integration.rb 25.7 KB
Newer Older
1 2
require 'stringio'
require 'uri'
3
require 'active_support/core_ext/kernel/singleton_class'
4
require 'active_support/core_ext/object/try'
5
require 'active_support/core_ext/string/strip'
J
Joshua Peek 已提交
6
require 'rack/test'
7
require 'minitest'
8 9

module ActionDispatch
D
David Heinemeier Hansson 已提交
10
  module Integration #:nodoc:
11 12 13 14 15
    module RequestHelpers
      # Performs a GET request with the given parameters.
      #
      # - +path+: The URI (as a String) on which you want to perform a GET
      #   request.
16
      # - +params+: The HTTP parameters that you want to pass. This may
17 18 19 20
      #   be +nil+,
      #   a Hash, or a String that is appropriately encoded
      #   (<tt>application/x-www-form-urlencoded</tt> or
      #   <tt>multipart/form-data</tt>).
21
      # - +headers+: Additional headers to pass, as a Hash. The headers will be
22
      #   merged into the Rack env hash.
23
      # - +env+: Additional env to pass, as a Hash. The headers will be
24
      #   merged into the Rack env hash.
25
      #
R
Robin Dupret 已提交
26
      # This method returns a Response object, which one can use to
27
      # inspect the details of the response. Furthermore, if this method was
28
      # called from an ActionDispatch::IntegrationTest object, then that
29 30 31
      # object's <tt>@response</tt> instance variable will point to the same
      # response object.
      #
32 33
      # You can also perform POST, PATCH, PUT, DELETE, and HEAD requests with
      # +#post+, +#patch+, +#put+, +#delete+, and +#head+.
34 35 36 37
      #
      # Example:
      #
      #   get '/feed', params: { since: 201501011400 }
38
      #   post '/profile', headers: { "X-Test-Header" => "testvalue" }
39 40
      def get(path, *args)
        process_with_kwargs(:get, path, *args)
41 42
      end

43
      # Performs a POST request with the given parameters. See +#get+ for more
44
      # details.
45 46
      def post(path, *args)
        process_with_kwargs(:post, path, *args)
47 48
      end

49 50
      # Performs a PATCH request with the given parameters. See +#get+ for more
      # details.
51 52
      def patch(path, *args)
        process_with_kwargs(:patch, path, *args)
53 54
      end

55
      # Performs a PUT request with the given parameters. See +#get+ for more
56
      # details.
57 58
      def put(path, *args)
        process_with_kwargs(:put, path, *args)
59 60
      end

61
      # Performs a DELETE request with the given parameters. See +#get+ for
62
      # more details.
63 64
      def delete(path, *args)
        process_with_kwargs(:delete, path, *args)
65 66
      end

67
      # Performs a HEAD request with the given parameters. See +#get+ for more
68
      # details.
69 70
      def head(path, *args)
        process_with_kwargs(:head, path, *args)
71 72 73
      end

      # Performs an XMLHttpRequest request with the given parameters, mirroring
S
Sean Griffin 已提交
74
      # an AJAX request made from JavaScript.
75
      #
76 77
      # The request_method is +:get+, +:post+, +:patch+, +:put+, +:delete+ or
      # +:head+; the parameters are +nil+, a hash, or a url-encoded or multipart
78
      # string; the headers are a hash.
79 80 81 82 83
      #
      # Example:
      #
      #   xhr :get, '/feed', params: { since: 201501011400 }
      def xml_http_request(request_method, path, *args)
84
        if kwarg_request?(args)
85 86 87 88 89 90 91 92 93 94 95
          params, headers, env = args.first.values_at(:params, :headers, :env)
        else
          params = args[0]
          headers = args[1]
          env = {}

          if params.present? || headers.present?
            non_kwarg_request_warning
          end
        end

