aboutsummaryrefslogtreecommitdiffstats
path: root/activerecord/lib/active_record/fixtures.rb
blob: bad6542be20b74caaa6cd0e742887f419fad5f0f (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
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
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
require "erb"
require "yaml"
require "zlib"
require "set"
require "active_support/dependencies"
require "active_support/core_ext/digest/uuid"
require "active_record/fixture_set/file"
require "active_record/errors"

module ActiveRecord
  class FixtureClassNotFound < ActiveRecord::ActiveRecordError #:nodoc:
  end

  # \Fixtures are a way of organizing data that you want to test against; in short, sample data.
  #
  # They are stored in YAML files, one file per model, which are placed in the directory
  # appointed by <tt>ActiveSupport::TestCase.fixture_path=(path)</tt> (this is automatically
  # configured for Rails, so you can just put your files in <tt><your-rails-app>/test/fixtures/</tt>).
  # The fixture file ends with the +.yml+ file extension, for example:
  # <tt><your-rails-app>/test/fixtures/web_sites.yml</tt>).
  #
  # The format of a fixture file looks like this:
  #
  #   rubyonrails:
  #     id: 1
  #     name: Ruby on Rails
  #     url: http://www.rubyonrails.org
  #
  #   google:
  #     id: 2
  #     name: Google
  #     url: http://www.google.com
  #
  # This fixture file includes two fixtures. Each YAML fixture (ie. record) is given a name and
  # is followed by an indented list of key/value pairs in the "key: value" format. Records are
  # separated by a blank line for your viewing pleasure.
  #
  # Note: Fixtures are unordered. If you want ordered fixtures, use the omap YAML type.
  # See http://yaml.org/type/omap.html
  # for the specification. You will need ordered fixtures when you have foreign key constraints
  # on keys in the same table. This is commonly needed for tree structures. Example:
  #
  #    --- !omap
  #    - parent:
  #        id:         1
  #        parent_id:  NULL
  #        title:      Parent
  #    - child:
  #        id:         2
  #        parent_id:  1
  #        title:      Child
  #
  # = Using Fixtures in Test Cases
  #
  # Since fixtures are a testing construct, we use them in our unit and functional tests. There
  # are two ways to use the fixtures, but first let's take a look at a sample unit test:
  #
  #   require 'test_helper'
  #
  #   class WebSiteTest < ActiveSupport::TestCase
  #     test "web_site_count" do
  #       assert_equal 2, WebSite.count
  #     end
  #   end
  #
  # By default, +test_helper.rb+ will load all of your fixtures into your test
  # database, so this test will succeed.
  #
  # The testing environment will automatically load all the fixtures into the database before each
  # test. To ensure consistent data, the environment deletes the fixtures before running the load.
  #
  # In addition to being available in the database, the fixture's data may also be accessed by
  # using a special dynamic method, which has the same name as the model.
  #
  # Passing in a fixture name to this dynamic method returns the fixture matching this name:
  #
  #   test "find one" do
  #     assert_equal "Ruby on Rails", web_sites(:rubyonrails).name
  #   end
  #
  # Passing in multiple fixture names returns all fixtures matching these names:
  #
  #   test "find all by name" do
  #     assert_equal 2, web_sites(:rubyonrails, :google).length
  #   end
  #
  # Passing in no arguments returns all fixtures:
  #
  #   test "find all" do
  #     assert_equal 2, web_sites.length
  #   end
  #
  # Passing in any fixture name that does not exist will raise <tt>StandardError</tt>:
  #
  #   test "find by name that does not exist" do
  #     assert_raise(StandardError) { web_sites(:reddit) }
  #   end
  #
  # Alternatively, you may enable auto-instantiation of the fixture data. For instance, take the
  # following tests:
  #
  #   test "find_alt_method_1" do
  #     assert_equal "Ruby on Rails", @web_sites['rubyonrails']['name']
  #   end
  #
  #   test "find_alt_method_2" do
  #     assert_equal "Ruby on Rails", @rubyonrails.name
  #   end
  #
  # In order to use these methods to access fixtured data within your test cases, you must specify one of the
  # following in your ActiveSupport::TestCase-derived class:
  #
  # - to fully enable instantiated fixtures (enable alternate methods #1 and #2 above)
  #     self.use_instantiated_fixtures = true
  #
  # - create only the hash for the fixtures, do not 'find' each instance (enable alternate method #1 only)
  #     self.use_instantiated_fixtures = :no_instances
  #
  # Using either of these alternate methods incurs a performance hit, as the fixtured data must be fully
  # traversed in the database to create the fixture hash and/or instance variables. This is expensive for
  # large sets of fixtured data.
  #
  # = Dynamic fixtures with ERB
  #
  # Sometimes you don't care about the content of the fixtures as much as you care about the volume.
  # In these cases, you can mix ERB in with your YAML fixtures to create a bunch of fixtures for load
  # testing, like:
  #
  #   <% 1.upto(1000) do |i| %>
  #   fix_<%= i %>:
  #     id: <%= i %>
  #     name: guy_<%= i %>
  #   <% end %>
  #
  # This will create 1000 very simple fixtures.
  #
  # Using ERB, you can also inject dynamic values into your fixtures with inserts like
  # <tt><%= Date.today.strftime("%Y-%m-%d") %></tt>.
  # This is however a feature to be used with some caution. The point of fixtures are that they're
  # stable units of predictable sample data. If you feel that you need to inject dynamic values, then
  # perhaps you should reexamine whether your application is properly testable. Hence, dynamic values
  # in fixtures are to be considered a code smell.
  #
  # Helper methods defined in a fixture will not be available in other fixtures, to prevent against
  # unwanted inter-test dependencies. Methods used by multiple fixtures should be defined in a module
  # that is included in ActiveRecord::FixtureSet.context_class.
  #
  # - define a helper method in `test_helper.rb`
  #     module FixtureFileHelpers
  #       def file_sha(path)
  #         Digest::SHA2.hexdigest(File.read(Rails.root.join('test/fixtures', path)))
  #       end
  #     end
  #     ActiveRecord::FixtureSet.context_class.include FixtureFileHelpers
  #
  # - use the helper method in a fixture
  #     photo:
  #       name: kitten.png
  #       sha: <%= file_sha 'files/kitten.png' %>
  #
  # = Transactional Tests
  #
  # Test cases can use begin+rollback to isolate their changes to the database instead of having to
  # delete+insert for every test case.
  #
  #   class FooTest < ActiveSupport::TestCase
  #     self.use_transactional_tests = true
  #
  #     test "godzilla" do
  #       assert !Foo.all.empty?
  #       Foo.destroy_all
  #       assert Foo.all.empty?
  #     end
  #
  #     test "godzilla aftermath" do
  #       assert !Foo.all.empty?
  #     end
  #   end
  #
  # If you preload your test database with all fixture data (probably in the rake task) and use
  # transactional tests, then you may omit all fixtures declarations in your test cases since
  # all the data's already there and every case rolls back its changes.
  #
  # In order to use instantiated fixtures with preloaded data, set +self.pre_loaded_fixtures+ to
  # true. This will provide access to fixture data for every table that has been loaded through
  # fixtures (depending on the value of +use_instantiated_fixtures+).
  #
  # When *not* to use transactional tests:
  #
  # 1. You're testing whether a transaction works correctly. Nested transactions don't commit until
  #    all parent transactions commit, particularly, the fixtures transaction which is begun in setup
  #    and rolled back in teardown. Thus, you won't be able to verify
  #    the results of your transaction until Active Record supports nested transactions or savepoints (in progress).
  # 2. Your database does not support transactions. Every Active Record database supports transactions except MySQL MyISAM.
  #    Use InnoDB, MaxDB, or NDB instead.
  #
  # = Advanced Fixtures
  #
  # Fixtures that don't specify an ID get some extra features:
  #
  # * Stable, autogenerated IDs
  # * Label references for associations (belongs_to, has_one, has_many)
  # * HABTM associations as inline lists
  #
  # There are some more advanced features available even if the id is specified:
  #
  # * Autofilled timestamp columns
  # * Fixture label interpolation
  # * Support for YAML defaults
  #
  # == Stable, Autogenerated IDs
  #
  # Here, have a monkey fixture:
  #
  #   george:
  #     id: 1
  #     name: George the Monkey
  #
  #   reginald:
  #     id: 2
  #     name: Reginald the Pirate
  #
  # Each of these fixtures has two unique identifiers: one for the database
  # and one for the humans. Why don't we generate the primary key instead?
  # Hashing each fixture's label yields a consistent ID:
  #
  #   george: # generated id: 503576764
  #     name: George the Monkey
  #
  #   reginald: # generated id: 324201669
  #     name: Reginald the Pirate
  #
  # Active Record looks at the fixture's model class, discovers the correct
  # primary key, and generates it right before inserting the fixture
  # into the database.
  #
  # The generated ID for a given label is constant, so we can discover
  # any fixture's ID without loading anything, as long as we know the label.
  #
  # == Label references for associations (belongs_to, has_one, has_many)
  #
  # Specifying foreign keys in fixtures can be very fragile, not to
  # mention difficult to read. Since Active Record can figure out the ID of
  # any fixture from its label, you can specify FK's by label instead of ID.
  #
  # === belongs_to
  #
  # Let's break out some more monkeys and pirates.
  #
  #   ### in pirates.yml
  #
  #   reginald:
  #     id: 1
  #     name: Reginald the Pirate
  #     monkey_id: 1
  #
  #   ### in monkeys.yml
  #
  #   george:
  #     id: 1
  #     name: George the Monkey
  #     pirate_id: 1
  #
  # Add a few more monkeys and pirates and break this into multiple files,
  # and it gets pretty hard to keep track of what's going on. Let's
  # use labels instead of IDs:
  #
  #   ### in pirates.yml
  #
  #   reginald:
  #     name: Reginald the Pirate
  #     monkey: george
  #
  #   ### in monkeys.yml
  #
  #   george:
  #     name: George the Monkey
  #     pirate: reginald
  #
  # Pow! All is made clear. Active Record reflects on the fixture's model class,
  # finds all the +belongs_to+ associations, and allows you to specify
  # a target *label* for the *association* (monkey: george) rather than
  # a target *id* for the *FK* (<tt>monkey_id: 1</tt>).
  #
  # ==== Polymorphic belongs_to
  #
  # Supporting polymorphic relationships is a little bit more complicated, since
  # Active Record needs to know what type your association is pointing at. Something
  # like this should look familiar:
  #
  #   ### in fruit.rb
  #
  #   belongs_to :eater, polymorphic: true
  #
  #   ### in fruits.yml
  #
  #   apple:
  #     id: 1
  #     name: apple
  #     eater_id: 1
  #     eater_type: Monkey
  #
  # Can we do better? You bet!
  #
  #   apple:
  #     eater: george (Monkey)
  #
  # Just provide the polymorphic target type and Active Record will take care of the rest.
  #
  # === has_and_belongs_to_many
  #
  # Time to give our monkey some fruit.
  #
  #   ### in monkeys.yml
  #
  #   george:
  #     id: 1
  #     name: George the Monkey
  #
  #   ### in fruits.yml
  #
  #   apple:
  #     id: 1
  #     name: apple
  #
  #   orange:
  #     id: 2
  #     name: orange
  #
  #   grape:
  #     id: 3
  #     name: grape
  #
  #   ### in fruits_monkeys.yml
  #
  #   apple_george:
  #     fruit_id: 1
  #     monkey_id: 1
  #
  #   orange_george:
  #     fruit_id: 2
  #     monkey_id: 1
  #
  #   grape_george:
  #     fruit_id: 3
  #     monkey_id: 1
  #
  # Let's make the HABTM fixture go away.
  #
  #   ### in monkeys.yml
  #
  #   george:
  #     id: 1
  #     name: George the Monkey
  #     fruits: apple, orange, grape
  #
  #   ### in fruits.yml
  #
  #   apple:
  #     name: apple
  #
  #   orange:
  #     name: orange
  #
  #   grape:
  #     name: grape
  #
  # Zap! No more fruits_monkeys.yml file. We've specified the list of fruits
  # on George's fixture, but we could've just as easily specified a list
  # of monkeys on each fruit. As with +belongs_to+, Active Record reflects on
  # the fixture's model class and discovers the +has_and_belongs_to_many+
  # associations.
  #
  # == Autofilled Timestamp Columns
  #
  # If your table/model specifies any of Active Record's
  # standard timestamp columns (+created_at+, +created_on+, +updated_at+, +updated_on+),
  # they will automatically be set to <tt>Time.now</tt>.
  #
  # If you've set specific values, they'll be left alone.
  #
  # == Fixture label interpolation
  #
  # The label of the current fixture is always available as a column value:
  #
  #   geeksomnia:
  #     name: Geeksomnia's Account
  #     subdomain: $LABEL
  #     email: $LABEL@email.com
  #
  # Also, sometimes (like when porting older join table fixtures) you'll need
  # to be able to get a hold of the identifier for a given label. ERB
  # to the rescue:
  #
  #   george_reginald:
  #     monkey_id: <%= ActiveRecord::FixtureSet.identify(:reginald) %>
  #     pirate_id: <%= ActiveRecord::FixtureSet.identify(:george) %>
  #
  # == Support for YAML defaults
  #
  # You can set and reuse defaults in your fixtures YAML file.
  # This is the same technique used in the +database.yml+ file to specify
  # defaults:
  #
  #   DEFAULTS: &DEFAULTS
  #     created_on: <%= 3.weeks.ago.to_s(:db) %>
  #
  #   first:
  #     name: Smurf
  #     <<: *DEFAULTS
  #
  #   second:
  #     name: Fraggle
  #     <<: *DEFAULTS
  #
  # Any fixture labeled "DEFAULTS" is safely ignored.
  #
  # == Configure the fixture model class
  #
  # It's possible to set the fixture's model class directly in the YAML file.
  # This is helpful when fixtures are loaded outside tests and
  # +set_fixture_class+ is not available (e.g.
  # when running <tt>rails db:fixtures:load</tt>).
  #
  #   _fixture:
  #     model_class: User
  #   david:
  #     name: David
  #
  # Any fixtures labeled "_fixture" are safely ignored.
  class FixtureSet
    #--
    # An instance of FixtureSet is normally stored in a single YAML file and
    # possibly in a folder with the same name.
    #++

