vendor/rails/actionpack/lib/action_controller/assertions/selector_assertions.rb

   1 #--
   2 # Copyright (c) 2006 Assaf Arkin (http://labnotes.org)
   3 # Under MIT and/or CC By license.
   4 #++
   5
   6 require 'rexml/document'
   7 require 'html/document'
   8
   9 module ActionController
  10   module Assertions
  11     unless const_defined?(:NO_STRIP)
  12       NO_STRIP = %w{pre script style textarea}
  13     end
  14
  15     # Adds the +assert_select+ method for use in Rails functional
  16     # test cases, which can be used to make assertions on the response HTML of a controller
  17     # action. You can also call +assert_select+ within another +assert_select+ to
  18     # make assertions on elements selected by the enclosing assertion.
  19     #
  20     # Use +css_select+ to select elements without making an assertions, either
  21     # from the response HTML or elements selected by the enclosing assertion.
  22     #
  23     # In addition to HTML responses, you can make the following assertions:
  24     # * +assert_select_rjs+ - Assertions on HTML content of RJS update and insertion operations.
  25     # * +assert_select_encoded+ - Assertions on HTML encoded inside XML, for example for dealing with feed item descriptions.
  26     # * +assert_select_email+ - Assertions on the HTML body of an e-mail.
  27     #
  28     # Also see HTML::Selector to learn how to use selectors.
  29     module SelectorAssertions
  30       # :call-seq:
  31       #   css_select(selector) => array
  32       #   css_select(element, selector) => array
  33       #
  34       # Select and return all matching elements.
  35       #
  36       # If called with a single argument, uses that argument as a selector
  37       # to match all elements of the current page. Returns an empty array
  38       # if no match is found.
  39       #
  40       # If called with two arguments, uses the first argument as the base
  41       # element and the second argument as the selector. Attempts to match the
  42       # base element and any of its children. Returns an empty array if no
  43       # match is found.
  44       #
  45       # The selector may be a CSS selector expression (String), an expression
  46       # with substitution values (Array) or an HTML::Selector object.
  47       #
  48       # ==== Examples
  49       #   # Selects all div tags
  50       #   divs = css_select("div")
  51       #
  52       #   # Selects all paragraph tags and does something interesting
  53       #   pars = css_select("p")
  54       #   pars.each do |par|
  55       #     # Do something fun with paragraphs here...
  56       #   end
  57       #
  58       #   # Selects all list items in unordered lists
  59       #   items = css_select("ul>li")
  60       #
  61       #   # Selects all form tags and then all inputs inside the form
  62       #   forms = css_select("form")
  63       #   forms.each do |form|
  64       #     inputs = css_select(form, "input")
  65       #     ...
  66       #   end
  67       #
  68       def css_select(*args)
  69         # See assert_select to understand what's going on here.
  70         arg = args.shift
  71
  72         if arg.is_a?(HTML::Node)
  73           root = arg
  74           arg = args.shift
  75         elsif arg == nil
  76           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?"
  77         elsif @selected
  78           matches = []
  79
  80           @selected.each do |selected|
  81             subset = css_select(selected, HTML::Selector.new(arg.dup, args.dup))
  82             subset.each do |match|
  83               matches << match unless matches.any? { |m| m.equal?(match) }
  84             end
  85           end
  86
  87           return matches
  88         else
  89           root = response_from_page_or_rjs
  90         end
  91
  92         case arg
  93           when String
  94             selector = HTML::Selector.new(arg, args)
  95           when Array
  96             selector = HTML::Selector.new(*arg)
  97           when HTML::Selector
  98             selector = arg
  99           else raise ArgumentError, "Expecting a selector as the first argument"
 100         end
 101
 102         selector.select(root)
 103       end
 104
 105       # :call-seq:
 106       #   assert_select(selector, equality?, message?)
 107       #   assert_select(element, selector, equality?, message?)
 108       #
 109       # An assertion that selects elements and makes one or more equality tests.
 110       #
 111       # If the first argument is an element, selects all matching elements
 112       # starting from (and including) that element and all its children in
 113       # depth-first order.