96 97 98 99 100 101
        ActiveSupport::Deprecation.warn(<<-MSG.strip_heredoc)
          xhr and xml_http_request methods are deprecated in favor of
          `get "/posts", xhr: true` and `post "/posts/1", xhr: true`
        MSG

        process(request_method, path, params: params, headers: headers, xhr: true)
102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117
      end
      alias xhr :xml_http_request

      # Follow a single redirect response. If the last response was not a
      # redirect, an exception will be raised. Otherwise, the redirect is
      # performed on the location header.
      def follow_redirect!
        raise "not a redirect! #{status} #{status_message}" unless redirect?
        get(response.location)
        status
      end

      # Performs a request using the specified method, following any subsequent
      # redirect. Note that the redirects are followed until the response is
      # not a redirect--this means you may run into an infinite loop if your
      # redirect loops back to itself.
118 119 120 121 122
      #
      # Example:
      #
      #   request_via_redirect :post, '/welcome',
      #     params: { ref_id: 14 },
123
      #     headers: { "X-Test-Header" => "testvalue" }
124 125 126
      def request_via_redirect(http_method, path, *args)
        process_with_kwargs(http_method, path, *args)

127 128 129 130 131 132
        follow_redirect! while redirect?
        status
      end

      # Performs a GET request, following any subsequent redirect.
      # See +request_via_redirect+ for more information.
133
      def get_via_redirect(path, *args)
134
        ActiveSupport::Deprecation.warn('`get_via_redirect` is deprecated and will be removed in Rails 5.1. Please use follow_redirect! manually after the request call for the same behavior.')
135
        request_via_redirect(:get, path, *args)
136 137 138 139
      end

      # Performs a POST request, following any subsequent redirect.
      # See +request_via_redirect+ for more information.
140
      def post_via_redirect(path, *args)
141
        ActiveSupport::Deprecation.warn('`post_via_redirect` is deprecated and will be removed in Rails 5.1. Please use follow_redirect! manually after the request call for the same behavior.')
142
        request_via_redirect(:post, path, *args)
143 144
      end

145 146
      # Performs a PATCH request, following any subsequent redirect.
      # See +request_via_redirect+ for more information.
147
      def patch_via_redirect(path, *args)
148
        ActiveSupport::Deprecation.warn('`patch_via_redirect` is deprecated and will be removed in Rails 5.1. Please use follow_redirect! manually after the request call for the same behavior.')
149
        request_via_redirect(:patch, path, *args)
150 151
      end

152 153
      # Performs a PUT request, following any subsequent redirect.
      # See +request_via_redirect+ for more information.
154
      def put_via_redirect(path, *args)
155
        ActiveSupport::Deprecation.warn('`put_via_redirect` is deprecated and will be removed in Rails 5.1. Please use follow_redirect! manually after the request call for the same behavior.')
156
        request_via_redirect(:put, path, *args)
157 158 159 160
      end

      # Performs a DELETE request, following any subsequent redirect.
      # See +request_via_redirect+ for more information.
161
      def delete_via_redirect(path, *args)
162
        ActiveSupport::Deprecation.warn('`delete_via_redirect` is deprecated and will be removed in Rails 5.1. Please use follow_redirect! manually after the request call for the same behavior.')
163
        request_via_redirect(:delete, path, *args)
164 165 166
      end
    end

167 168
    # An instance of this class represents a set of requests and responses
    # performed sequentially by a test process. Because you can instantiate
169 170 171
    # multiple sessions and run them side-by-side, you can also mimic (to some
    # limited extent) multiple simultaneous users interacting with your system.
    #
172 173 174
    # Typically, you will instantiate a new session using
    # IntegrationTest#open_session, rather than instantiating
    # Integration::Session directly.
175
    class Session
176 177
      DEFAULT_HOST = "www.example.com"

178
      include Minitest::Assertions
J
Joshua Peek 已提交
179
      include TestProcess, RequestHelpers, Assertions
180

181 182 183
      %w( status status_message headers body redirect? ).each do |method|
        delegate method, :to => :response, :allow_nil => true
      end
184

