File: test_deep_merge.rb

package info (click to toggle)
ruby-deep-merge 1.1.1-1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye, buster, sid, stretch
  • size: 144 kB
  • ctags: 23
  • sloc: ruby: 612; makefile: 2
file content (626 lines) | stat: -rw-r--r-- 38,878 bytes parent folder | download | duplicates (2)
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
require 'test/unit'

$:.unshift(File.dirname(__FILE__) + '/../lib/')
require 'deep_merge'

# Assume strings have a blank? method
# as they do when ActiveSupport is included.
module StringBlank
  def blank?
    size == 0
  end
end

class TestDeepMerge < Test::Unit::TestCase

  def setup
  end

  # show that Hash object has deep merge capabilities in form of three methods:
  #   ko_deep_merge! # uses '--' knockout and overwrites unmergeable
  #   deep_merge! # overwrites unmergeable
  #   deep_merge # skips unmergeable
  def test_hash_deep_merge
    x = {}
    assert x.respond_to?('deep_merge!'.to_sym)
    hash_src  = {'id' => [3,4,5]}
    hash_dest = {'id' => [1,2,3]}
    assert hash_dest.ko_deep_merge!(hash_src)
    assert_equal({'id' => [1,2,3,4,5]}, hash_dest)

    hash_src  = {'id' => [3,4,5]}
    hash_dest = {'id' => [1,2,3]}
    assert hash_dest.deep_merge!(hash_src)
    assert_equal({'id' => [1,2,3,4,5]}, hash_dest)

    hash_src  = {'id' => 'xxx'}
    hash_dest = {'id' => [1,2,3]}
    assert hash_dest.deep_merge(hash_src)
    assert_equal({'id' => [1,2,3]}, hash_dest)
  end

  FIELD_KNOCKOUT_PREFIX = DeepMerge::DEFAULT_FIELD_KNOCKOUT_PREFIX

  # tests DeepMerge::deep_merge! function
  def test_deep_merge
    # merge tests (moving from basic to more complex)

    # test merging an hash w/array into blank hash
    hash_src = {'id' => '2'}
    hash_dst = {}
    DeepMerge::deep_merge!(hash_src.dup, hash_dst, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal hash_src, hash_dst

    # test merging an hash w/array into blank hash
    hash_src = {'region' => {'id' => ['227', '2']}}
    hash_dst = {}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal hash_src, hash_dst

    # merge from empty hash
    hash_src = {}
    hash_dst = {"property" => ["2","4"]}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => ["2","4"]}, hash_dst)

    # merge to empty hash
    hash_src = {"property" => ["2","4"]}
    hash_dst = {}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => ["2","4"]}, hash_dst)

    # simple string overwrite
    hash_src = {"name" => "value"}
    hash_dst = {"name" => "value1"}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"name" => "value"}, hash_dst)

    # simple string overwrite of empty hash
    hash_src = {"name" => "value"}
    hash_dst = {}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal(hash_src, hash_dst)

    # hashes holding array
    hash_src = {"property" => ["1","3"]}
    hash_dst = {"property" => ["2","4"]}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal(["2","4","1","3"], hash_dst['property'])

    # hashes holding array (overwrite)
    hash_src = {"property" => ["1","3"]}
    hash_dst = {"property" => ["2","4"]}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:overwrite_arrays => true})
    assert_equal(["1","3"], hash_dst['property'])

    # hashes holding array (sorted)
    hash_src = {"property" => ["1","3"]}
    hash_dst = {"property" => ["2","4"]}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:sort_merged_arrays => true})
    assert_equal(["1","2","3","4"].sort, hash_dst['property'])

    # hashes holding hashes holding arrays (array with duplicate elements is merged with dest then src
    hash_src = {"property" => {"bedroom_count" => ["1", "2"], "bathroom_count" => ["1", "4+"]}}
    hash_dst = {"property" => {"bedroom_count" => ["3", "2"], "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => ["3","2","1"], "bathroom_count" => ["2", "1", "4+"]}}, hash_dst)

    # hash holding hash holding array v string (string is overwritten by array)
    hash_src = {"property" => {"bedroom_count" => ["1", "2"], "bathroom_count" => ["1", "4+"]}}
    hash_dst = {"property" => {"bedroom_count" => "3", "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => ["1", "2"], "bathroom_count" => ["2","1","4+"]}}, hash_dst)

    # hash holding hash holding array v string (string is NOT overwritten by array)
    hash_src = {"property" => {"bedroom_count" => ["1", "2"], "bathroom_count" => ["1", "4+"]}}
    hash_dst = {"property" => {"bedroom_count" => "3", "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:preserve_unmergeables => true})
    assert_equal({"property" => {"bedroom_count" => "3", "bathroom_count" => ["2","1","4+"]}}, hash_dst)