 114       #
 115       # If no element if specified, calling +assert_select+ will select from the
 116       # response HTML. Calling #assert_select inside an +assert_select+ block will
 117       # run the assertion for each element selected by the enclosing assertion.
 118       #
 119       # ==== Example
 120       #   assert_select "ol>li" do |elements|
 121       #     elements.each do |element|
 122       #       assert_select element, "li"
 123       #     end
 124       #   end
 125       #
 126       # Or for short:
 127       #   assert_select "ol>li" do
 128       #     assert_select "li"
 129       #   end
 130       #
 131       # The selector may be a CSS selector expression (String), an expression
 132       # with substitution values, or an HTML::Selector object.
 133       #
 134       # === Equality Tests
 135       #
 136       # The equality test may be one of the following:
 137       # * <tt>true</tt> - Assertion is true if at least one element selected.
 138       # * <tt>false</tt> - Assertion is true if no element selected.
 139       # * <tt>String/Regexp</tt> - Assertion is true if the text value of at least
 140       #   one element matches the string or regular expression.
 141       # * <tt>Integer</tt> - Assertion is true if exactly that number of
 142       #   elements are selected.
 143       # * <tt>Range</tt> - Assertion is true if the number of selected
 144       #   elements fit the range.
 145       # If no equality test specified, the assertion is true if at least one
 146       # element selected.
 147       #
 148       # To perform more than one equality tests, use a hash with the following keys:
 149       # * <tt>:text</tt> - Narrow the selection to elements that have this text
 150       #   value (string or regexp).
 151       # * <tt>:html</tt> - Narrow the selection to elements that have this HTML
 152       #   content (string or regexp).
 153       # * <tt>:count</tt> - Assertion is true if the number of selected elements
 154       #   is equal to this value.
 155       # * <tt>:minimum</tt> - Assertion is true if the number of selected
 156       #   elements is at least this value.
 157       # * <tt>:maximum</tt> - Assertion is true if the number of selected
 158       #   elements is at most this value.
 159       #
 160       # If the method is called with a block, once all equality tests are
 161       # evaluated the block is called with an array of all matched elements.
 162       #
 163       # ==== Examples
 164       #
 165       #   # At least one form element
 166       #   assert_select "form"
 167       #
 168       #   # Form element includes four input fields
 169       #   assert_select "form input", 4
 170       #
 171       #   # Page title is "Welcome"
 172       #   assert_select "title", "Welcome"
 173       #
 174       #   # Page title is "Welcome" and there is only one title element
 175       #   assert_select "title", {:count=>1, :text=>"Welcome"},
 176       #       "Wrong title or more than one title element"
 177       #
 178       #   # Page contains no forms
 179       #   assert_select "form", false, "This page must contain no forms"
 180       #
 181       #   # Test the content and style
 182       #   assert_select "body div.header ul.menu"
 183       #
 184       #   # Use substitution values
 185       #   assert_select "ol>li#?", /item-\d+/
 186       #
 187       #   # All input fields in the form have a name
 188       #   assert_select "form input" do
 189       #     assert_select "[name=?]", /.+/  # Not empty
 190       #   end
 191       def assert_select(*args, &block)
 192         # Start with optional element followed by mandatory selector.
 193         arg = args.shift
 194
 195         if arg.is_a?(HTML::Node)
 196           # First argument is a node (tag or text, but also HTML root),
 197           # so we know what we're selecting from.
 198           root = arg
 199           arg = args.shift
 200         elsif arg == nil
 201           # This usually happens when passing a node/element that
 202           # happens to be nil.
 203           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?"
 204         elsif @selected
 205           root = HTML::Node.new(nil)
 206           root.children.concat @selected
 207         else
 208           # Otherwise just operate on the response document.
 209           root = response_from_page_or_rjs
 210         end
 211
 212         # First or second argument is the selector: string and we pass
 213         # all remaining arguments. Array and we pass the argument. Also
 214         # accepts selector itself.
 215         case arg
 216           when String
 217             selector = HTML::Selector.new(arg, args)
 218           when Array
 219             selector = HTML::Selector.new(*arg)
 220           when HTML::Selector
 221             selector = arg
 222           else raise ArgumentError, "Expecting a selector as the first argument"
 223         end
 224
 225         # Next argument is used for equality tests.