    MAX_ID = 2**30 - 1

    @@all_cached_fixtures = Hash.new { |h, k| h[k] = {} }

    def self.default_fixture_model_name(fixture_set_name, config = ActiveRecord::Base) # :nodoc:
      config.pluralize_table_names ?
        fixture_set_name.singularize.camelize :
        fixture_set_name.camelize
    end

    def self.default_fixture_table_name(fixture_set_name, config = ActiveRecord::Base) # :nodoc:
      "#{ config.table_name_prefix }"\
      "#{ fixture_set_name.tr('/', '_') }"\
      "#{ config.table_name_suffix }".to_sym
    end

    def self.reset_cache
      @@all_cached_fixtures.clear
    end

    def self.cache_for_connection(connection)
      @@all_cached_fixtures[connection]
    end

    def self.fixture_is_cached?(connection, table_name)
      cache_for_connection(connection)[table_name]
    end

    def self.cached_fixtures(connection, keys_to_fetch = nil)
      if keys_to_fetch
        cache_for_connection(connection).values_at(*keys_to_fetch)
      else
        cache_for_connection(connection).values
      end
    end

    def self.cache_fixtures(connection, fixtures_map)
      cache_for_connection(connection).update(fixtures_map)
    end

    def self.instantiate_fixtures(object, fixture_set, load_instances = true)
      if load_instances
        fixture_set.each do |fixture_name, fixture|
          begin
            object.instance_variable_set "@#{fixture_name}", fixture.find
          rescue FixtureClassNotFound
            nil
          end
        end
      end
    end

    def self.instantiate_all_loaded_fixtures(object, load_instances = true)
      all_loaded_fixtures.each_value do |fixture_set|
        instantiate_fixtures(object, fixture_set, load_instances)
      end
    end

    cattr_accessor :all_loaded_fixtures
    self.all_loaded_fixtures = {}

    class ClassCache
      def initialize(class_names, config)
        @class_names = class_names.stringify_keys
        @config      = config