185 186 187
      %w( path ).each do |method|
        delegate method, :to => :request, :allow_nil => true
      end
188 189

      # The hostname used in the last request.
190 191 192 193
      def host
        @host || DEFAULT_HOST
      end
      attr_writer :host
194 195 196

      # The remote_addr used in the last request.
      attr_accessor :remote_addr
197

198 199 200
      # The Accept header to send.
      attr_accessor :accept

201 202
      # A map of the cookies returned by the last response, and which will be
      # sent with the next request.
203
      def cookies
204
        _mock_session.cookie_jar
205
      end
206 207 208 209 210 211 212 213 214 215

      # A reference to the controller instance used by the last request.
      attr_reader :controller

      # A reference to the request instance used by the last request.
      attr_reader :request

      # A reference to the response instance used by the last request.
      attr_reader :response

216 217 218
      # A running counter of the number of requests processed.
      attr_accessor :request_count

219 220
      include ActionDispatch::Routing::UrlFor

P
Pratik Naik 已提交
221
      # Create and initialize a new Session instance.
222
      def initialize(app)
J
José Valim 已提交
223
        super()
224
        @app = app
225

226 227 228
        reset!
      end

229 230 231 232
      def url_options
        @url_options ||= default_url_options.dup.tap do |url_options|
          url_options.reverse_merge!(controller.url_options) if controller

233
          if @app.respond_to?(:routes)
234 235 236 237 238
            url_options.reverse_merge!(@app.routes.default_url_options)
          end

          url_options.reverse_merge!(:host => host, :protocol => https? ? "https" : "http")
        end
239 240
      end

241 242 243 244 245 246 247 248
      # Resets the instance. This can be used to reset the state information
      # in an existing session instance, so it can be used from a clean-slate
      # condition.
      #
      #   session.reset!
      def reset!
        @https = false
        @controller = @request = @response = nil
249
        @_mock_session = nil
250
        @request_count = 0
251
        @url_options = nil
252

253
        self.host        = DEFAULT_HOST
254
        self.remote_addr = "127.0.0.1"
255 256 257
        self.accept      = "text/xml,application/xml,application/xhtml+xml," +
                           "text/html;q=0.9,text/plain;q=0.8,image/png," +
                           "*/*;q=0.5"
J
Jamis Buck 已提交
258

259
        unless defined? @named_routes_configured
J
Jamis Buck 已提交
260 261 262 263
          # the helpers are made protected by default--we make them public for
          # easier access during testing and troubleshooting.
          @named_routes_configured = true
        end
264 265 266 267 268 269
      end

      # Specify whether or not the session should mimic a secure HTTPS request.
      #
      #   session.https!
      #   session.https!(false)
270
      def https!(flag = true)
271
        @https = flag
272 273
      end

274
      # Returns +true+ if the session is mimicking a secure HTTPS request.
275 276 277 278 279 280 281 282 283 284
      #
      #   if session.https?
      #     ...
      #   end
      def https?
        @https
      end

      # Set the host name to use in the next request.
      #
285
      #   session.host! "www.example.com"
A
Aaron Patterson 已提交
286
      alias :host! :host=
287 288

      private
289 290 291
        def _mock_session
          @_mock_session ||= Rack::MockSession.new(@app, host)
        end
292

293
        def process_with_kwargs(http_method, path, *args)
294
          if kwarg_request?(args)
295 296
            process(http_method, path, *args)
          else
297
            non_kwarg_request_warning if args.any?
298 299 300 301
            process(http_method, path, { params: args[0], headers: args[1] })
          end
        end