 226         equals = {}
 227         case arg = args.shift
 228           when Hash
 229             equals = arg
 230           when String, Regexp
 231             equals[:text] = arg
 232           when Integer
 233             equals[:count] = arg
 234           when Range
 235             equals[:minimum] = arg.begin
 236             equals[:maximum] = arg.end
 237           when FalseClass
 238             equals[:count] = 0
 239           when NilClass, TrueClass
 240             equals[:minimum] = 1
 241           else raise ArgumentError, "I don't understand what you're trying to match"
 242         end
 243
 244         # By default we're looking for at least one match.
 245         if equals[:count]
 246           equals[:minimum] = equals[:maximum] = equals[:count]
 247         else
 248           equals[:minimum] = 1 unless equals[:minimum]
 249         end
 250
 251         # Last argument is the message we use if the assertion fails.
 252         message = args.shift
 253         #- message = "No match made with selector #{selector.inspect}" unless message
 254         if args.shift
 255           raise ArgumentError, "Not expecting that last argument, you either have too many arguments, or they're the wrong type"
 256         end
 257
 258         matches = selector.select(root)
 259         # If text/html, narrow down to those elements that match it.
 260         content_mismatch = nil
 261         if match_with = equals[:text]
 262           matches.delete_if do |match|
 263             text = ""
 264             text.force_encoding(match_with.encoding) if text.respond_to?(:force_encoding)
 265             stack = match.children.reverse
 266             while node = stack.pop
 267               if node.tag?
 268                 stack.concat node.children.reverse
 269               else
 270                 content = node.content
 271                 content.force_encoding(match_with.encoding) if content.respond_to?(:force_encoding)
 272                 text << content
 273               end
 274             end
 275             text.strip! unless NO_STRIP.include?(match.name)
 276             unless match_with.is_a?(Regexp) ? (text =~ match_with) : (text == match_with.to_s)
 277               content_mismatch ||= build_message(message, "<?> expected but was\n<?>.", match_with, text)
 278               true
 279             end
 280           end
 281         elsif match_with = equals[:html]
 282           matches.delete_if do |match|
 283             html = match.children.map(&:to_s).join
 284             html.strip! unless NO_STRIP.include?(match.name)
 285             unless match_with.is_a?(Regexp) ? (html =~ match_with) : (html == match_with.to_s)
 286               content_mismatch ||= build_message(message, "<?> expected but was\n<?>.", match_with, html)
 287               true
 288             end
 289           end
 290         end
 291         # Expecting foo found bar element only if found zero, not if
 292         # found one but expecting two.
 293         message ||= content_mismatch if matches.empty?
 294         # Test minimum/maximum occurrence.
 295         min, max = equals[:minimum], equals[:maximum]
 296         message = message || %(Expected #{count_description(min, max)} matching "#{selector.to_s}", found #{matches.size}.)
 297         assert matches.size >= min, message if min
 298         assert matches.size <= max, message if max
 299
 300         # If a block is given call that block. Set @selected to allow
 301         # nested assert_select, which can be nested several levels deep.
 302         if block_given? && !matches.empty?
 303           begin
 304             in_scope, @selected = @selected, matches
 305             yield matches
 306           ensure
 307             @selected = in_scope
 308           end
 309         end
 310
 311         # Returns all matches elements.
 312         matches
 313       end
 314
 315       def count_description(min, max) #:nodoc:
 316         pluralize = lambda {|word, quantity| word << (quantity == 1 ? '' : 's')}
 317
 318         if min && max && (max != min)
 319           "between #{min} and #{max} elements"
 320         elsif min && !(min == 1 && max == 1)
 321           "at least #{min} #{pluralize['element', min]}"
 322         elsif max
 323           "at most #{max} #{pluralize['element', max]}"
 324         end
 325       end
 326
 327       # :call-seq:
 328       #   assert_select_rjs(id?) { |elements| ... }
 329       #   assert_select_rjs(statement, id?) { |elements| ... }
 330       #   assert_select_rjs(:insert, position, id?) { |elements| ... }
 331       #
 332       # Selects content from the RJS response.
