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
|
// Copyright (C) 2015 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-array.prototype.find
es6id: 22.1.3.8
description: >
Return undefined if predicate always returns a boolean false value.
info: |
22.1.3.8 Array.prototype.find ( predicate[ , thisArg ] )
...
8. Repeat, while k < len
...
d. Let testResult be ToBoolean(Call(predicate, T, «kValue, k, O»)).
...
9. Return undefined.
features: [Symbol]
---*/
var arr = ['Shoes', 'Car', 'Bike'];
var called = 0;
var result = arr.find(function(val) {
called++;
return false;
});
assert.sameValue(called, 3, 'predicate was called three times');
assert.sameValue(result, undefined);
result = arr.find(function(val) {
return '';
});
assert.sameValue(result, undefined, 'coerced string');
result = arr.find(function(val) {
return undefined;
});
assert.sameValue(result, undefined, 'coerced undefined');
result = arr.find(function(val) {
return null;
});
assert.sameValue(result, undefined, 'coerced null');
result = arr.find(function(val) {
return 0;
});
assert.sameValue(result, undefined, 'coerced 0');
result = arr.find(function(val) {
return NaN;
});
assert.sameValue(result, undefined, 'coerced NaN');
|
