Adds the assert_select method for use in Rails functional test cases.
Use assert_select 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_rjs —
Assertions on HTML content of RJS update and
insertion operations.
- 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 for learning how to use selectors.
- assert_select
- assert_select_email
- assert_select_encoded
- assert_select_rjs
- css_select
- response_from_page_or_rjs
- unescape_rjs
RJS_STATEMENTS | = | { :replace => /Element\.replace/, :replace_html => /Element\.update/, :chained_replace => /\.replace/, :chained_replace_html => /\.update/, } |
RJS_INSERTIONS | = | [:top, :bottom, :before, :after] |
RJS_PATTERN_HTML | = | /"((\\"|[^"])*)"/ |
RJS_PATTERN_EVERYTHING | = | Regexp.new("#{RJS_STATEMENTS[:any]}\\(\"([^\"]*)\", #{RJS_PATTERN_HTML}\\)", Regexp::MULTILINE) |
RJS_PATTERN_UNICODE_ESCAPED_CHAR | = | /\\u([0-9a-zA-Z]{4})/ |
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 will select from the response HTML. Calling assert_select inside an assert_select block will run the assertion for each element selected by the enclosing assertion.
For example:
assert_select "ol>li" do |elements| elements.each do |element| assert_select element, "li" end end
Or for short:
assert_select "ol>li" do assert_select "li" 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:
- true — Assertion is true if at least one element selected.
- false — Assertion is true if no element selected.
- String/Regexp — Assertion is true if the text value of at least one element matches the string or regular expression.
- Integer — Assertion is true if exactly that number of elements are selected.
- Range — 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:
- :text — Narrow the selection to elements that have this text value (string or regexp).
- :html — Narrow the selection to elements that have this HTML content (string or regexp).
- :count — Assertion is true if the number of selected elements is equal to this value.
- :minimum — Assertion is true if the number of selected elements is at least this value.
- :maximum — 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.
Examples
# 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
[ show source ]
# File vendor/rails/actionpack/lib/action_controller/assertions/selector_assertions.rb, line 179 179: def assert_select(*args, &block) 180: # Start with optional element followed by mandatory selector. 181: arg = args.shift 182: 183: if arg.is_a?(HTML::Node) 184: # First argument is a node (tag or text, but also HTML root), 185: # so we know what we're selecting from. 186: root = arg 187: arg = args.shift 188: elsif arg == nil 189: # This usually happens when passing a node/element that 190: # happens to be nil. 191: 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?" 192: elsif @selected 193: root = HTML::Node.new(nil) 194: root.children.concat @selected 195: else 196: # Otherwise just operate on the response document. 197: root = response_from_page_or_rjs 198: end 199: 200: # First or second argument is the selector: string and we pass 201: # all remaining arguments. Array and we pass the argument. Also 202: # accepts selector itself. 203: case arg 204: when String 205: selector = HTML::Selector.new(arg, args) 206: when Array 207: selector = HTML::Selector.new(*arg) 208: when HTML::Selector 209: selector = arg 210: else raise ArgumentError, "Expecting a selector as the first argument" 211: end 212: 213: # Next argument is used for equality tests. 214: equals = {} 215: case arg = args.shift 216: when Hash 217: equals = arg 218: when String, Regexp 219: equals[:text] = arg 220: when Integer 221: equals[:count] = arg 222: when Range 223: equals[:minimum] = arg.begin 224: equals[:maximum] = arg.end 225: when FalseClass 226: equals[:count] = 0 227: when NilClass, TrueClass 228: equals[:minimum] = 1 229: else raise ArgumentError, "I don't understand what you're trying to match" 230: end 231: 232: # By default we're looking for at least one match. 233: if equals[:count] 234: equals[:minimum] = equals[:maximum] = equals[:count] 235: else 236: equals[:minimum] = 1 unless equals[:minimum] 237: end 238: 239: # Last argument is the message we use if the assertion fails. 240: message = args.shift 241: #- message = "No match made with selector #{selector.inspect}" unless message 242: if args.shift 243: raise ArgumentError, "Not expecting that last argument, you either have too many arguments, or they're the wrong type" 244: end 245: 246: matches = selector.select(root) 247: # If text/html, narrow down to those elements that match it. 248: content_mismatch = nil 249: if match_with = equals[:text] 250: matches.delete_if do |match| 251: text = "" 252: stack = match.children.reverse 253: while node = stack.pop 254: if node.tag? 255: stack.concat node.children.reverse 256: else 257: text << node.content 258: end 259: end 260: text.strip! unless NO_STRIP.include?