 333       #
 334       # === Narrowing down
 335       #
 336       # With no arguments, asserts that one or more elements are updated or
 337       # inserted by RJS statements.
 338       #
 339       # Use the +id+ argument to narrow down the assertion to only statements
 340       # that update or insert an element with that identifier.
 341       #
 342       # Use the first argument to narrow down assertions to only statements
 343       # of that type. Possible values are <tt>:replace</tt>, <tt>:replace_html</tt>,
 344       # <tt>:show</tt>, <tt>:hide</tt>, <tt>:toggle</tt>, <tt>:remove</tt> and
 345       # <tt>:insert_html</tt>.
 346       #
 347       # Use the argument <tt>:insert</tt> followed by an insertion position to narrow
 348       # down the assertion to only statements that insert elements in that
 349       # position. Possible values are <tt>:top</tt>, <tt>:bottom</tt>, <tt>:before</tt>
 350       # and <tt>:after</tt>.
 351       #
 352       # Using the <tt>:remove</tt> statement, you will be able to pass a block, but it will
 353       # be ignored as there is no HTML passed for this statement.
 354       #
 355       # === Using blocks
 356       #
 357       # Without a block, +assert_select_rjs+ merely asserts that the response
 358       # contains one or more RJS statements that replace or update content.
 359       #
 360       # With a block, +assert_select_rjs+ also selects all elements used in
 361       # these statements and passes them to the block. Nested assertions are
 362       # supported.
 363       #
 364       # Calling +assert_select_rjs+ with no arguments and using nested asserts
 365       # asserts that the HTML content is returned by one or more RJS statements.
 366       # Using +assert_select+ directly makes the same assertion on the content,
 367       # but without distinguishing whether the content is returned in an HTML
 368       # or JavaScript.
 369       #
 370       # ==== Examples
 371       #
 372       #   # Replacing the element foo.
 373       #   # page.replace 'foo', ...
 374       #   assert_select_rjs :replace, "foo"
 375       #
 376       #   # Replacing with the chained RJS proxy.
 377       #   # page[:foo].replace ...
 378       #   assert_select_rjs :chained_replace, 'foo'
 379       #
 380       #   # Inserting into the element bar, top position.
 381       #   assert_select_rjs :insert, :top, "bar"
 382       #
 383       #   # Remove the element bar
 384       #   assert_select_rjs :remove, "bar"
 385       #
 386       #   # Changing the element foo, with an image.
 387       #   assert_select_rjs "foo" do
 388       #     assert_select "img[src=/images/logo.gif""
 389       #   end
 390       #
 391       #   # RJS inserts or updates a list with four items.
 392       #   assert_select_rjs do
 393       #     assert_select "ol>li", 4
 394       #   end
 395       #
 396       #   # The same, but shorter.
 397       #   assert_select "ol>li", 4
 398       def assert_select_rjs(*args, &block)
 399         rjs_type = args.first.is_a?(Symbol) ? args.shift : nil
 400         id       = args.first.is_a?(String) ? args.shift : nil
 401
 402         # If the first argument is a symbol, it's the type of RJS statement we're looking
 403         # for (update, replace, insertion, etc). Otherwise, we're looking for just about
 404         # any RJS statement.
 405         if rjs_type
 406           if rjs_type == :insert
 407             position  = args.shift
 408             insertion = "insert_#{position}".to_sym
 409             raise ArgumentError, "Unknown RJS insertion type #{position}" unless RJS_STATEMENTS[insertion]
 410             statement = "(#{RJS_STATEMENTS[insertion]})"
 411           else
 412             raise ArgumentError, "Unknown RJS statement type #{rjs_type}" unless RJS_STATEMENTS[rjs_type]
 413             statement = "(#{RJS_STATEMENTS[rjs_type]})"
 414           end
 415         else
 416           statement = "#{RJS_STATEMENTS[:any]}"
 417         end
 418
 419         # Next argument we're looking for is the element identifier. If missing, we pick
 420         # any element, otherwise we replace it in the statement.
 421         pattern = Regexp.new(
 422           id ? statement.gsub(RJS_ANY_ID, "\"#{id}\"") : statement
 423         )
 424
 425         # Duplicate the body since the next step involves destroying it.