302
        REQUEST_KWARGS = %i(params headers env xhr)
303
        def kwarg_request?(args)
304 305 306 307 308
          args[0].respond_to?(:keys) && args[0].keys.any? { |k| REQUEST_KWARGS.include?(k) }
        end

        def non_kwarg_request_warning
          ActiveSupport::Deprecation.warn(<<-MSG.strip_heredoc)
309
            ActionDispatch::IntegrationTest HTTP request methods will accept only
G
Guo Xiang Tan 已提交
310 311
            the following keyword arguments in future Rails versions:
            #{REQUEST_KWARGS.join(', ')}
312 313 314 315 316 317

            Examples:

            get '/profile',
              params: { id: 1 },
              headers: { 'X-Extra-Header' => '123' },
A
Arthur Neves 已提交
318
              env: { 'action_dispatch.custom' => 'custom' },
G
Guo Xiang Tan 已提交
319
              xhr: true
320 321 322
          MSG
        end

323
        # Performs the actual request.
324 325 326
        def process(method, path, params: nil, headers: nil, env: nil, xhr: false, as: nil)
          request_encoder = RequestEncoder.encoder(as)

327 328 329
          if path =~ %r{://}
            location = URI.parse(path)
            https! URI::HTTPS === location if location.scheme
330 331 332 333 334
            if url_host = location.host
              default = Rack::Request::DEFAULT_PORTS[location.scheme]
              url_host += ":#{location.port}" if default != location.port
              host! url_host
            end
335 336 337 338
            path = request_encoder.append_format_to location.path
            path = location.query ? "#{path}?#{location.query}" : path
          else
            path = request_encoder.append_format_to path
339
          end
340

341
          hostname, port = host.split(':')
342

343
          request_env = {
344
            :method => method,
345
            :params => request_encoder.encode_params(params),
346

347
            "SERVER_NAME"     => hostname,
348
            "SERVER_PORT"     => port || (https? ? "443" : "80"),
349 350 351
            "HTTPS"           => https? ? "on" : "off",
            "rack.url_scheme" => https? ? "https" : "http",

352
            "REQUEST_URI"    => path,
353
            "HTTP_HOST"      => host,
354
            "REMOTE_ADDR"    => remote_addr,
355
            "CONTENT_TYPE"   => request_encoder.content_type,
356
            "HTTP_ACCEPT"    => accept
357
          }
358 359 360 361

          if xhr
            headers ||= {}
            headers['HTTP_X_REQUESTED_WITH'] = 'XMLHttpRequest'
362
            headers['HTTP_ACCEPT'] ||= [Mime[:js], Mime[:html], Mime[:xml], 'text/xml', '*/*'].join(', ')
363 364
          end

365 366
          # this modifies the passed request_env directly
          if headers.present?
367
            Http::Headers.from_hash(request_env).merge!(headers)
368 369
          end
          if env.present?
370
            Http::Headers.from_hash(request_env).merge!(env)
371
          end
372

373
          session = Rack::Test::Session.new(_mock_session)
374

375 376
          # NOTE: rack-test v0.5 doesn't build a default uri correctly
          # Make sure requested path is always a full uri
377
          session.request(build_full_uri(path, request_env), request_env)
378

379
          @request_count += 1
380
          @request  = ActionDispatch::Request.new(session.last_request.env)
381
          response = _mock_session.last_response
382
          @response = ActionDispatch::TestResponse.from_response(response)
E
eileencodes 已提交
383
          @response.request = @request
384
          @response.response_parser = RequestEncoder.parser(@response.content_type)
385
          @html_document = nil
386
          @url_options = nil
387

388
          @controller = @request.controller_instance
389

390
          response.status
391
        end
392 393 394 395

        def build_full_uri(path, env)
          "#{env['rack.url_scheme']}://#{env['SERVER_NAME']}:#{env['SERVER_PORT']}#{path}"
        end
396 397 398 399

        class RequestEncoder # :nodoc:
          @encoders = {}

400 401
          attr_reader :response_parser

402
          def initialize(mime_name, param_encoder, response_parser, url_encoded_form = false)
403 404 405 406 407 408 409 410 411
            @mime = Mime[mime_name]

            unless @mime
              raise ArgumentError, "Can't register a request encoder for " \
                "unregistered MIME Type: #{mime_name}. See `Mime::Type.register`."
            end