(match.name) 261: unless match_with.is_a?(Regexp) ? (text =~ match_with) : (text == match_with.to_s) 262: content_mismatch ||= build_message(message, "<?> expected but was\n<?>.", match_with, text) 263: true 264: end 265: end 266: elsif match_with = equals[:html] 267: matches.delete_if do |match| 268: html = match.children.map(&:to_s).join 269: html.strip! unless NO_STRIP.include?(match.name) 270: unless match_with.is_a?(Regexp) ? (html =~ match_with) : (html == match_with.to_s) 271: content_mismatch ||= build_message(message, "<?> expected but was\n<?>.", match_with, html) 272: true 273: end 274: end 275: end 276: # Expecting foo found bar element only if found zero, not if 277: # found one but expecting two. 278: message ||= content_mismatch if matches.empty? 279: # Test minimum/maximum occurrence. 280: if equals[:minimum] 281: assert matches.size >= equals[:minimum], message || 282: "Expected at least #{equals[:minimum]} elements, found #{matches.size}." 283: end 284: if equals[:maximum] 285: assert matches.size <= equals[:maximum], message || 286: "Expected at most #{equals[:maximum]} elements, found #{matches.size}." 287: end 288: 289: # If a block is given call that block. Set @selected to allow 290: # nested assert_select, which can be nested several levels deep. 291: if block_given? && !matches.empty? 292: begin 293: in_scope, @selected = @selected, matches 294: yield matches 295: ensure 296: @selected = in_scope 297: end 298: end 299: 300: # Returns all matches elements. 301: matches 302: 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
Example
assert_select "h1", "Email alert"
end
[ show source ]
# File vendor/rails/actionpack/lib/action_controller/assertions/selector_assertions.rb, line 501 501: def assert_select_email(&block) 502: deliveries = ActionMailer::Base.deliveries 503: assert !deliveries.empty?, "No e-mail in delivery list" 504: 505: for delivery in deliveries 506: for part in delivery.parts 507: if part["Content-Type"].to_s =~ /^text\/html\W/ 508: root = HTML::Document.new(part.body).root 509: assert_select root, ":root", &block 510: end 511: end 512: end 513: 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.
Example
assert_select_feed :rss, 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
[ show source ]
# File vendor/rails/actionpack/lib/action_controller/assertions/selector_assertions.rb, line 455 455: def assert_select_encoded(element = nil, &block) 456: case element 457: when Array 458: elements = element 459: when HTML::Node 460: elements = [element] 461: when nil 462: unless elements = @selected 463: raise ArgumentError, "First argument is optional, but must be called from a nested assert_select" 464: end 465: else 466: raise ArgumentError, "Argument is optional, and may be node or array of nodes" 467: end 468: 469: fix_content = lambda do |node| 470: # Gets around a bug in the Rails 1.1 HTML parser. 471: node.content.gsub(/<!\[CDATA\[(.*)(\]\]>)?/m) { CGI.escapeHTML($1) } 472: end 473: 474: selected = elements.map do |element| 475: text = element.children.select{ |c| not c.tag? }.map{ |c| fix_content[c] }.join 476: root = HTML::Document.new(CGI.unescapeHTML("<encoded>#{text}</encoded>")).root 477: css_select(root, "encoded:root", &block)[0] 478: end 479: 480: begin 481: old_selected, @selected = @selected, selected 482: assert_select ":root", &block 483: ensure 484: @selected = old_selected 485: end 486: end
assert_select_rjs(statement, id?) { |elements| ... }
assert_select_rjs(:insert, position, id?) { |elements| ... }
Selects content from the RJS response.
Narrowing down
With no arguments, asserts that one or more elements are updated or inserted by RJS statements.
Use the id argument to narrow down the assertion to only statements that update or insert an element with that identifier.
Use the first argument to narrow down assertions to only statements of that type. Possible values are +:replace+, +:replace_html+ and +:insert_html+.
Use the argument +:insert+ followed by an insertion position to narrow down the assertion to only statements that insert elements in that position. Possible values are +:top+, +:bottom+, +:before+ and +:after+.
Using blocks
Without a block, assert_select_rjs merely asserts that the response contains one or more RJS statements that replace or update content.
With a block, assert_select_rjs also selects all elements used in these statements and passes them to the block. Nested assertions are supported.
Calling assert_select_rjs with no arguments and using nested asserts asserts that the HTML content is returned by one or more RJS statements. Using assert_select directly makes the same assertion on the content, but without distinguishing whether the content is returned in an HTML or JavaScript.