        # Remove string values that aren't constants or subclasses of AR
        @class_names.delete_if { |klass_name, klass| !insert_class(@class_names, klass_name, klass) }
      end

      def [](fs_name)
        @class_names.fetch(fs_name) {
          klass = default_fixture_model(fs_name, @config).safe_constantize
          insert_class(@class_names, fs_name, klass)
        }
      end

      private

        def insert_class(class_names, name, klass)
          # We only want to deal with AR objects.
          if klass && klass < ActiveRecord::Base
            class_names[name] = klass
          else
            class_names[name] = nil
          end
        end

        def default_fixture_model(fs_name, config)
          ActiveRecord::FixtureSet.default_fixture_model_name(fs_name, config)
        end
    end

    def self.create_fixtures(fixtures_directory, fixture_set_names, class_names = {}, config = ActiveRecord::Base)
      fixture_set_names = Array(fixture_set_names).map(&:to_s)
      class_names = ClassCache.new class_names, config

      # FIXME: Apparently JK uses this.
      connection = block_given? ? yield : ActiveRecord::Base.connection

      files_to_read = fixture_set_names.reject { |fs_name|
        fixture_is_cached?(connection, fs_name)
      }

      unless files_to_read.empty?
        connection.disable_referential_integrity do
          fixtures_map = {}

          fixture_sets = files_to_read.map do |fs_name|
            klass = class_names[fs_name]
            conn = klass ? klass.connection : connection
            fixtures_map[fs_name] = new( # ActiveRecord::FixtureSet.new
              conn,
              fs_name,
              klass,
              ::File.join(fixtures_directory, fs_name))
          end

          update_all_loaded_fixtures fixtures_map

          connection.transaction(requires_new: true) do
            deleted_tables = Hash.new { |h, k| h[k] = Set.new }
            fixture_sets.each do |fs|
              conn = fs.model_class.respond_to?(:connection) ? fs.model_class.connection : connection
              table_rows = fs.table_rows

              table_rows.each_key do |table|
                unless deleted_tables[conn].include? table
                  conn.delete "DELETE FROM #{conn.quote_table_name(table)}", "Fixture Delete"
                end
                deleted_tables[conn] << table
              end

              table_rows.each do |fixture_set_name, rows|
                rows.each do |row|
                  conn.insert_fixture(row, fixture_set_name)
                end
              end

              # Cap primary key sequences to max(pk).
              if conn.respond_to?(:reset_pk_sequence!)
                conn.reset_pk_sequence!(fs.table_name)
              end
            end
          end

          cache_fixtures(connection, fixtures_map)
        end
      end
      cached_fixtures(connection, fixture_set_names)
    end

    # Returns a consistent, platform-independent identifier for +label+.
    # Integer identifiers are values less than 2^30. UUIDs are RFC 4122 version 5 SHA-1 hashes.
    def self.identify(label, column_type = :integer)
      if column_type == :uuid
        Digest::UUID.uuid_v5(Digest::UUID::OID_NAMESPACE, label.to_s)
      else
        Zlib.crc32(label.to_s) % MAX_ID
      end
    end

    # Superclass for the evaluation contexts used by ERB fixtures.
    def self.context_class
      @context_class ||= Class.new
    end

    def self.update_all_loaded_fixtures(fixtures_map) # :nodoc:
      all_loaded_fixtures.update(fixtures_map)
    end

    attr_reader :table_name, :name, :fixtures, :model_class, :config

    def initialize(connection, name, class_name, path, config = ActiveRecord::Base)
      @name     = name
      @path     = path
      @config   = config

      self.model_class = class_name

      @fixtures = read_fixture_files(path)

      @connection = connection

      @table_name = (model_class.respond_to?(:table_name) ?
                      model_class.table_name :
                      self.class.default_fixture_table_name(name, config))
    end

    def [](x)
      fixtures[x]
    end

    def []=(k, v)
      fixtures[k] = v
    end

    def each(&block)
      fixtures.each(&block)
    end

    def size
      fixtures.size
    end

    # Returns a hash of rows to be inserted. The key is the table, the value is
    # a list of rows to insert to that table.
    def table_rows
      now = config.default_timezone == :utc ? Time.now.utc : Time.now

