ary-ptrn-elision.js (1704B)
1 // |reftest| async 2 // This file was procedurally generated from the following sources: 3 // - src/dstr-binding/ary-ptrn-elision.case 4 // - src/dstr-binding/default/async-gen-func-expr.template 5 /*--- 6 description: Elision advances iterator (async generator function expression) 7 esid: sec-asyncgenerator-definitions-evaluation 8 features: [generators, async-iteration] 9 flags: [generated, async] 10 info: | 11 AsyncGeneratorExpression : async [no LineTerminator here] function * ( FormalParameters ) { 12 AsyncGeneratorBody } 13 14 [...] 15 3. Let closure be ! AsyncGeneratorFunctionCreate(Normal, FormalParameters, 16 AsyncGeneratorBody, scope, strict). 17 [...] 18 19 20 13.3.3.6 Runtime Semantics: IteratorBindingInitialization 21 22 ArrayBindingPattern : [ Elision ] 23 24 1. Return the result of performing 25 IteratorDestructuringAssignmentEvaluation of Elision with iteratorRecord 26 as the argument. 27 28 12.14.5.3 Runtime Semantics: IteratorDestructuringAssignmentEvaluation 29 30 Elision : , 31 32 1. If iteratorRecord.[[done]] is false, then 33 a. Let next be IteratorStep(iteratorRecord.[[iterator]]). 34 b. If next is an abrupt completion, set iteratorRecord.[[done]] to true. 35 c. ReturnIfAbrupt(next). 36 d. If next is false, set iteratorRecord.[[done]] to true. 37 2. Return NormalCompletion(empty). 38 39 ---*/ 40 var first = 0; 41 var second = 0; 42 function* g() { 43 first += 1; 44 yield; 45 second += 1; 46 }; 47 48 49 var callCount = 0; 50 var f; 51 f = async function*([,]) { 52 assert.sameValue(first, 1); 53 assert.sameValue(second, 0); 54 callCount = callCount + 1; 55 }; 56 57 f(g()).next().then(() => { 58 assert.sameValue(callCount, 1, 'invoked exactly once'); 59 }).then($DONE, $DONE);