summaryrefslogtreecommitdiffstats
path: root/js/src/tests/test262/language/statements/for-of/dstr/array-elem-init-yield-expr.js
blob: 986b32c2a1e1449ed98b93e3553bfd04bb37cc28 (plain)
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
// This file was procedurally generated from the following sources:
// - src/dstr-assignment/array-elem-init-yield-expr.case
// - src/dstr-assignment/default/for-of.template
/*---
description: When a `yield` token appears within the Initializer of an AssignmentElement within a generator function body, it behaves as a YieldExpression. (For..of statement)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
features: [generators, destructuring-binding]
flags: [generated]
info: |
    IterationStatement :
      for ( LeftHandSideExpression of AssignmentExpression ) Statement

    1. Let keyResult be the result of performing ? ForIn/OfHeadEvaluation(« »,
       AssignmentExpression, iterate).
    2. Return ? ForIn/OfBodyEvaluation(LeftHandSideExpression, Statement,
       keyResult, assignment, labelSet).

    13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation

    [...]
    4. If destructuring is true and if lhsKind is assignment, then
       a. Assert: lhs is a LeftHandSideExpression.
       b. Let assignmentPattern be the parse of the source text corresponding to
          lhs using AssignmentPattern as the goal symbol.
    [...]
---*/
var value = [];
var iterationResult, iter, x;
iter = (function*() {

var counter = 0;

for ([ x = yield ] of [[]]) {
  
  counter += 1;
}

assert.sameValue(counter, 1);

})();

iterationResult = iter.next();

assert.sameValue(iterationResult.value, undefined);
assert.sameValue(iterationResult.done, false);
assert.sameValue(x, undefined);

iterationResult = iter.next(86);

assert.sameValue(iterationResult.value, undefined);
assert.sameValue(iterationResult.done, true);
assert.sameValue(x, 86);

reportCompare(0, 0);