    # hash holding hash holding string v array (array is overwritten by string)
    hash_src = {"property" => {"bedroom_count" => "3", "bathroom_count" => ["1", "4+"]}}
    hash_dst = {"property" => {"bedroom_count" => ["1", "2"], "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => "3", "bathroom_count" => ["2","1","4+"]}}, hash_dst)

    # hash holding hash holding string v array (array does NOT overwrite string)
    hash_src = {"property" => {"bedroom_count" => "3", "bathroom_count" => ["1", "4+"]}}
    hash_dst = {"property" => {"bedroom_count" => ["1", "2"], "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:preserve_unmergeables => true})
    assert_equal({"property" => {"bedroom_count" => ["1", "2"], "bathroom_count" => ["2","1","4+"]}}, hash_dst)

    # hash holding hash holding hash v array (array is overwritten by hash)
    hash_src = {"property" => {"bedroom_count" => {"king_bed" => 3, "queen_bed" => 1}, "bathroom_count" => ["1", "4+"]}}
    hash_dst = {"property" => {"bedroom_count" => ["1", "2"], "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => {"king_bed" => 3, "queen_bed" => 1}, "bathroom_count" => ["2","1","4+"]}}, hash_dst)

    # hash holding hash holding hash v array (array is NOT overwritten by hash)
    hash_src = {"property" => {"bedroom_count" => {"king_bed" => 3, "queen_bed" => 1}, "bathroom_count" => ["1", "4+"]}}
    hash_dst = {"property" => {"bedroom_count" => ["1", "2"], "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:preserve_unmergeables => true})
    assert_equal({"property" => {"bedroom_count" => ["1", "2"], "bathroom_count" => ["2","1","4+"]}}, hash_dst)

    # 3 hash layers holding integers (integers are overwritten by source)
    hash_src = {"property" => {"bedroom_count" => {"king_bed" => 3, "queen_bed" => 1}, "bathroom_count" => ["1", "4+"]}}
    hash_dst = {"property" => {"bedroom_count" => {"king_bed" => 2, "queen_bed" => 4}, "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => {"king_bed" => 3, "queen_bed" => 1}, "bathroom_count" => ["2","1","4+"]}}, hash_dst)

    # 3 hash layers holding arrays of int (arrays are merged)
    hash_src = {"property" => {"bedroom_count" => {"king_bed" => [3], "queen_bed" => [1]}, "bathroom_count" => ["1", "4+"]}}
    hash_dst = {"property" => {"bedroom_count" => {"king_bed" => [2], "queen_bed" => [4]}, "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => {"king_bed" => [2,3], "queen_bed" => [4,1]}, "bathroom_count" => ["2","1","4+"]}}, hash_dst)

    # 1 hash overwriting 3 hash layers holding arrays of int
    hash_src = {"property" => "1"}
    hash_dst = {"property" => {"bedroom_count" => {"king_bed" => [2], "queen_bed" => [4]}, "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => "1"}, hash_dst)

    # 1 hash NOT overwriting 3 hash layers holding arrays of int
    hash_src = {"property" => "1"}
    hash_dst = {"property" => {"bedroom_count" => {"king_bed" => [2], "queen_bed" => [4]}, "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:preserve_unmergeables => true})
    assert_equal({"property" => {"bedroom_count" => {"king_bed" => [2], "queen_bed" => [4]}, "bathroom_count" => ["2"]}}, hash_dst)

    # 3 hash layers holding arrays of int (arrays are merged) but second hash's array is overwritten
    hash_src = {"property" => {"bedroom_count" => {"king_bed" => [3], "queen_bed" => [1]}, "bathroom_count" => "1"}}
    hash_dst = {"property" => {"bedroom_count" => {"king_bed" => [2], "queen_bed" => [4]}, "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => {"king_bed" => [2,3], "queen_bed" => [4,1]}, "bathroom_count" => "1"}}, hash_dst)

    # 3 hash layers holding arrays of int (arrays are merged) but second hash's array is NOT overwritten
    hash_src = {"property" => {"bedroom_count" => {"king_bed" => [3], "queen_bed" => [1]}, "bathroom_count" => "1"}}
    hash_dst = {"property" => {"bedroom_count" => {"king_bed" => [2], "queen_bed" => [4]}, "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:preserve_unmergeables => true})
    assert_equal({"property" => {"bedroom_count" => {"king_bed" => [2,3], "queen_bed" => [4,1]}, "bathroom_count" => ["2"]}}, hash_dst)

    # 3 hash layers holding arrays of int, but one holds int. This one overwrites, but the rest merge
    hash_src = {"property" => {"bedroom_count" => {"king_bed" => 3, "queen_bed" => [1]}, "bathroom_count" => ["1"]}}
    hash_dst = {"property" => {"bedroom_count" => {"king_bed" => [2], "queen_bed" => [4]}, "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => {"king_bed" => 3, "queen_bed" => [4,1]}, "bathroom_count" => ["2","1"]}}, hash_dst)

