aboutsummaryrefslogtreecommitdiffstats
path: root/activesupport/test/core_ext/module_test.rb
blob: 283b13ff8b937af489490986bbab462046024caa (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
require 'abstract_unit'
require 'active_support/core_ext/module'

module One
  Constant1 = "Hello World"
  Constant2 = "What's up?"
end

class Ab
  include One
  Constant1 = "Hello World" # Will have different object id than One::Constant1
  Constant3 = "Goodbye World"
end

module Xy
  class Bc
    include One
  end
end

module Yz
  module Zy
    class Cd
      include One
    end
  end
end

Somewhere = Struct.new(:street, :city) do
  attr_accessor :name
end

class Someone < Struct.new(:name, :place)
  delegate :street, :city, :to_f, :to => :place
  delegate :name=, :to => :place, :prefix => true
  delegate :upcase, :to => "place.city"
  delegate :table_name, :to => :class
  delegate :table_name, :to => :class, :prefix => true

  def self.table_name
    'some_table'
  end

  FAILED_DELEGATE_LINE = __LINE__ + 1
  delegate :foo, :to => :place

  FAILED_DELEGATE_LINE_2 = __LINE__ + 1
  delegate :bar, :to => :place, :allow_nil => true
end

Invoice   = Struct.new(:client) do
  delegate :street, :city, :name, :to => :client, :prefix => true
  delegate :street, :city, :name, :to => :client, :prefix => :customer
end

Project   = Struct.new(:description, :person) do
  delegate :name, :to => :person, :allow_nil => true
  delegate :to_f, :to => :description, :allow_nil => true
end

Developer = Struct.new(:client) do
  delegate :name, :to => :client, :prefix => nil
end

Tester = Struct.new(:client) do
  delegate :name, :to => :client, :prefix => false
end

Product = Struct.new(:name) do
  delegate :name, :to => :manufacturer, :prefix => true
  delegate :name, :to => :type, :prefix => true

  def manufacturer
    @manufacturer ||= begin
      nil.unknown_method
    end
  end

  def type
    @type ||= begin
      nil.type_name
    end
  end
end

class ParameterSet
  delegate :[], :[]=, :to => :@params

  def initialize
    @params = {:foo => "bar"}
  end
end

class Name
  delegate :upcase, :to => :@full_name

  def initialize(first, last)
    @full_name = "#{first} #{last}"
  end
end

class SideEffect
  attr_reader :ints

  delegate :to_i, :to => :shift, :allow_nil => true
  delegate :to_s, :to => :shift

  def initialize
    @ints = [1, 2, 3]
  end

  def shift
    @ints.shift
  end
end

class ModuleTest < ActiveSupport::TestCase
  def setup
    @david = Someone.new("David", Somewhere.new("Paulina", "Chicago"))
  end

  def test_delegation_to_methods
    assert_equal "Paulina", @david.street
    assert_equal "Chicago", @david.city
  end

  def test_delegation_to_assignment_method
    @david.place_name = "Fred"
    assert_equal "Fred", @david.place.name
  end

  def test_delegation_to_index_get_method
    @params = ParameterSet.new
    assert_equal "bar", @params[:foo]
  end

  def test_delegation_to_index_set_method
    @params = ParameterSet.new
    @params[:foo] = "baz"
    assert_equal "baz", @params[:foo]
  end

  def test_delegation_down_hierarchy
    assert_equal "CHICAGO", @david.upcase
  end

  def test_delegation_to_instance_variable
    david = Name.new("David", "Hansson")
    assert_equal "DAVID HANSSON", david.upcase
  end

  def test_delegation_to_class_method
    assert_equal 'some_table', @david.table_name
    assert_equal 'some_table', @david.class_table_name
  end

  def test_missing_delegation_target
    assert_raise(ArgumentError) do
      Name.send :delegate, :nowhere
    end
    assert_raise(ArgumentError) do
      Name.send :delegate, :noplace, :tos => :hollywood
    end
  end

  def test_delegation_prefix
    invoice = Invoice.new(@david)
    assert_equal invoice.client_name, "David"
    assert_equal invoice.client_street, "Paulina"
    assert_equal invoice.client_city, "Chicago"
  end

  def test_delegation_custom_prefix
    invoice = Invoice.new(@david)
    assert_equal invoice.customer_name, "David"
    assert_equal invoice.customer_street, "Paulina"
    assert_equal invoice.customer_city, "Chicago"
  end

  def test_delegation_prefix_with_nil_or_false
    assert_equal Developer.new(@david).name, "David"
    assert_equal Tester.new(@david).name, "David"
  end

  def test_delegation_prefix_with_instance_variable
    assert_raise ArgumentError do
      Class.new do
        def initialize(client)
          @client = client
        end
        delegate :name, :address, :to => :@client, :prefix => true
      end
    end
  end

  def test_delegation_with_allow_nil
    rails = Project.new("Rails", Someone.new("David"))
    assert_equal rails.name, "David"
  end

  def test_delegation_with_allow_nil_and_nil_value
    rails = Project.new("Rails")
    assert_nil rails.name
  end