            @url_encoded_form = url_encoded_form
            @path_format      = ".#{@mime.symbol}" unless @url_encoded_form
412 413
            @response_parser  = response_parser || -> body { body }
            @param_encoder    = param_encoder   || :"to_#{@mime.symbol}".to_proc
414 415 416 417 418 419 420 421 422 423 424 425 426 427 428
          end

          def append_format_to(path)
            path << @path_format unless @url_encoded_form
            path
          end

          def content_type
            @mime.to_s
          end

          def encode_params(params)
            @param_encoder.call(params)
          end

429 430 431
          def self.parser(content_type)
            mime = Mime::Type.lookup(content_type)
            encoder(mime ? mime.ref : nil).response_parser
432 433
          end

434 435 436 437
          def self.encoder(name)
            @encoders[name] || WWWFormEncoder
          end

438 439
          def self.register_encoder(mime_name, param_encoder: nil, response_parser: nil)
            @encoders[mime_name] = new(mime_name, param_encoder, response_parser)
440 441
          end

442
          register_encoder :json, response_parser: -> body { JSON.parse(body) }
443

444
          WWWFormEncoder = new(:url_encoded_form, -> params { params }, nil, true)
445
        end
446 447
    end

448
    module Runner
449 450
      include ActionDispatch::Assertions

451 452
      APP_SESSIONS = {}

453 454
      attr_reader :app

455
      def before_setup # :nodoc:
456 457
        @app = nil
        @integration_session = nil
458 459 460 461 462 463
        @execution_context = nil
        super
      end

      def after_teardown # :nodoc:
        remove!
E
eileencodes 已提交
464
        super
465 466 467
      end

      def integration_session
468
        @integration_session ||= create_session(app).tap { @execution_context = app.respond_to?(:executor) && app.executor.run! }
469 470
      end

471 472 473
      # Reset the current session. This is useful for testing multiple sessions
      # in a single test case.
      def reset!
474 475
        remove!
        integration_session
476 477 478 479 480 481 482 483 484 485 486 487
      end

      def create_session(app)
        klass = APP_SESSIONS[app] ||= Class.new(Integration::Session) {
          # If the app is a Rails app, make url_helpers available on the session
          # This makes app.url_for and app.foo_path available in the console
          if app.respond_to?(:routes)
            include app.routes.url_helpers
            include app.routes.mounted_helpers
          end
        }
        klass.new(app)
488 489
      end

490
      def remove! # :nodoc:
491 492
        @execution_context.complete! if @execution_context
        @execution_context = nil
493 494 495
        @integration_session = nil
      end

496
      %w(get post patch put head delete cookies assigns
497
         xml_http_request xhr get_via_redirect post_via_redirect).each do |method|
498
        define_method(method) do |*args|
499 500 501 502 503
          # reset the html_document variable, except for cookies/assigns calls
          unless method == 'cookies' || method == 'assigns'
            @html_document = nil
          end

504
          integration_session.__send__(method, *args).tap do
505 506 507 508 509 510 511 512 513 514 515 516 517 518 519
            copy_session_variables!
          end
        end
      end

      # Open a new session instance. If a block is given, the new session is
      # yielded to the block before being returned.
      #
      #   session = open_session do |sess|
      #     sess.extend(CustomAssertions)
      #   end
      #
      # By default, a single session is automatically created for you, but you
      # can use this method to open multiple sessions that ought to be tested
      # simultaneously.
G
Guo Xiang Tan 已提交
520
      def open_session
521 522
        dup.tap do |session|
          yield session if block_given?
523 524 525 526 527 528
        end
      end

      # Copy the instance variables from the current session instance into the
      # test instance.
      def copy_session_variables! #:nodoc:
A
Aaron Patterson 已提交
529 530 531
        @controller = @integration_session.controller
        @response   = @integration_session.response
        @request    = @integration_session.request
532 533
      end