      # allow a standard key to be used for doing defaults in YAML
      fixtures.delete("DEFAULTS")

      # track any join tables we need to insert later
      rows = Hash.new { |h, table| h[table] = [] }

      rows[table_name] = fixtures.map do |label, fixture|
        row = fixture.to_hash

        if model_class
          # fill in timestamp columns if they aren't specified and the model is set to record_timestamps
          if model_class.record_timestamps
            timestamp_column_names.each do |c_name|
              row[c_name] = now unless row.key?(c_name)
            end
          end

          # interpolate the fixture label
          row.each do |key, value|
            row[key] = value.gsub("$LABEL", label.to_s) if value.is_a?(String)
          end

          # generate a primary key if necessary
          if has_primary_key_column? && !row.include?(primary_key_name)
            row[primary_key_name] = ActiveRecord::FixtureSet.identify(label, primary_key_type)
          end

          # Resolve enums
          model_class.defined_enums.each do |name, values|
            if row.include?(name)
              row[name] = values.fetch(row[name], row[name])
            end
          end

          # If STI is used, find the correct subclass for association reflection
          reflection_class =
            if row.include?(inheritance_column_name)
              row[inheritance_column_name].constantize rescue model_class
            else
              model_class
            end

          reflection_class._reflections.each_value do |association|
            case association.macro
            when :belongs_to
              # Do not replace association name with association foreign key if they are named the same
              fk_name = (association.options[:foreign_key] || "#{association.name}_id").to_s

              if association.name.to_s != fk_name && value = row.delete(association.name.to_s)
                if association.polymorphic? && value.sub!(/\s*\(([^\)]*)\)\s*$/, "")
                  # support polymorphic belongs_to as "label (Type)"
                  row[association.foreign_type] = $1
                end

                fk_type = reflection_class.type_for_attribute(fk_name).type
                row[fk_name] = ActiveRecord::FixtureSet.identify(value, fk_type)
              end
            when :has_many
              if association.options[:through]
                add_join_records(rows, row, HasManyThroughProxy.new(association))
              end
            end
          end
        end

        row
      end
      rows
    end

    class ReflectionProxy # :nodoc:
      def initialize(association)
        @association = association
      end

      def join_table
        @association.join_table
      end

      def name
        @association.name
      end

      def primary_key_type
        @association.klass.type_for_attribute(@association.klass.primary_key).type
      end
    end

    class HasManyThroughProxy < ReflectionProxy # :nodoc:
      def rhs_key
        @association.foreign_key
      end

      def lhs_key
        @association.through_reflection.foreign_key
      end

      def join_table
        @association.through_reflection.table_name
      end
    end

    private
      def primary_key_name
        @primary_key_name ||= model_class && model_class.primary_key
      end

      def primary_key_type
        @primary_key_type ||= model_class && model_class.type_for_attribute(model_class.primary_key).type
      end

      def add_join_records(rows, row, association)
        # This is the case when the join table has no fixtures file
        if (targets = row.delete(association.name.to_s))
          table_name  = association.join_table
          column_type = association.primary_key_type
          lhs_key     = association.lhs_key
          rhs_key     = association.rhs_key

          targets = targets.is_a?(Array) ? targets : targets.split(/\s*,\s*/)
          rows[table_name].concat targets.map { |target|
            { lhs_key => row[primary_key_name],
              rhs_key => ActiveRecord::FixtureSet.identify(target, column_type) }
          }
        end
      end

      def has_primary_key_column?
        @has_primary_key_column ||= primary_key_name &&
          model_class.columns.any? { |c| c.name == primary_key_name }
      end

      def timestamp_column_names
        @timestamp_column_names ||=
          %w(created_at created_on updated_at updated_on) & column_names
      end

      def inheritance_column_name
        @inheritance_column_name ||= model_class && model_class.inheritance_column
      end

      def column_names
        @column_names ||= @connection.columns(@table_name).collect(&:name)
      end

      def model_class=(class_name)
        if class_name.is_a?(Class) # TODO: Should be an AR::Base type class, or any?
          @model_class = class_name
        else
          @model_class = class_name.safe_constantize if class_name
        end
      end

