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
|
require_relative '../spec_helper'
describe "The 'case'-construct" do
it "evaluates the body of the when clause matching the case target expression" do
case 1
when 2; false
when 1; true
end.should == true
end
it "evaluates the body of the when clause whose array expression includes the case target expression" do
case 2
when 3, 4; false
when 1, 2; true
end.should == true
end
it "evaluates the body of the when clause in left-to-right order if it's an array expression" do
@calls = []
def foo; @calls << :foo; end
def bar; @calls << :bar; end
case true
when foo, bar;
end
@calls.should == [:foo, :bar]
end
it "evaluates the body of the when clause whose range expression includes the case target expression" do
case 5
when 21..30; false
when 1..20; true
end.should == true
end
it "returns nil when no 'then'-bodies are given" do
case "a"
when "a"
when "b"
end.should == nil
end
it "evaluates the 'else'-body when no other expression matches" do
case "c"
when "a"; 'foo'
when "b"; 'bar'
else 'zzz'
end.should == 'zzz'
end
it "returns nil when no expression matches and 'else'-body is empty" do
case "c"
when "a"; "a"
when "b"; "b"
else
end.should == nil
end
it "returns 2 when a then body is empty" do
case Object.new
when Numeric then
1
when String then
# ok
else
2
end.should == 2
end
it "returns the statement following 'then'" do
case "a"
when "a" then 'foo'
when "b" then 'bar'
end.should == 'foo'
end
it "tests classes with case equality" do
case "a"
when String
'foo'
when Symbol
'bar'
end.should == 'foo'
end
it "tests with matching regexps" do
case "hello"
when /abc/; false
when /^hell/; true
end.should == true
end
it "tests with matching regexps and sets $~ and captures" do
case "foo42"
when /oo(\d+)/
$~.should be_kind_of(MatchData)
$1.should == "42"
else
flunk
end
$~.should be_kind_of(MatchData)
$1.should == "42"
end
it "tests with a string interpolated in a regexp" do
digits = '\d+'
case "foo44"
when /oo(#{digits})/
$~.should be_kind_of(MatchData)
$1.should == "44"
else
flunk
end
$~.should be_kind_of(MatchData)
$1.should == "44"
end
it "tests with a regexp interpolated within another regexp" do
digits_regexp = /\d+/
case "foo43"
when /oo(#{digits_regexp})/
$~.should be_kind_of(MatchData)
$1.should == "43"
else
flunk
end
$~.should be_kind_of(MatchData)
$1.should == "43"
end
it "does not test with equality when given classes" do
case :symbol.class
when Symbol
"bar"
when String
"bar"
else
"foo"
end.should == "foo"
end
it "takes lists of values" do
case 'z'
when 'a', 'b', 'c', 'd'
"foo"
when 'x', 'y', 'z'
"bar"
end.should == "bar"
case 'b'
when 'a', 'b', 'c', 'd'
"foo"
when 'x', 'y', 'z'
"bar"
end.should == "foo"
end
it "tests an empty array" do
case []
when []
'foo'
else
'bar'
end.should == 'foo'
end
it "expands arrays to lists of values" do
case 'z'
when *['a', 'b', 'c', 'd']
"foo"
when *['x', 'y', 'z']
"bar"
end.should == "bar"
end
it "takes an expanded array in addition to a list of values" do
case 'f'
when 'f', *['a', 'b', 'c', 'd']
"foo"
when *['x', 'y', 'z']
"bar"
end.should == "foo"
case 'b'
when 'f', *['a', 'b', 'c', 'd']
"foo"
when *['x', 'y', 'z']
"bar"
end.should == "foo"
end
it "takes an expanded array before additional listed values" do
case 'f'
when *['a', 'b', 'c', 'd'], 'f'
"foo"
when *['x', 'y', 'z']
"bar"
end.should == 'foo'
end
it "expands arrays from variables before additional listed values" do
a = ['a', 'b', 'c']
case 'a'
when *a, 'd', 'e'
"foo"
when 'x'
"bar"
end.should == "foo"
end
it "expands arrays from variables before a single additional listed value" do
a = ['a', 'b', 'c']
case 'a'
when *a, 'd'
"foo"
when 'x'
"bar"
end.should == "foo"
end
it "expands multiple arrays from variables before additional listed values" do
a = ['a', 'b', 'c']
b = ['d', 'e', 'f']
case 'f'