534 535 536
      def default_url_options
        integration_session.default_url_options
      end
537

538 539
      def default_url_options=(options)
        integration_session.default_url_options = options
540 541
      end

542
      def respond_to?(method, include_private = false)
543
        integration_session.respond_to?(method, include_private) || super
544 545
      end

546 547
      # Delegate unhandled messages to the current session instance.
      def method_missing(sym, *args, &block)
548 549
        if integration_session.respond_to?(sym)
          integration_session.__send__(sym, *args, &block).tap do
550 551 552 553
            copy_session_variables!
          end
        else
          super
554 555 556
        end
      end
    end
557 558
  end

559
  # An integration test spans multiple controllers and actions,
560 561 562 563
  # tying them all together to ensure they work together as expected. It tests
  # more completely than either unit or functional tests do, exercising the
  # entire stack, from the dispatcher to the database.
  #
564
  # At its simplest, you simply extend <tt>IntegrationTest</tt> and write your tests
565 566
  # using the get/post methods:
  #
567
  #   require "test_helper"
568
  #
569
  #   class ExampleTest < ActionDispatch::IntegrationTest
570 571 572 573 574 575 576 577
  #     fixtures :people
  #
  #     def test_login
  #       # get the login page
  #       get "/login"
  #       assert_equal 200, status
  #
  #       # post the login and follow through to the home page
578 579
  #       post "/login", params: { username: people(:jamis).username,
  #         password: people(:jamis).password }
580 581 582 583 584 585 586 587 588
  #       follow_redirect!
  #       assert_equal 200, status
  #       assert_equal "/home", path
  #     end
  #   end
  #
  # However, you can also have multiple session instances open per test, and
  # even extend those instances with assertions and methods to create a very
  # powerful testing DSL that is specific for your application. You can even
589
  # reference any named routes you happen to have defined.
590
  #
591
  #   require "test_helper"
592
  #
593
  #   class AdvancedTest < ActionDispatch::IntegrationTest
594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611
  #     fixtures :people, :rooms
  #
  #     def test_login_and_speak
  #       jamis, david = login(:jamis), login(:david)
  #       room = rooms(:office)
  #
  #       jamis.enter(room)
  #       jamis.speak(room, "anybody home?")
  #
  #       david.enter(room)
  #       david.speak(room, "hello!")
  #     end
  #
  #     private
  #
  #       module CustomAssertions
  #         def enter(room)
  #           # reference a named route, for maximum internal consistency!
A
AvnerCohen 已提交
612
  #           get(room_url(id: room.id))
613 614 615 616 617
  #           assert(...)
  #           ...
  #         end
  #
  #         def speak(room, message)
618
  #           post "/say/#{room.id}", xhr: true, params: { message: message }
619 620 621 622 623 624 625 626 627
  #           assert(...)
  #           ...
  #         end
  #       end
  #
  #       def login(who)
  #         open_session do |sess|
  #           sess.extend(CustomAssertions)
  #           who = people(who)
628 629
  #           sess.post "/login", params: { username: who.username,
  #             password: who.password }
630 631 632 633
  #           assert(...)
  #         end
  #       end
  #   end
634 635 636 637 638 639 640 641 642 643 644 645 646 647
  #
  # Another longer example would be:
  #
  # A simple integration test that exercises multiple controllers:
  #
  #   require 'test_helper'
  #
  #   class UserFlowsTest < ActionDispatch::IntegrationTest
  #     test "login and browse site" do
  #       # login via https
  #       https!
  #       get "/login"
  #       assert_response :success
  #
648 649
  #       post "/login", params: { username: users(:david).username, password: users(:david).password }
  #       follow_redirect!
650 651 652 653 654 655
  #       assert_equal '/welcome', path
  #       assert_equal 'Welcome david!', flash[:notice]
  #
  #       https!(false)
  #       get "/articles/all"
  #       assert_response :success
656