 426         matches = nil
 427         case rjs_type
 428           when :remove, :show, :hide, :toggle
 429             matches = @response.body.match(pattern)
 430           else
 431             @response.body.gsub(pattern) do |match|
 432               html = unescape_rjs(match)
 433               matches ||= []
 434               matches.concat HTML::Document.new(html).root.children.select { |n| n.tag? }
 435               ""
 436             end
 437         end
 438
 439         if matches
 440           assert_block("") { true } # to count the assertion
 441           if block_given? && !([:remove, :show, :hide, :toggle].include? rjs_type)
 442             begin
 443               in_scope, @selected = @selected, matches
 444               yield matches
 445             ensure
 446               @selected = in_scope
 447             end
 448           end
 449           matches
 450         else
 451           # RJS statement not found.
 452           case rjs_type
 453             when :remove, :show, :hide, :toggle
 454               flunk_message = "No RJS statement that #{rjs_type.to_s}s '#{id}' was rendered."
 455             else
 456               flunk_message = "No RJS statement that replaces or inserts HTML content."
 457           end
 458           flunk args.shift || flunk_message
 459         end
 460       end
 461
 462       # :call-seq:
 463       #   assert_select_encoded(element?) { |elements| ... }
 464       #
 465       # Extracts the content of an element, treats it as encoded HTML and runs
 466       # nested assertion on it.
 467       #
 468       # You typically call this method within another assertion to operate on
 469       # all currently selected elements. You can also pass an element or array
 470       # of elements.
 471       #
 472       # The content of each element is un-encoded, and wrapped in the root
 473       # element +encoded+. It then calls the block with all un-encoded elements.
 474       #
 475       # ==== Examples
 476       #   # Selects all bold tags from within the title of an ATOM feed's entries (perhaps to nab a section name prefix)
 477       #   assert_select_feed :atom, 1.0 do
 478       #     # Select each entry item and then the title item
 479       #     assert_select "entry>title" do
 480       #       # Run assertions on the encoded title elements
 481       #       assert_select_encoded do
 482       #         assert_select "b"
 483       #       end
 484       #     end
 485       #   end
 486       #
 487       #
 488       #   # Selects all paragraph tags from within the description of an RSS feed
 489       #   assert_select_feed :rss, 2.0 do
 490       #     # Select description element of each feed item.
 491       #     assert_select "channel>item>description" do
 492       #       # Run assertions on the encoded elements.
 493       #       assert_select_encoded do
 494       #         assert_select "p"
 495       #       end
 496       #     end
 497       #   end
 498       def assert_select_encoded(element = nil, &block)
 499         case element
 500           when Array
 501             elements = element
 502           when HTML::Node
 503             elements = [element]
 504           when nil
 505             unless elements = @selected
 506               raise ArgumentError, "First argument is optional, but must be called from a nested assert_select"
 507             end
 508           else
 509             raise ArgumentError, "Argument is optional, and may be node or array of nodes"
 510         end
 511
 512         fix_content = lambda do |node|
 513           # Gets around a bug in the Rails 1.1 HTML parser.
 514           node.content.gsub(/<!\[CDATA\[(.*)(\]\]>)?/m) { CGI.escapeHTML($1) }
 515         end
 516
 517         selected = elements.map do |element|
 518           text = element.children.select{ |c| not c.tag? }.map{ |c| fix_content[c] }.join
 519           root = HTML::Document.new(CGI.unescapeHTML("<encoded>#{text}</encoded>")).root
 520           css_select(root, "encoded:root", &block)[0]
 521         end
 522
 523         begin
 524           old_selected, @selected = @selected, selected
 525           assert_select ":root", &block
 526         ensure
 527           @selected = old_selected
 528         end
 529       end
 530
 531       # :call-seq:
 532       #   assert_select_email { }
 533       #
 534       # Extracts the body of an email and runs nested assertions on it.
 535       #
 536       # You must enable deliveries for this assertion to work, use:
 537       #   ActionMailer::Base.perform_deliveries = true
 538       #
 539       # ==== Examples
 540       #
 541       #  assert_select_email do
 542       #    assert_select "h1", "Email alert"
 543       #  end
 544       #
 545       #  assert_select_email do
 546       #    items = assert_select "ol>li"
 547       #    items.each do
 548       #       # Work with items here...
