tor-browser

The Tor Browser
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array-rest-iter-thrw-close-err.js (2535B)

      1 // This file was procedurally generated from the following sources:
      2 // - src/dstr-assignment/array-rest-iter-thrw-close-err.case
      3 // - src/dstr-assignment/error/for-of.template
      4 /*---
      5 description: IteratorClose is called when reference evaluation produces a "throw" completion (For..of statement)
      6 esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
      7 features: [Symbol.iterator, destructuring-binding]
      8 flags: [generated]
      9 info: |
     10    IterationStatement :
     11      for ( LeftHandSideExpression of AssignmentExpression ) Statement
     12 
     13    1. Let keyResult be the result of performing ? ForIn/OfHeadEvaluation(« »,
     14       AssignmentExpression, iterate).
     15    2. Return ? ForIn/OfBodyEvaluation(LeftHandSideExpression, Statement,
     16       keyResult, assignment, labelSet).
     17 
     18    13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation
     19 
     20    [...]
     21    4. If destructuring is true and if lhsKind is assignment, then
     22       a. Assert: lhs is a LeftHandSideExpression.
     23       b. Let assignmentPattern be the parse of the source text corresponding to
     24          lhs using AssignmentPattern as the goal symbol.
     25    [...]
     26 
     27    ArrayAssignmentPattern : [ Elisionopt AssignmentRestElement ]
     28 
     29    [...]
     30    5. Let result be the result of performing
     31       IteratorDestructuringAssignmentEvaluation of AssignmentRestElement with
     32       iteratorRecord as the argument
     33    6. If iteratorRecord.[[done]] is false, return IteratorClose(iterator,
     34       result).
     35 
     36    AssignmentRestElement[Yield] : ... DestructuringAssignmentTarget
     37 
     38    1. If DestructuringAssignmentTarget is neither an ObjectLiteral nor an
     39       ArrayLiteral, then
     40       a. Let lref be the result of evaluating DestructuringAssignmentTarget.
     41       b. ReturnIfAbrupt(lref).
     42 
     43 ---*/
     44 var nextCount = 0;
     45 var returnCount = 0;
     46 var x;
     47 function ReturnError() {}
     48 var iterable = {};
     49 var iterator = {
     50  next: function() {
     51    nextCount += 1;
     52    // Set an upper-bound to limit unnecessary iteration in non-conformant
     53    // implementations
     54    return { done: nextCount > 10 };
     55  },
     56  return: function() {
     57    returnCount += 1;
     58 
     59    // This value should be discarded.
     60    throw new ReturnError();
     61  }
     62 };
     63 var thrower = function() {
     64  throw new Test262Error();
     65 };
     66 iterable[Symbol.iterator] = function() {
     67  return iterator;
     68 };
     69 
     70 
     71 var counter = 0;
     72 
     73 assert.throws(Test262Error, function() {
     74  for ([...{}[thrower()]] of [iterable]) {
     75    counter += 1;
     76  }
     77  counter += 1;
     78 });
     79 
     80 assert.sameValue(counter, 0);
     81 
     82 assert.sameValue(nextCount, 0);
     83 assert.sameValue(returnCount, 1);
     84 
     85 reportCompare(0, 0);