      # Loads the fixtures from the YAML file at +path+.
      # If the file sets the +model_class+ and current instance value is not set,
      # it uses the file value.
      def read_fixture_files(path)
        yaml_files = Dir["#{path}/{**,*}/*.yml"].select { |f|
          ::File.file?(f)
        } + [yaml_file_path(path)]

        yaml_files.each_with_object({}) do |file, fixtures|
          FixtureSet::File.open(file) do |fh|
            self.model_class ||= fh.model_class if fh.model_class
            fh.each do |fixture_name, row|
              fixtures[fixture_name] = ActiveRecord::Fixture.new(row, model_class)
            end
          end
        end
      end

      def yaml_file_path(path)
        "#{path}.yml"
      end
  end

  class Fixture #:nodoc:
    include Enumerable

    class FixtureError < StandardError #:nodoc:
    end

    class FormatError < FixtureError #:nodoc:
    end

    attr_reader :model_class, :fixture

    def initialize(fixture, model_class)
      @fixture     = fixture
      @model_class = model_class
    end

    def class_name
      model_class.name if model_class
    end

    def each
      fixture.each { |item| yield item }
    end

    def [](key)
      fixture[key]
    end

    alias :to_hash :fixture

    def find
      if model_class
        model_class.unscoped do
          model_class.find(fixture[model_class.primary_key])
        end
      else
        raise FixtureClassNotFound, "No class attached to find."
      end
    end
  end
end

module ActiveRecord
  module TestFixtures
    extend ActiveSupport::Concern

    def before_setup # :nodoc:
      setup_fixtures
      super
    end

    def after_teardown # :nodoc:
      super
      teardown_fixtures
    end

    included do
      class_attribute :fixture_path, instance_writer: false
      class_attribute :fixture_table_names, default: []
      class_attribute :fixture_class_names, default: {}
      class_attribute :use_transactional_tests, default: true
      class_attribute :use_instantiated_fixtures, default: false # true, false, or :no_instances
      class_attribute :pre_loaded_fixtures, default: false
      class_attribute :config, default: ActiveRecord::Base
    end

    module ClassMethods
      # Sets the model class for a fixture when the class name cannot be inferred from the fixture name.
      #
      # Examples:
      #
      #   set_fixture_class some_fixture:        SomeModel,
      #                     'namespaced/fixture' => Another::Model
      #
      # The keys must be the fixture names, that coincide with the short paths to the fixture files.
      def set_fixture_class(class_names = {})
        self.fixture_class_names = fixture_class_names.merge(class_names.stringify_keys)
      end

      def fixtures(*fixture_set_names)
        if fixture_set_names.first == :all
          fixture_set_names = Dir["#{fixture_path}/{**,*}/*.{yml}"].uniq
          fixture_set_names.map! { |f| f[(fixture_path.to_s.size + 1)..-5] }
        else
          fixture_set_names = fixture_set_names.flatten.map(&:to_s)
        end

        self.fixture_table_names |= fixture_set_names
        setup_fixture_accessors(fixture_set_names)
      end

      def setup_fixture_accessors(fixture_set_names = nil)
        fixture_set_names = Array(fixture_set_names || fixture_table_names)
        methods = Module.new do
          fixture_set_names.each do |fs_name|
            fs_name = fs_name.to_s
            accessor_name = fs_name.tr("/", "_").to_sym

            define_method(accessor_name) do |*fixture_names|
              force_reload = fixture_names.pop if fixture_names.last == true || fixture_names.last == :reload
              return_single_record = fixture_names.size == 1
              fixture_names = @loaded_fixtures[fs_name].fixtures.keys if fixture_names.empty?