  # Ensures with check for nil, not for a falseish target.
  def test_delegation_with_allow_nil_and_false_value
    project = Project.new(false, false)
    assert_raise(NoMethodError) { project.name }
  end

  def test_delegation_with_allow_nil_and_invalid_value
    rails = Project.new("Rails", "David")
    assert_raise(NoMethodError) { rails.name }
  end

  def test_delegation_with_allow_nil_and_nil_value_and_prefix
    Project.class_eval do
      delegate :name, :to => :person, :allow_nil => true, :prefix => true
    end
    rails = Project.new("Rails")
    assert_nil rails.person_name
  end

  def test_delegation_without_allow_nil_and_nil_value
    david = Someone.new("David")
    assert_raise(Module::DelegationError) { david.street }
  end

  def test_delegation_to_method_that_exists_on_nil
    nil_person = Someone.new(nil)
    assert_equal 0.0, nil_person.to_f
  end

  def test_delegation_to_method_that_exists_on_nil_when_allowing_nil
    nil_project = Project.new(nil)
    assert_equal 0.0, nil_project.to_f
  end

  def test_delegation_does_not_raise_error_when_removing_singleton_instance_methods
    parent = Class.new do
      def self.parent_method; end
    end

    assert_nothing_raised do
      Class.new(parent) do
        class << self
          delegate :parent_method, :to => :superclass
        end
      end
    end
  end

  def test_delegation_exception_backtrace
    someone = Someone.new("foo", "bar")
    someone.foo
  rescue NoMethodError => e
    file_and_line = "#{__FILE__}:#{Someone::FAILED_DELEGATE_LINE}"
    # We can't simply check the first line of the backtrace, because JRuby reports the call to __send__ in the backtrace.
    assert e.backtrace.any?{|a| a.include?(file_and_line)},
           "[#{e.backtrace.inspect}] did not include [#{file_and_line}]"
  end

  def test_delegation_exception_backtrace_with_allow_nil
    someone = Someone.new("foo", "bar")
    someone.bar
  rescue NoMethodError => e
    file_and_line = "#{__FILE__}:#{Someone::FAILED_DELEGATE_LINE_2}"
    # We can't simply check the first line of the backtrace, because JRuby reports the call to __send__ in the backtrace.
    assert e.backtrace.any?{|a| a.include?(file_and_line)},
           "[#{e.backtrace.inspect}] did not include [#{file_and_line}]"
  end

  def test_delegation_invokes_the_target_exactly_once
    se = SideEffect.new

    assert_equal 1, se.to_i
    assert_equal [2, 3], se.ints

    assert_equal '2', se.to_s
    assert_equal [3], se.ints
  end

  def test_delegation_doesnt_mask_nested_no_method_error_on_nil_receiver
    product = Product.new('Widget')

    # Nested NoMethodError is a different name from the delegation
    assert_raise(NoMethodError) { product.manufacturer_name }

    # Nested NoMethodError is the same name as the delegation
    assert_raise(NoMethodError) { product.type_name }
  end

  def test_parent
    assert_equal Yz::Zy, Yz::Zy::Cd.parent
    assert_equal Yz, Yz::Zy.parent
    assert_equal Object, Yz.parent
  end

  def test_parents
    assert_equal [Yz::Zy, Yz, Object], Yz::Zy::Cd.parents
    assert_equal [Yz, Object], Yz::Zy.parents
  end

  def test_local_constants
    assert_equal %w(Constant1 Constant3), Ab.local_constants.sort.map(&:to_s)
  end
end

module BarMethodAliaser
  def self.included(foo_class)
    foo_class.class_eval do
      include BarMethods
      alias_method_chain :bar, :baz
    end
  end
end

module BarMethods
  def bar_with_baz
    bar_without_baz << '_with_baz'
  end

  def quux_with_baz!
    quux_without_baz! << '_with_baz'
  end

  def quux_with_baz?
    false
  end

  def quux_with_baz=(v)
    send(:quux_without_baz=, v) << '_with_baz'
  end

  def duck_with_orange
    duck_without_orange << '_with_orange'
  end
end

class MethodAliasingTest < ActiveSupport::TestCase
  def setup
    Object.const_set :FooClassWithBarMethod, Class.new { def bar() 'bar' end }
    @instance = FooClassWithBarMethod.new
  end