Examples
# Replacing the element foo. # page.replace 'foo', ... assert_select_rjs :replace, "foo" # Replacing with the chained RJS proxy. # page[:foo].replace ... assert_select_rjs :chained_replace, 'foo' # Inserting into the element bar, top position. assert_select_rjs :insert, :top, "bar" # Changing the element foo, with an image. assert_select_rjs "foo" do assert_select "img[src=/images/logo.gif"" end # RJS inserts or updates a list with four items. assert_select_rjs do assert_select "ol>li", 4 end # The same, but shorter. assert_select "ol>li", 4
[ show source ]
# File vendor/rails/actionpack/lib/action_controller/assertions/selector_assertions.rb, line 367 367: def assert_select_rjs(*args, &block) 368: rjs_type = nil 369: arg = args.shift 370: 371: # If the first argument is a symbol, it's the type of RJS statement we're looking 372: # for (update, replace, insertion, etc). Otherwise, we're looking for just about 373: # any RJS statement. 374: if arg.is_a?(Symbol) 375: rjs_type = arg 376: if rjs_type == :insert 377: arg = args.shift 378: insertion = "insert_#{arg}".to_sym 379: raise ArgumentError, "Unknown RJS insertion type #{arg}" unless RJS_STATEMENTS[insertion] 380: statement = "(#{RJS_STATEMENTS[insertion]})" 381: else 382: raise ArgumentError, "Unknown RJS statement type #{rjs_type}" unless RJS_STATEMENTS[rjs_type] 383: statement = "(#{RJS_STATEMENTS[rjs_type]})" 384: end 385: arg = args.shift 386: else 387: statement = "#{RJS_STATEMENTS[:any]}" 388: end 389: 390: # Next argument we're looking for is the element identifier. If missing, we pick 391: # any element. 392: if arg.is_a?(String) 393: id = Regexp.quote(arg) 394: arg = args.shift 395: else 396: id = "[^\"]*" 397: end 398: 399: pattern = 400: case rjs_type 401: when :chained_replace, :chained_replace_html 402: Regexp.new("\\$\\(\"#{id}\"\\)#{statement}\\(#{RJS_PATTERN_HTML}\\)", Regexp::MULTILINE) 403: else 404: Regexp.new("#{statement}\\(\"#{id}\", #{RJS_PATTERN_HTML}\\)", Regexp::MULTILINE) 405: end 406: 407: # Duplicate the body since the next step involves destroying it. 408: matches = nil 409: @response.body.gsub(pattern) do |match| 410: html = unescape_rjs($2) 411: matches ||= [] 412: matches.concat HTML::Document.new(html).root.children.select { |n| n.tag? } 413: "" 414: end 415: if matches 416: if block_given? 417: begin 418: in_scope, @selected = @selected, matches 419: yield matches 420: ensure 421: @selected = in_scope 422: end 423: end 424: matches 425: else 426: # RJS statement not found. 427: flunk args.shift || "No RJS statement that replaces or inserts HTML content." 428: end 429: end
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.
For example:
forms = css_select("form") forms.each do |form| inputs = css_select(form, "input") ... end
[ show source ]
# File vendor/rails/actionpack/lib/action_controller/assertions/selector_assertions.rb, line 58 58: def css_select(*args) 59: # See assert_select to understand what's going on here. 60: arg = args.shift 61: 62: if arg.is_a?(HTML::Node) 63: root = arg 64: arg = args.shift 65: elsif arg == nil 66: 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?" 67: elsif @selected 68: matches = [] 69: @selected.each do |selected| 70: subset = css_select(selected, HTML::Selector.new(arg.dup, args.dup)) 71: subset.each do |match| 72: matches << match unless matches.any? { |m| m.equal?(match) } 73: end 74: end 75: 76: return matches 77: else 78: root = response_from_page_or_rjs 79: end 80: 81: case arg 82: when String 83: selector = HTML::Selector.new(arg, args) 84: when Array 85: selector = HTML::Selector.new(*arg) 86: when HTML::Selector 87: selector = arg 88: else raise ArgumentError, "Expecting a selector as the first argument" 89: end 90: 91: selector.select(root) 92: end
assert_select and css_select call this to obtain the content in the HTML page, or from all the RJS statements, depending on the type of response.
[ show source ]
# File vendor/rails/actionpack/lib/action_controller/assertions/selector_assertions.rb, line 539 539: def response_from_page_or_rjs() 540: content_type = @response.headers["Content-Type"] 541: if content_type && content_type =~ /text\/javascript/ 542: body = @response.body.dup 543: root = HTML::Node.new(nil) 544: while true 545: next if body.sub!(RJS_PATTERN_EVERYTHING) do |match| 546: html = unescape_rjs($3) 547: matches = HTML::Document.new(html).root.children.select { |n| n.tag? } 548: root.children.concat matches 549: "" 550: end 551: break 552: end 553: root 554: else 555: html_document.root 556: end 557: end
Unescapes a RJS string.
[ show source ]
# File vendor/rails/actionpack/lib/action_controller/assertions/selector_assertions.rb, line 560 560: def unescape_rjs(rjs_string) 561: # RJS encodes double quotes and line breaks. 562: unescaped= rjs_string.gsub('\"', '"') 563: unescaped.gsub!('\n', "\n") 564: # RJS encodes non-ascii characters. 565: unescaped.gsub!(RJS_PATTERN_UNICODE_ESCAPED_CHAR) {|u| [$1.hex].pack('U*')} 566: unescaped 567: end