    # 3 hash layers holding arrays of int, but source is incomplete.
    hash_src = {"property" => {"bedroom_count" => {"king_bed" => [3]}, "bathroom_count" => ["1"]}}
    hash_dst = {"property" => {"bedroom_count" => {"king_bed" => [2], "queen_bed" => [4]}, "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => {"king_bed" => [2,3], "queen_bed" => [4]}, "bathroom_count" => ["2","1"]}}, hash_dst)

    # 3 hash layers holding arrays of int, but source is shorter and has new 2nd level ints.
    hash_src = {"property" => {"bedroom_count" => {2=>3, "king_bed" => [3]}, "bathroom_count" => ["1"]}}
    hash_dst = {"property" => {"bedroom_count" => {"king_bed" => [2], "queen_bed" => [4]}, "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => {2=>3, "king_bed" => [2,3], "queen_bed" => [4]}, "bathroom_count" => ["2","1"]}}, hash_dst)

    # 3 hash layers holding arrays of int, but source is empty
    hash_src = {}
    hash_dst = {"property" => {"bedroom_count" => {"king_bed" => [2], "queen_bed" => [4]}, "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => {"king_bed" => [2], "queen_bed" => [4]}, "bathroom_count" => ["2"]}}, hash_dst)

    # 3 hash layers holding arrays of int, but dest is empty
    hash_src = {"property" => {"bedroom_count" => {2=>3, "king_bed" => [3]}, "bathroom_count" => ["1"]}}
    hash_dst = {}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => {2=>3, "king_bed" => [3]}, "bathroom_count" => ["1"]}}, hash_dst)

    # 3 hash layers holding arrays of int, but source includes a nil in the array
    hash_src = {"property" => {"bedroom_count" => {"king_bed" => [nil], "queen_bed" => [1, nil]}, "bathroom_count" => [nil, "1"]}}
    hash_dst = {"property" => {"bedroom_count" => {"king_bed" => [2], "queen_bed" => [4]}, "bathroom_count" => ["2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => {"king_bed" => [2,nil], "queen_bed" => [4, 1, nil]}, "bathroom_count" => ["2", nil, "1"]}}, hash_dst)

    # 3 hash layers holding arrays of int, but destination includes a nil in the array
    hash_src = {"property" => {"bedroom_count" => {"king_bed" => [3], "queen_bed" => [1]}, "bathroom_count" => ["1"]}}
    hash_dst = {"property" => {"bedroom_count" => {"king_bed" => [nil], "queen_bed" => [4, nil]}, "bathroom_count" => [nil,"2"]}}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"property" => {"bedroom_count" => {"king_bed" => [nil, 3], "queen_bed" => [4, nil, 1]}, "bathroom_count" => [nil, "2", "1"]}}, hash_dst)

    # if extend_existig_arrays == true && destination.kind_of?(Array) && source element is neither array nor hash, push source to destionation
    hash_src = { "property" => "4" }
    hash_dst = { "property" => ["1", "2", "3"] }
    DeepMerge::deep_merge!(hash_src, hash_dst, :extend_existing_arrays => true)
    assert_equal({"property" => ["1", "2", "3", "4"]}, hash_dst)

    # if extend_existig_arrays == true && destination.kind_of?(Array) && source.kind_of(Hash), push source to destionation
    hash_src = { "property" => {:number => "3"} }
    hash_dst = { "property" => [{:number => "1"}, {:number => "2"}] }
    DeepMerge::deep_merge!(hash_src, hash_dst, :extend_existing_arrays => true)
    assert_equal({"property"=>[{:number=>"1"}, {:number=>"2"}, {:number=>"3"}]}, hash_dst)

    # test parameter management for knockout_prefix and overwrite unmergable
    assert_raise(DeepMerge::InvalidParameter) {DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => ""})}
    assert_raise(DeepMerge::InvalidParameter) {DeepMerge::deep_merge!(hash_src, hash_dst, {:preserve_unmergeables => true, :knockout_prefix => ""})}
    assert_raise(DeepMerge::InvalidParameter) {DeepMerge::deep_merge!(hash_src, hash_dst, {:preserve_unmergeables => true, :knockout_prefix => "--"})}
    assert_nothing_raised(DeepMerge::InvalidParameter) {DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => "--"})}
    assert_nothing_raised(DeepMerge::InvalidParameter) {DeepMerge::deep_merge!(hash_src, hash_dst)}
    assert_nothing_raised(DeepMerge::InvalidParameter) {DeepMerge::deep_merge!(hash_src, hash_dst, {:preserve_unmergeables => true})}

    # hash holding arrays of arrays
    hash_src = {["1", "2", "3"] => ["1", "2"]}
    hash_dst = {["4", "5"] => ["3"]}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({["1","2","3"] => ["1", "2"], ["4", "5"] => ["3"]}, hash_dst)

