tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

async-gen-decl-dstr-array-elem-trlg-iter-elision-iter-nrml-close-skip.js (2318B)

      1 // |reftest| async
      2 // This file was procedurally generated from the following sources:
      3 // - src/dstr-assignment-for-await/array-elem-trlg-iter-elision-iter-nrml-close-skip.case
      4 // - src/dstr-assignment-for-await/async-generator/async-gen-decl.template
      5 /*---
      6 description: IteratorClose not invoked when elision exhausts the iterator (for-await-of statement in an async generator declaration)
      7 esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
      8 features: [Symbol.iterator, destructuring-binding, async-iteration]
      9 flags: [generated, async]
     10 info: |
     11    IterationStatement :
     12      for await ( LeftHandSideExpression of AssignmentExpression ) Statement
     13 
     14    1. Let keyResult be the result of performing ? ForIn/OfHeadEvaluation(« »,
     15       AssignmentExpression, iterate).
     16    2. Return ? ForIn/OfBodyEvaluation(LeftHandSideExpression, Statement,
     17       keyResult, assignment, labelSet).
     18 
     19    13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation
     20 
     21    [...]
     22    5. If destructuring is true and if lhsKind is assignment, then
     23       a. Assert: lhs is a LeftHandSideExpression.
     24       b. Let assignmentPattern be the parse of the source text corresponding to
     25          lhs using AssignmentPattern as the goal symbol.
     26    [...]
     27 
     28    ArrayAssignmentPattern :
     29        [ AssignmentElementList , Elisionopt AssignmentRestElementopt ]
     30 
     31    [...]
     32    5. If Elision is present, then
     33       a. Let status be the result of performing
     34          IteratorDestructuringAssignmentEvaluation of Elision with
     35          iteratorRecord as the argument.
     36       b. If status is an abrupt completion, then
     37 
     38    [...]
     39 
     40    7. If iteratorRecord.[[done]] is false, return IteratorClose(iterator,
     41       status).
     42    9. Return Completion(status).
     43 
     44 ---*/
     45 let nextCount = 0;
     46 let returnCount = 0;
     47 let x;
     48 let iterator = {
     49  next() {
     50    nextCount += 1;
     51 
     52    return { done: nextCount > 1 };
     53  },
     54  return() {
     55    returnCount += 1;
     56  }
     57 };
     58 let iterable = {
     59  [Symbol.iterator]() {
     60    return iterator;
     61  }
     62 };
     63 
     64 let iterCount = 0;
     65 async function * fn() {
     66  for await ([ x , , ] of [iterable]) {
     67    assert.sameValue(nextCount, 2);
     68    assert.sameValue(returnCount, 0);
     69 
     70 
     71    iterCount += 1;
     72  }
     73 }
     74 
     75 let iter = fn();
     76 
     77 iter.next()
     78  .then(() => assert.sameValue(iterCount, 1, 'iteration occurred as expected'), $DONE)
     79  .then($DONE, $DONE);