  #       assert_select 'h1', 'Articles'
657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694
  #     end
  #   end
  #
  # As you can see the integration test involves multiple controllers and
  # exercises the entire stack from database to dispatcher. In addition you can
  # have multiple session instances open simultaneously in a test and extend
  # those instances with assertion methods to create a very powerful testing
  # DSL (domain-specific language) just for your application.
  #
  # Here's an example of multiple sessions and custom DSL in an integration test
  #
  #   require 'test_helper'
  #
  #   class UserFlowsTest < ActionDispatch::IntegrationTest
  #     test "login and browse site" do
  #       # User david logs in
  #       david = login(:david)
  #       # User guest logs in
  #       guest = login(:guest)
  #
  #       # Both are now available in different sessions
  #       assert_equal 'Welcome david!', david.flash[:notice]
  #       assert_equal 'Welcome guest!', guest.flash[:notice]
  #
  #       # User david can browse site
  #       david.browses_site
  #       # User guest can browse site as well
  #       guest.browses_site
  #
  #       # Continue with other assertions
  #     end
  #
  #     private
  #
  #       module CustomDsl
  #         def browses_site
  #           get "/products/all"
  #           assert_response :success
695
  #           assert_select 'h1', 'Products'
696 697 698 699 700 701 702 703
  #         end
  #       end
  #
  #       def login(user)
  #         open_session do |sess|
  #           sess.extend(CustomDsl)
  #           u = users(user)
  #           sess.https!
704
  #           sess.post "/login", params: { username: u.username, password: u.password }
705 706 707 708 709 710
  #           assert_equal '/welcome', sess.path
  #           sess.https!(false)
  #         end
  #       end
  #   end
  #
711 712 713 714 715 716
  # You can also test your JSON API easily by setting what the request should
  # be encoded as:
  #
  #   require 'test_helper'
  #
  #   class ApiTest < ActionDispatch::IntegrationTest
717
  #     test 'creates articles' do
718 719 720 721 722
  #       assert_difference -> { Article.count } do
  #         post articles_path, params: { article: { title: 'Ahoy!' } }, as: :json
  #       end
  #
  #       assert_response :success
723
  #       assert_equal({ id: Arcticle.last.id, title: 'Ahoy!' }, response.parsed_body)
724 725 726 727 728 729
  #     end
  #   end
  #
  # The `as` option sets the format to JSON, sets the content type to
  # 'application/json' and encodes the parameters as JSON.
  #
730 731 732 733
  # Calling `parsed_body` on the response parses the response body as what
  # the last request was encoded as. If the request wasn't encoded `as` something,
  # it's the same as calling `body`.
  #
734 735
  # For any custom MIME Types you've registered, you can even add your own encoders with:
  #
736 737 738 739 740
  #   ActionDispatch::IntegrationTest.register_encoder :wibble,
  #     param_encoder: -> params { params.to_wibble },
  #     response_parser: -> body { body }
  #
  # Where `param_encoder` defines how the params should be encoded and
741 742
  # `response_parser` defines how the response body should be parsed through
  # `parsed_body`.
743
  #
744 745
  # Consult the Rails Testing Guide for more.

746
  class IntegrationTest < ActiveSupport::TestCase
747
    include Integration::Runner
748
    include ActionController::TemplateAssertions
749
    include ActionDispatch::Routing::UrlFor
750 751 752 753

    @@app = nil

    def self.app
754
      @@app || ActionDispatch.test_app
755 756 757 758 759 760 761 762 763
    end

    def self.app=(app)
      @@app = app
    end

    def app
      super || self.class.app
    end
764 765 766 767

    def url_options
      integration_session.url_options
    end
768 769

    def document_root_element
770
      html_document.root
771
    end
772

773 774
    def self.register_encoder(*args)
      Integration::Session::RequestEncoder.register_encoder(*args)
775
    end
776
  end
777
end