    # test merging of hash with blank hash, and make sure that source array split still functions
    hash_src = {'property' => {'bedroom_count' => ["1","2,3"]}}
    hash_dst = {}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({'property' => {'bedroom_count' => ["1","2","3"]}}, hash_dst)

    # test merging of hash with blank hash, and make sure that source array split does not function when turned off
    hash_src = {'property' => {'bedroom_count' => ["1","2,3"]}}
    hash_dst = {}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX})
    assert_equal({'property' => {'bedroom_count' => ["1","2,3"]}}, hash_dst)

    # test merging into a blank hash with overwrite_unmergeables turned on
    hash_src = {"action"=>"browse", "controller"=>"results"}
    hash_dst = {}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:overwrite_unmergeables => true, :knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal hash_src, hash_dst

    # KNOCKOUT_PREFIX testing
    # the next few tests are looking for correct behavior from specific real-world params/session merges
    # using the custom modifiers built for param/session merges

    [nil, ","].each do |ko_split|
      # typical params/session style hash with knockout_merge elements
      hash_params = {"property"=>{"bedroom_count"=>[FIELD_KNOCKOUT_PREFIX+"1", "2", "3"]}}
      hash_session = {"property"=>{"bedroom_count"=>["1", "2", "3"]}}
      DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ko_split})
      assert_equal({"property"=>{"bedroom_count"=>["2", "3"]}}, hash_session)

      # typical params/session style hash with knockout_merge elements
      hash_params = {"property"=>{"bedroom_count"=>[FIELD_KNOCKOUT_PREFIX+"1", "2", "3"]}}
      hash_session = {"property"=>{"bedroom_count"=>["3"]}}
      DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ko_split})
      assert_equal({"property"=>{"bedroom_count"=>["3","2"]}}, hash_session)

      # typical params/session style hash with knockout_merge elements
      hash_params = {"property"=>{"bedroom_count"=>[FIELD_KNOCKOUT_PREFIX+"1", "2", "3"]}}
      hash_session = {"property"=>{"bedroom_count"=>["4"]}}
      DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ko_split})
      assert_equal({"property"=>{"bedroom_count"=>["4","2","3"]}}, hash_session)

      # typical params/session style hash with knockout_merge elements
      hash_params = {"property"=>{"bedroom_count"=>[FIELD_KNOCKOUT_PREFIX+"1", "2", "3"]}}
      hash_session = {"property"=>{"bedroom_count"=>[FIELD_KNOCKOUT_PREFIX+"1", "4"]}}
      DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ko_split})
      assert_equal({"property"=>{"bedroom_count"=>["4","2","3"]}}, hash_session)

      # typical params/session style hash with knockout_merge elements
      hash_params = {"amenity"=>{"id"=>[FIELD_KNOCKOUT_PREFIX+"1", FIELD_KNOCKOUT_PREFIX+"2", "3", "4"]}}
      hash_session = {"amenity"=>{"id"=>["1", "2"]}}
      DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ko_split})
      assert_equal({"amenity"=>{"id"=>["3","4"]}}, hash_session)
    end

    # special params/session style hash with knockout_merge elements in form src: ["1","2"] dest:["--1,--2", "3,4"]
    hash_params = {"amenity"=>{"id"=>[FIELD_KNOCKOUT_PREFIX+"1,"+FIELD_KNOCKOUT_PREFIX+"2", "3,4"]}}
    hash_session = {"amenity"=>{"id"=>["1", "2"]}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"amenity"=>{"id"=>["3","4"]}}, hash_session)

    # same as previous but without ko_split value, this merge should fail
    hash_params = {"amenity"=>{"id"=>[FIELD_KNOCKOUT_PREFIX+"1,"+FIELD_KNOCKOUT_PREFIX+"2", "3,4"]}}
    hash_session = {"amenity"=>{"id"=>["1", "2"]}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX})
    assert_equal({"amenity"=>{"id"=>["1","2","3,4"]}}, hash_session)

    # special params/session style hash with knockout_merge elements in form src: ["1","2"] dest:["--1,--2", "3,4"]
    hash_params = {"amenity"=>{"id"=>[FIELD_KNOCKOUT_PREFIX+"1,2", "3,4", "--5", "6"]}}
    hash_session = {"amenity"=>{"id"=>["1", "2"]}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"amenity"=>{"id"=>["2","3","4","6"]}}, hash_session)