  def teardown
    Object.instance_eval { remove_const :FooClassWithBarMethod }
  end

  def test_alias_method_chain
    assert @instance.respond_to?(:bar)
    feature_aliases = [:bar_with_baz, :bar_without_baz]

    feature_aliases.each do |method|
      assert !@instance.respond_to?(method)
    end

    assert_equal 'bar', @instance.bar

    FooClassWithBarMethod.class_eval { include BarMethodAliaser }

    feature_aliases.each do |method|
      assert_respond_to @instance, method
    end

    assert_equal 'bar_with_baz', @instance.bar
    assert_equal 'bar', @instance.bar_without_baz
  end

  def test_alias_method_chain_with_punctuation_method
    FooClassWithBarMethod.class_eval do
      def quux!; 'quux' end
    end

    assert !@instance.respond_to?(:quux_with_baz!)
    FooClassWithBarMethod.class_eval do
      include BarMethodAliaser
      alias_method_chain :quux!, :baz
    end
    assert_respond_to @instance, :quux_with_baz!

    assert_equal 'quux_with_baz', @instance.quux!
    assert_equal 'quux', @instance.quux_without_baz!
  end

  def test_alias_method_chain_with_same_names_between_predicates_and_bang_methods
    FooClassWithBarMethod.class_eval do
      def quux!; 'quux!' end
      def quux?; true end
      def quux=(v); 'quux=' end
    end

    assert !@instance.respond_to?(:quux_with_baz!)
    assert !@instance.respond_to?(:quux_with_baz?)
    assert !@instance.respond_to?(:quux_with_baz=)

    FooClassWithBarMethod.class_eval { include BarMethodAliaser }
    assert_respond_to @instance, :quux_with_baz!
    assert_respond_to @instance, :quux_with_baz?
    assert_respond_to @instance, :quux_with_baz=


    FooClassWithBarMethod.alias_method_chain :quux!, :baz
    assert_equal 'quux!_with_baz', @instance.quux!
    assert_equal 'quux!', @instance.quux_without_baz!

    FooClassWithBarMethod.alias_method_chain :quux?, :baz
    assert_equal false, @instance.quux?
    assert_equal true,  @instance.quux_without_baz?

    FooClassWithBarMethod.alias_method_chain :quux=, :baz
    assert_equal 'quux=_with_baz', @instance.send(:quux=, 1234)
    assert_equal 'quux=', @instance.send(:quux_without_baz=, 1234)
  end

  def test_alias_method_chain_with_feature_punctuation
    FooClassWithBarMethod.class_eval do
      def quux; 'quux' end
      def quux?; 'quux?' end
      include BarMethodAliaser
      alias_method_chain :quux, :baz!
    end

    assert_nothing_raised do
      assert_equal 'quux_with_baz', @instance.quux_with_baz!
    end

    assert_raise(NameError) do
      FooClassWithBarMethod.alias_method_chain :quux?, :baz!
    end
  end

  def test_alias_method_chain_yields_target_and_punctuation
    args = nil

    FooClassWithBarMethod.class_eval do
      def quux?; end
      include BarMethods

      FooClassWithBarMethod.alias_method_chain :quux?, :baz do |target, punctuation|
        args = [target, punctuation]
      end
    end

    assert_not_nil args
    assert_equal 'quux', args[0]
    assert_equal '?', args[1]
  end

  def test_alias_method_chain_preserves_private_method_status
    FooClassWithBarMethod.class_eval do
      def duck; 'duck' end
      include BarMethodAliaser
      private :duck
      alias_method_chain :duck, :orange
    end

    assert_raise NoMethodError do
      @instance.duck
    end

    assert_equal 'duck_with_orange', @instance.instance_eval { duck }
    assert FooClassWithBarMethod.private_method_defined?(:duck)
  end

  def test_alias_method_chain_preserves_protected_method_status
    FooClassWithBarMethod.class_eval do
      def duck; 'duck' end
      include BarMethodAliaser
      protected :duck
      alias_method_chain :duck, :orange
    end

    assert_raise NoMethodError do
      @instance.duck
    end

    assert_equal 'duck_with_orange', @instance.instance_eval { duck }
    assert FooClassWithBarMethod.protected_method_defined?(:duck)
  end

  def test_alias_method_chain_preserves_public_method_status
    FooClassWithBarMethod.class_eval do
      def duck; 'duck' end
      include BarMethodAliaser
      public :duck
      alias_method_chain :duck, :orange
    end

    assert_equal 'duck_with_orange', @instance.duck
    assert FooClassWithBarMethod.public_method_defined?(:duck)
  end
end