 549       #    end
 550       #  end
 551       #
 552       def assert_select_email(&block)
 553         deliveries = ActionMailer::Base.deliveries
 554         assert !deliveries.empty?, "No e-mail in delivery list"
 555
 556         for delivery in deliveries
 557           for part in delivery.parts
 558             if part["Content-Type"].to_s =~ /^text\/html\W/
 559               root = HTML::Document.new(part.body).root
 560               assert_select root, ":root", &block
 561             end
 562           end
 563         end
 564       end
 565
 566       protected
 567         unless const_defined?(:RJS_STATEMENTS)
 568           RJS_PATTERN_HTML  = "\"((\\\\\"|[^\"])*)\""
 569           RJS_ANY_ID        = "\"([^\"])*\""
 570           RJS_STATEMENTS    = {
 571             :chained_replace      => "\\$\\(#{RJS_ANY_ID}\\)\\.replace\\(#{RJS_PATTERN_HTML}\\)",
 572             :chained_replace_html => "\\$\\(#{RJS_ANY_ID}\\)\\.update\\(#{RJS_PATTERN_HTML}\\)",
 573             :replace_html         => "Element\\.update\\(#{RJS_ANY_ID}, #{RJS_PATTERN_HTML}\\)",
 574             :replace              => "Element\\.replace\\(#{RJS_ANY_ID}, #{RJS_PATTERN_HTML}\\)"
 575           }
 576           [:remove, :show, :hide, :toggle].each do |action|
 577             RJS_STATEMENTS[action] = "Element\\.#{action}\\(#{RJS_ANY_ID}\\)"
 578           end
 579           RJS_INSERTIONS = ["top", "bottom", "before", "after"]
 580           RJS_INSERTIONS.each do |insertion|
 581             RJS_STATEMENTS["insert_#{insertion}".to_sym] = "Element.insert\\(#{RJS_ANY_ID}, \\{ #{insertion}: #{RJS_PATTERN_HTML} \\}\\)"
 582           end
 583           RJS_STATEMENTS[:insert_html] = "Element.insert\\(#{RJS_ANY_ID}, \\{ (#{RJS_INSERTIONS.join('|')}): #{RJS_PATTERN_HTML} \\}\\)"
 584           RJS_STATEMENTS[:any] = Regexp.new("(#{RJS_STATEMENTS.values.join('|')})")
 585           RJS_PATTERN_UNICODE_ESCAPED_CHAR = /\\u([0-9a-zA-Z]{4})/
 586         end
 587
 588         # +assert_select+ and +css_select+ call this to obtain the content in the HTML
 589         # page, or from all the RJS statements, depending on the type of response.
 590         def response_from_page_or_rjs()
 591           content_type = @response.content_type
 592
 593           if content_type && content_type =~ /text\/javascript/
 594             body = @response.body.dup
 595             root = HTML::Node.new(nil)
 596
 597             while true
 598               next if body.sub!(RJS_STATEMENTS[:any]) do |match|
 599                 html = unescape_rjs(match)
 600                 matches = HTML::Document.new(html).root.children.select { |n| n.tag? }
 601                 root.children.concat matches
 602                 ""
 603               end
 604               break
 605             end
 606
 607             root
 608           else
 609             html_document.root
 610           end
 611         end
 612
 613         # Unescapes a RJS string.
 614         def unescape_rjs(rjs_string)
 615           # RJS encodes double quotes and line breaks.
 616           unescaped= rjs_string.gsub('\"', '"')
 617           unescaped.gsub!(/\\\//, '/')
 618           unescaped.gsub!('\n', "\n")
 619           unescaped.gsub!('\076', '>')
 620           unescaped.gsub!('\074', '<')
 621           # RJS encodes non-ascii characters.
 622           unescaped.gsub!(RJS_PATTERN_UNICODE_ESCAPED_CHAR) {|u| [$1.hex].pack('U*')}
 623           unescaped
 624         end
 625     end
 626   end
 627 end