    # special params/session style hash with knockout_merge elements in form src: ["--1,--2", "3,4", "--5", "6"] dest:["1,2", "3,4"]
    hash_params = {"amenity"=>{"id"=>["#{FIELD_KNOCKOUT_PREFIX}1,#{FIELD_KNOCKOUT_PREFIX}2", "3,4", "#{FIELD_KNOCKOUT_PREFIX}5", "6"]}}
    hash_session = {"amenity"=>{"id"=>["1", "2", "3", "4"]}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"amenity"=>{"id"=>["3","4","6"]}}, hash_session)


    hash_src = {"url_regions"=>[], "region"=>{"ids"=>["227,233"]}, "action"=>"browse", "task"=>"browse", "controller"=>"results"}
    hash_dst = {"region"=>{"ids"=>["227"]}}
    DeepMerge::deep_merge!(hash_src.dup, hash_dst, {:overwrite_unmergeables => true, :knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"url_regions"=>[], "region"=>{"ids"=>["227","233"]}, "action"=>"browse", "task"=>"browse", "controller"=>"results"}, hash_dst)

    hash_src = {"region"=>{"ids"=>["--","227"], "id"=>"230"}}
    hash_dst = {"region"=>{"ids"=>["227", "233", "324", "230", "230"], "id"=>"230"}}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:overwrite_unmergeables => true, :knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"region"=>{"ids"=>["227"], "id"=>"230"}}, hash_dst)

    hash_src = {"region"=>{"ids"=>["--","227", "232", "233"], "id"=>"232"}}
    hash_dst = {"region"=>{"ids"=>["227", "233", "324", "230", "230"], "id"=>"230"}}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:overwrite_unmergeables => true, :knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"region"=>{"ids"=>["227", "232", "233"], "id"=>"232"}}, hash_dst)

    hash_src = {"region"=>{"ids"=>["--,227,232,233"], "id"=>"232"}}
    hash_dst = {"region"=>{"ids"=>["227", "233", "324", "230", "230"], "id"=>"230"}}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:overwrite_unmergeables => true, :knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"region"=>{"ids"=>["227", "232", "233"], "id"=>"232"}}, hash_dst)

    hash_src = {"region"=>{"ids"=>["--,227,232","233"], "id"=>"232"}}
    hash_dst = {"region"=>{"ids"=>["227", "233", "324", "230", "230"], "id"=>"230"}}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:overwrite_unmergeables => true, :knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"region"=>{"ids"=>["227", "232", "233"], "id"=>"232"}}, hash_dst)

    hash_src = {"region"=>{"ids"=>["--,227"], "id"=>"230"}}
    hash_dst = {"region"=>{"ids"=>["227", "233", "324", "230", "230"], "id"=>"230"}}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:overwrite_unmergeables => true, :knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"region"=>{"ids"=>["227"], "id"=>"230"}}, hash_dst)

    hash_src = {"region"=>{"ids"=>["--,227"], "id"=>"230"}}
    hash_dst = {"region"=>{"ids"=>["227", "233", "324", "230", "230"], "id"=>"230"}, "action"=>"browse", "task"=>"browse", "controller"=>"results", "property_order_by"=>"property_type.descr"}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:overwrite_unmergeables => true, :knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"region"=>{"ids"=>["227"], "id"=>"230"}, "action"=>"browse", "task"=>"browse",
      "controller"=>"results", "property_order_by"=>"property_type.descr"}, hash_dst)

    hash_src = {"query_uuid"=>"6386333d-389b-ab5c-8943-6f3a2aa914d7", "region"=>{"ids"=>["--,227"], "id"=>"230"}}
    hash_dst = {"query_uuid"=>"6386333d-389b-ab5c-8943-6f3a2aa914d7", "url_regions"=>[], "region"=>{"ids"=>["227", "233", "324", "230", "230"], "id"=>"230"}, "action"=>"browse", "task"=>"browse", "controller"=>"results", "property_order_by"=>"property_type.descr"}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:overwrite_unmergeables => true, :knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"query_uuid" => "6386333d-389b-ab5c-8943-6f3a2aa914d7", "url_regions"=>[],
      "region"=>{"ids"=>["227"], "id"=>"230"}, "action"=>"browse", "task"=>"browse",
      "controller"=>"results", "property_order_by"=>"property_type.descr"}, hash_dst)

    # knock out entire dest hash if "--" is passed for source
    hash_params = {'amenity' => "--"}
    hash_session = {"amenity" => "1"}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => "--", :unpack_arrays => ","})
    assert_equal({'amenity' => ""}, hash_session)

    # knock out entire dest hash if "--" is passed for source
    hash_params = {'amenity' => ["--"]}
    hash_session = {"amenity" => "1"}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => "--", :unpack_arrays => ","})
    assert_equal({'amenity' => []}, hash_session)

    # knock out entire dest hash if "--" is passed for source
    hash_params = {'amenity' => "--"}
    hash_session = {"amenity" => ["1"]}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => "--", :unpack_arrays => ","})
    assert_equal({'amenity' => ""}, hash_session)

    # knock out entire dest hash if "--" is passed for source
    hash_params = {'amenity' => ["--"]}
    hash_session = {"amenity" => ["1"]}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => "--", :unpack_arrays => ","})
    assert_equal({'amenity' => []}, hash_session)

    # knock out entire dest hash if "--" is passed for source
    hash_params = {'amenity' => ["--"]}
    hash_session = {"amenity" => "1"}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => "--", :unpack_arrays => ","})
    assert_equal({'amenity' => []}, hash_session)