              @fixture_cache[fs_name] ||= {}

              instances = fixture_names.map do |f_name|
                f_name = f_name.to_s if f_name.is_a?(Symbol)
                @fixture_cache[fs_name].delete(f_name) if force_reload

                if @loaded_fixtures[fs_name][f_name]
                  @fixture_cache[fs_name][f_name] ||= @loaded_fixtures[fs_name][f_name].find
                else
                  raise StandardError, "No fixture named '#{f_name}' found for fixture set '#{fs_name}'"
                end
              end

              return_single_record ? instances.first : instances
            end
            private accessor_name
          end
        end
        include methods
      end

      def uses_transaction(*methods)
        @uses_transaction = [] unless defined?(@uses_transaction)
        @uses_transaction.concat methods.map(&:to_s)
      end

      def uses_transaction?(method)
        @uses_transaction = [] unless defined?(@uses_transaction)
        @uses_transaction.include?(method.to_s)
      end
    end

    def run_in_transaction?
      use_transactional_tests &&
        !self.class.uses_transaction?(method_name)
    end

    def setup_fixtures(config = ActiveRecord::Base)
      if pre_loaded_fixtures && !use_transactional_tests
        raise RuntimeError, "pre_loaded_fixtures requires use_transactional_tests"
      end

      @fixture_cache = {}
      @fixture_connections = []
      @@already_loaded_fixtures ||= {}
      @connection_subscriber = nil

      # Load fixtures once and begin transaction.
      if run_in_transaction?
        if @@already_loaded_fixtures[self.class]
          @loaded_fixtures = @@already_loaded_fixtures[self.class]
        else
          @loaded_fixtures = load_fixtures(config)
          @@already_loaded_fixtures[self.class] = @loaded_fixtures
        end

        # Begin transactions for connections already established
        @fixture_connections = enlist_fixture_connections
        @fixture_connections.each do |connection|
          connection.begin_transaction joinable: false
          connection.pool.lock_thread = true
        end

        # When connections are established in the future, begin a transaction too
        @connection_subscriber = ActiveSupport::Notifications.subscribe("!connection.active_record") do |_, _, _, _, payload|
          spec_name = payload[:spec_name] if payload.key?(:spec_name)

          if spec_name
            begin
              connection = ActiveRecord::Base.connection_handler.retrieve_connection(spec_name)
            rescue ConnectionNotEstablished
              connection = nil
            end

            if connection && !@fixture_connections.include?(connection)
              connection.begin_transaction joinable: false
              connection.pool.lock_thread = true
              @fixture_connections << connection
            end
          end
        end

      # Load fixtures for every test.
      else
        ActiveRecord::FixtureSet.reset_cache
        @@already_loaded_fixtures[self.class] = nil
        @loaded_fixtures = load_fixtures(config)
      end

      # Instantiate fixtures for every test if requested.
      instantiate_fixtures if use_instantiated_fixtures
    end

    def teardown_fixtures
      # Rollback changes if a transaction is active.
      if run_in_transaction?
        ActiveSupport::Notifications.unsubscribe(@connection_subscriber) if @connection_subscriber
        @fixture_connections.each do |connection|
          connection.rollback_transaction if connection.transaction_open?
          connection.pool.lock_thread = false
        end
        @fixture_connections.clear
      else
        ActiveRecord::FixtureSet.reset_cache
      end

      ActiveRecord::Base.clear_active_connections!
    end

    def enlist_fixture_connections
      ActiveRecord::Base.connection_handler.connection_pool_list.map(&:connection)
    end

    private
      def load_fixtures(config)
        fixtures = ActiveRecord::FixtureSet.create_fixtures(fixture_path, fixture_table_names, fixture_class_names, config)
        Hash[fixtures.map { |f| [f.name, f] }]
      end

      def instantiate_fixtures
        if pre_loaded_fixtures
          raise RuntimeError, "Load fixtures before instantiating them." if ActiveRecord::FixtureSet.all_loaded_fixtures.empty?
          ActiveRecord::FixtureSet.instantiate_all_loaded_fixtures(self, load_instances?)
        else
          raise RuntimeError, "Load fixtures before instantiating them." if @loaded_fixtures.nil?
          @loaded_fixtures.each_value do |fixture_set|
            ActiveRecord::FixtureSet.instantiate_fixtures(self, fixture_set, load_instances?)
          end
        end
      end

      def load_instances?
        use_instantiated_fixtures != :no_instances
      end
  end
end

class ActiveRecord::FixtureSet::RenderContext # :nodoc:
  def self.create_subclass
    Class.new ActiveRecord::FixtureSet.context_class do
      def get_binding
        binding()
      end
    end
  end
end