JSTests/test262/test/language/statements/for-of/dstr/array-elem-trlg-iter-elision-iter-abpt.js

// This file was procedurally generated from the following sources:
// - src/dstr-assignment/array-elem-trlg-iter-elision-iter-abpt.case
// - src/dstr-assignment/error/for-of.template
/*---
description: Abrupt completion returned during evaluation of elision (For..of statement)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
es6id: 13.7.5.11
features: [Symbol.iterator, 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.
    [...]

    ArrayAssignmentPattern :
        [ AssignmentElementList , Elisionopt AssignmentRestElementopt ]

    [...]
    6. If Elision is present, then
       a. Let status be the result of performing
          IteratorDestructuringAssignmentEvaluation of Elision with
          iteratorRecord as the argument.
       b. If status is an abrupt completion, then
          i. If iteratorRecord.[[done]] is false, return
             IteratorClose(iterator, status).
          ii. Return Completion(status).

---*/
var nextCount = 0;
var returnCount = 0;
var iterable = {};
var x;
var iterator = {
  next: function() {
    nextCount += 1;

    if (nextCount === 2) {
      throw new Test262Error();
    }

    // Set an upper-bound to limit unnecessary iteration in non-conformant
    // implementations
    return { done: nextCount > 10 };
  },
  return: function() {
    returnCount += 1;
  }
};
iterable[Symbol.iterator] = function() {
  return iterator;
};


var counter = 0;

assert.throws(Test262Error, function() {
  for ([ x , , ] of [iterable]) {
    counter += 1;
  }
  counter += 1;
});

assert.sameValue(counter, 0);

assert.sameValue(nextCount, 2);
assert.sameValue(returnCount, 0);