "textarea" + unless match_with.is_a?(Regexp) ? (text =~ match_with) : (text == match_with.to_s) + content_mismatch ||= sprintf("<%s> expected but was\n<%s>", match_with, text) + true + end + end + elsif match_with = equals[:html] + matches.delete_if do |match| + html = match.children.map(&:to_s).join + html.strip! unless NO_STRIP.include?(match.name) + unless match_with.is_a?(Regexp) ? (html =~ match_with) : (html == match_with.to_s) + content_mismatch ||= sprintf("<%s> expected but was\n<%s>", match_with, html) + true + end + end + end + # Expecting foo found bar element only if found zero, not if + # found one but expecting two. + message ||= content_mismatch if matches.empty? + # Test minimum/maximum occurrence. + min, max, count = equals[:minimum], equals[:maximum], equals[:count] + + # FIXME: minitest provides messaging when we use assert_operator, + # so is this custom message really needed? + message = message || %(Expected #{count_description(min, max, count)} matching "#{selector.to_s}", found #{matches.size}) + if count + assert_equal count, matches.size, message + else + assert_operator matches.size, :>=, min, message if min + assert_operator matches.size, :<=, max, message if max + end + + # If a block is given call that block. Set @selected to allow + # nested assert_select, which 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 + + # Returns all matches elements. + 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 HTML::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 + + fix_content = lambda do |node| + # Gets around a bug in the Rails 1.1 HTML parser. + node.content.gsub(/<!\[CDATA\[(.*)(\]\]>)?/m) { Rack::Utils.escapeHTML($1) } + end + + selected = elements.map do |elem| + text = elem.children.select{ |c| not c.tag? }.map{ |c| fix_content[c] }.join + root = HTML::Document.new(CGI.unescapeHTML("<encoded>#{text}</encoded>")).root + css_select(root, "encoded:root", &block)[0] + end + + begin + old_selected, @selected = @selected, selected + assert_select ":root", &block + 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 = HTML::Document.new(part.body.to_s).root + assert_select root, ":root", &block + end + end + end + end + + protected + # +assert_select+ and +css_select+ call this to obtain the content in the HTML page. + def response_from_page + html_document.root + end + end + end +end |