    # knock out entire dest hash if "--" is passed for source
    hash_params = {'amenity' => ["--", "2"]}
    hash_session = {'amenity' => ["1", "3", "7+"]}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => "--", :unpack_arrays => ","})
    assert_equal({'amenity' => ["2"]}, hash_session)

    # knock out entire dest hash if "--" is passed for source
    hash_params = {'amenity' => ["--", "2"]}
    hash_session = {'amenity' => "5"}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => "--", :unpack_arrays => ","})
    assert_equal({'amenity' => ['2']}, hash_session)

    # knock out entire dest hash if "--" is passed for source
    hash_params = {'amenity' => "--"}
    hash_session = {"amenity"=>{"id"=>["1", "2", "3", "4"]}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => "--", :unpack_arrays => ","})
    assert_equal({'amenity' => ""}, hash_session)

    # knock out entire dest hash if "--" is passed for source
    hash_params = {'amenity' => ["--"]}
    hash_session = {"amenity"=>{"id"=>["1", "2", "3", "4"]}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => "--", :unpack_arrays => ","})
    assert_equal({'amenity' => []}, hash_session)

    # knock out dest array if "--" is passed for source
    hash_params = {"region" => {'ids' => FIELD_KNOCKOUT_PREFIX}}
    hash_session = {"region"=>{"ids"=>["1", "2", "3", "4"]}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({'region' => {'ids' => ""}}, hash_session)

    # knock out dest array but leave other elements of hash intact
    hash_params = {"region" => {'ids' => FIELD_KNOCKOUT_PREFIX}}
    hash_session = {"region"=>{"ids"=>["1", "2", "3", "4"], 'id'=>'11'}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({'region' => {'ids' => "", 'id'=>'11'}}, hash_session)

    # knock out entire tree of dest hash
    hash_params = {"region" => FIELD_KNOCKOUT_PREFIX}
    hash_session = {"region"=>{"ids"=>["1", "2", "3", "4"], 'id'=>'11'}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({'region' => ""}, hash_session)

    # knock out entire tree of dest hash - retaining array format
    hash_params = {"region" => {'ids' => [FIELD_KNOCKOUT_PREFIX]}}
    hash_session = {"region"=>{"ids"=>["1", "2", "3", "4"], 'id'=>'11'}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({'region' => {'ids' => [], 'id'=>'11'}}, hash_session)

    # knock out entire tree of dest hash & replace with new content
    hash_params = {"region" => {'ids' => ["2", FIELD_KNOCKOUT_PREFIX, "6"]}}
    hash_session = {"region"=>{"ids"=>["1", "2", "3", "4"], 'id'=>'11'}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({'region' => {'ids' => ["2", "6"], 'id'=>'11'}}, hash_session)

    # knock out entire tree of dest hash & replace with new content
    hash_params = {"region" => {'ids' => ["7", FIELD_KNOCKOUT_PREFIX, "6"]}}
    hash_session = {"region"=>{"ids"=>["1", "2", "3", "4"], 'id'=>'11'}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({'region' => {'ids' => ["7", "6"], 'id'=>'11'}}, hash_session)

    # edge test: make sure that when we turn off knockout_prefix that all values are processed correctly
    hash_params = {"region" => {'ids' => ["7", "--", "2", "6,8"]}}
    hash_session = {"region"=>{"ids"=>["1", "2", "3", "4"], 'id'=>'11'}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:unpack_arrays => ","})
    assert_equal({'region' => {'ids' => ["1", "2", "3", "4", "7", "--", "6", "8"], 'id'=>'11'}}, hash_session)

    # edge test 2: make sure that when we turn off source array split that all values are processed correctly
    hash_params = {"region" => {'ids' => ["7", "3", "--", "6,8"]}}
    hash_session = {"region"=>{"ids"=>["1", "2", "3", "4"], 'id'=>'11'}}
    DeepMerge::deep_merge!(hash_params, hash_session)
    assert_equal({'region' => {'ids' => ["1", "2", "3", "4", "7", "--", "6,8"], 'id'=>'11'}}, hash_session)

    # Example: src = {'key' => "--1"}, dst = {'key' => "1"} -> merges to {'key' => ""}
    hash_params = {"amenity"=>"--1"}
    hash_session = {"amenity"=>"1"}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX})
    assert_equal({"amenity"=>""}, hash_session)

    # Example: src = {'key' => "--1"}, dst = {'key' => "2"} -> merges to {'key' => ""}
    hash_params = {"amenity"=>"--1"}
    hash_session = {"amenity"=>"2"}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX})
    assert_equal({"amenity"=>""}, hash_session)

    # Example: src = {'key' => "--1"}, dst = {'key' => "1"} -> merges to {'key' => ""}
    hash_params = {"amenity"=>["--1"]}
    hash_session = {"amenity"=>"1"}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX})
    assert_equal({"amenity"=>[]}, hash_session)