when *a, *b, 'g', 'h'
"foo"
when 'x'
"bar"
end.should == "foo"
end
# MR: critical
it "concats arrays before expanding them" do
a = ['a', 'b', 'c', 'd']
b = ['f']
case 'f'
when 'f', *a|b
"foo"
when *['x', 'y', 'z']
"bar"
end.should == "foo"
end
it "never matches when clauses with no values" do
case nil
when *[]
"foo"
end.should == nil
end
it "lets you define a method after the case statement" do
case (def foo; 'foo'; end; 'f')
when 'a'
'foo'
when 'f'
'bar'
end.should == 'bar'
end
it "raises a SyntaxError when 'else' is used when no 'when' is given" do
-> {
eval <<-CODE
case 4
else
true
end
CODE
}.should raise_error(SyntaxError)
end
it "raises a SyntaxError when 'else' is used before a 'when' was given" do
-> {
eval <<-CODE
case 4
else
true
when 4; false
end
CODE
}.should raise_error(SyntaxError)
end
it "supports nested case statements" do
result = false
case :x
when Symbol
case :y
when Symbol
result = true
end
end
result.should == true
end
it "supports nested case statements followed by a when with a splatted array" do
result = false
case :x
when Symbol
case :y
when Symbol
result = true
end
when *[Symbol]
result = false
end
result.should == true
end
it "supports nested case statements followed by a when with a splatted non-array" do
result = false
case :x
when Symbol
case :y
when Symbol
result = true
end
when *Symbol
result = false
end
result.should == true
end
it "works even if there's only one when statement" do
case 1
when 1
100
end.should == 100
end
it "evaluates true as only 'true' when true is the first clause" do
case 1
when true; "bad"
when Integer; "good"
end.should == "good"
end
it "evaluates false as only 'false' when false is the first clause" do
case nil
when false; "bad"
when nil; "good"
end.should == "good"
end
it "treats a literal array as its own when argument, rather than a list of arguments" do
case 'foo'
when ['foo', 'foo']; 'bad'
when 'foo'; 'good'
end.should == 'good'
end
it "takes multiple expanded arrays" do
a1 = ['f', 'o', 'o']
a2 = ['b', 'a', 'r']
case 'f'
when *a1, *['x', 'y', 'z']
"foo"
when *a2, *['x', 'y', 'z']
"bar"
end.should == "foo"
case 'b'
when *a1, *['x', 'y', 'z']
"foo"
when *a2, *['x', 'y', 'z']
"bar"
end.should == "bar"
end
it "calls === even when private" do
klass = Class.new do
def ===(o)
true
end
private :===
end
case 1
when klass.new
:called
end.should == :called
end
it "accepts complex expressions within ()" do
case 'a'
when (raise if 2+2 == 3; /a/)
:called
end.should == :called
end
it "only matches last value in complex expressions within ()" do
case 'a'
when ('a'; 'b')
:wrong_called
when ('b'; 'a')
:called
end.should == :called
end
end
describe "The 'case'-construct with no target expression" do
it "evaluates the body of the first clause when at least one of its condition expressions is true" do
case
when true, false; 'foo'
end.should == 'foo'
end
it "evaluates the body of the first when clause that is not false/nil" do
case
when false; 'foo'
when 2; 'bar'
when 1 == 1; 'baz'
end.should == 'bar'
case
when false; 'foo'
when nil; 'foo'
when 1 == 1; 'bar'
end.should == 'bar'
end
it "evaluates the body of the else clause if all when clauses are false/nil" do
case
when false; 'foo'
when nil; 'foo'
when 1 == 2; 'bar'
else 'baz'
end.should == 'baz'
end
it "evaluates multiple conditional expressions as a boolean disjunction" do
case
when true, false; 'foo'
else 'bar'
end.should == 'foo'
case
when false, true; 'foo'
else 'bar'
end.should == 'foo'
end
# Homogeneous cases are often optimized to avoid === using a jump table, and should be tested separately.
# See https://github.com/jruby/jruby/issues/6440
it "handles homogeneous cases" do
case
when 1; 'foo'
when 2; 'bar'
end.should == 'foo'
end
it "expands arrays to lists of values" do
case
when *[false]
"foo"
when *[true]
"bar"
end.should == "bar"
end
end
|