    # Example: src = {'key' => "--1"}, dst = {'key' => "1"} -> merges to {'key' => ""}
    hash_params = {"amenity"=>["--1"]}
    hash_session = {"amenity"=>["1"]}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX})
    assert_equal({"amenity"=>[]}, hash_session)

    # Example: src = {'key' => "--1"}, dst = {'key' => "1"} -> merges to {'key' => ""}
    hash_params = {"amenity"=>"--1"}
    hash_session = {}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX})
    assert_equal({"amenity"=>""}, hash_session)


    # Example: src = {'key' => "--1"}, dst = {'key' => "1"} -> merges to {'key' => ""}
    hash_params = {"amenity"=>"--1"}
    hash_session = {"amenity"=>["1"]}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX})
    assert_equal({"amenity"=>""}, hash_session)

    #are unmerged hashes passed unmodified w/out :unpack_arrays?
    hash_params = {"amenity"=>{"id"=>["26,27"]}}
    hash_session = {}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX})
    assert_equal({"amenity"=>{"id"=>["26,27"]}}, hash_session)

    #hash should be merged
    hash_params = {"amenity"=>{"id"=>["26,27"]}}
    hash_session = {}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"amenity"=>{"id"=>["26","27"]}}, hash_session)

    # second merge of same values should result in no change in output
    hash_params = {"amenity"=>{"id"=>["26,27"]}}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"amenity"=>{"id"=>["26","27"]}}, hash_session)

    #hashes with knockout values are suppressed
    hash_params = {"amenity"=>{"id"=>["#{FIELD_KNOCKOUT_PREFIX}26,#{FIELD_KNOCKOUT_PREFIX}27,28"]}}
    hash_session = {}
    DeepMerge::deep_merge!(hash_params, hash_session, {:knockout_prefix => FIELD_KNOCKOUT_PREFIX, :unpack_arrays => ","})
    assert_equal({"amenity"=>{"id"=>["28"]}}, hash_session)

    hash_src= {'region' =>{'ids'=>['--']}, 'query_uuid' => 'zzz'}
    hash_dst= {'region' =>{'ids'=>['227','2','3','3']}, 'query_uuid' => 'zzz'}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => '--', :unpack_arrays => ","})
    assert_equal({'region' =>{'ids'=>[]}, 'query_uuid' => 'zzz'}, hash_dst)

    hash_src= {'region' =>{'ids'=>['--']}, 'query_uuid' => 'zzz'}
    hash_dst= {'region' =>{'ids'=>['227','2','3','3'], 'id' => '3'}, 'query_uuid' => 'zzz'}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => '--', :unpack_arrays => ","})
    assert_equal({'region' =>{'ids'=>[], 'id'=>'3'}, 'query_uuid' => 'zzz'}, hash_dst)

    hash_src= {'region' =>{'ids'=>['--']}, 'query_uuid' => 'zzz'}
    hash_dst= {'region' =>{'muni_city_id' => '2244', 'ids'=>['227','2','3','3'], 'id'=>'3'}, 'query_uuid' => 'zzz'}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => '--', :unpack_arrays => ","})
    assert_equal({'region' =>{'muni_city_id' => '2244', 'ids'=>[], 'id'=>'3'}, 'query_uuid' => 'zzz'}, hash_dst)

    hash_src= {'region' =>{'ids'=>['--'], 'id' => '5'}, 'query_uuid' => 'zzz'}
    hash_dst= {'region' =>{'muni_city_id' => '2244', 'ids'=>['227','2','3','3'], 'id'=>'3'}, 'query_uuid' => 'zzz'}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => '--', :unpack_arrays => ","})
    assert_equal({'region' =>{'muni_city_id' => '2244', 'ids'=>[], 'id'=>'5'}, 'query_uuid' => 'zzz'}, hash_dst)

    hash_src= {'region' =>{'ids'=>['--', '227'], 'id' => '5'}, 'query_uuid' => 'zzz'}
    hash_dst= {'region' =>{'muni_city_id' => '2244', 'ids'=>['227','2','3','3'], 'id'=>'3'}, 'query_uuid' => 'zzz'}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => '--', :unpack_arrays => ","})
    assert_equal({'region' =>{'muni_city_id' => '2244', 'ids'=>['227'], 'id'=>'5'}, 'query_uuid' => 'zzz'}, hash_dst)

    hash_src= {'region' =>{'muni_city_id' => '--', 'ids'=>'--', 'id'=>'5'}, 'query_uuid' => 'zzz'}
    hash_dst= {'region' =>{'muni_city_id' => '2244', 'ids'=>['227','2','3','3'], 'id'=>'3'}, 'query_uuid' => 'zzz'}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => '--', :unpack_arrays => ","})
    assert_equal({'region' =>{'muni_city_id' => '', 'ids'=>'', 'id'=>'5'}, 'query_uuid' => 'zzz'}, hash_dst)

    hash_src= {'region' =>{'muni_city_id' => '--', 'ids'=>['--'], 'id'=>'5'}, 'query_uuid' => 'zzz'}
    hash_dst= {'region' =>{'muni_city_id' => '2244', 'ids'=>['227','2','3','3'], 'id'=>'3'}, 'query_uuid' => 'zzz'}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => '--', :unpack_arrays => ","})
    assert_equal({'region' =>{'muni_city_id' => '', 'ids'=>[], 'id'=>'5'}, 'query_uuid' => 'zzz'}, hash_dst)

    hash_src= {'region' =>{'muni_city_id' => '--', 'ids'=>['--','227'], 'id'=>'5'}, 'query_uuid' => 'zzz'}
    hash_dst= {'region' =>{'muni_city_id' => '2244', 'ids'=>['227','2','3','3'], 'id'=>'3'}, 'query_uuid' => 'zzz'}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => '--', :unpack_arrays => ","})
    assert_equal({'region' =>{'muni_city_id' => '', 'ids'=>['227'], 'id'=>'5'}, 'query_uuid' => 'zzz'}, hash_dst)

    hash_src = {"muni_city_id"=>"--", "id"=>""}
    hash_dst = {"muni_city_id"=>"", "id"=>""}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => '--', :unpack_arrays => ","})
    assert_equal({"muni_city_id"=>"", "id"=>""}, hash_dst)

    hash_src = {"region"=>{"muni_city_id"=>"--", "id"=>""}}
    hash_dst = {"region"=>{"muni_city_id"=>"", "id"=>""}}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => '--', :unpack_arrays => ","})
    assert_equal({"region"=>{"muni_city_id"=>"", "id"=>""}}, hash_dst)

    hash_src = {"query_uuid"=>"a0dc3c84-ec7f-6756-bdb0-fff9157438ab", "url_regions"=>[], "region"=>{"muni_city_id"=>"--", "id"=>""}, "property"=>{"property_type_id"=>"", "search_rate_min"=>"", "search_rate_max"=>""}, "task"=>"search", "run_query"=>"Search"}
    hash_dst = {"query_uuid"=>"a0dc3c84-ec7f-6756-bdb0-fff9157438ab", "url_regions"=>[], "region"=>{"muni_city_id"=>"", "id"=>""}, "property"=>{"property_type_id"=>"", "search_rate_min"=>"", "search_rate_max"=>""}, "task"=>"search", "run_query"=>"Search"}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:knockout_prefix => '--', :unpack_arrays => ","})
    assert_equal({"query_uuid"=>"a0dc3c84-ec7f-6756-bdb0-fff9157438ab", "url_regions"=>[], "region"=>{"muni_city_id"=>"", "id"=>""}, "property"=>{"property_type_id"=>"", "search_rate_min"=>"", "search_rate_max"=>""}, "task"=>"search", "run_query"=>"Search"}, hash_dst)

    # hash of array of hashes
    hash_src = {"item" => [{"1" => "3"}, {"2" => "4"}]}
    hash_dst = {"item" => [{"3" => "5"}]}
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"item" => [{"3" => "5"}, {"1" => "3"}, {"2" => "4"}]}, hash_dst)

    ######################################
    # tests for "merge_hash_arrays" option

    hash_src = {"item" => [{"1" => "3"}]}
    hash_dst = {"item" => [{"3" => "5"}]}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:merge_hash_arrays => true})
    assert_equal({"item" => [{"3" => "5", "1" => "3"}]}, hash_dst)

    hash_src = {"item" => [{"1" => "3"}, {"2" => "4"}]}
    hash_dst = {"item" => [{"3" => "5"}]}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:merge_hash_arrays => true})
    assert_equal({"item" => [{"3" => "5", "1" => "3"}, {"2" => "4"}]}, hash_dst)

    hash_src = {"item" => [{"1" => "3"}]}
    hash_dst = {"item" => [{"3" => "5"}, {"2" => "4"}]}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:merge_hash_arrays => true})
    assert_equal({"item" => [{"3" => "5", "1" => "3"}, {"2" => "4"}]}, hash_dst)

    # if arrays contain non-hash objects, the :merge_hash_arrays option has
    # no effect.
    hash_src = {"item" => [{"1" => "3"}, "str"]}  # contains "str", non-hash
    hash_dst = {"item" => [{"3" => "5"}]}
    DeepMerge::deep_merge!(hash_src, hash_dst, {:merge_hash_arrays => true})
    assert_equal({"item" => [{"3" => "5"}, {"1" => "3"}, "str"]}, hash_dst)

    # Merging empty strings
    s1, s2 = "hello", ""
    [s1, s2].each { |s| s.extend StringBlank }
    hash_dst = {"item" => s1 }
    hash_src = {"item" => s2 }
    DeepMerge::deep_merge!(hash_src, hash_dst)
    assert_equal({"item" => ""}, hash_dst)
  end # test_deep_merge
end