named-dflt-ary-ptrn-rest-id-elision.js (1679B)
1 // |reftest| async 2 // This file was procedurally generated from the following sources: 3 // - src/dstr-binding/ary-ptrn-rest-id-elision.case 4 // - src/dstr-binding/default/async-gen-func-named-expr-dflt.template 5 /*--- 6 description: Rest element following elision elements (async generator named function expression (default parameter)) 7 esid: sec-asyncgenerator-definitions-evaluation 8 features: [async-iteration] 9 flags: [generated, async] 10 info: | 11 AsyncGeneratorExpression : async [no LineTerminator here] function * BindingIdentifier 12 ( FormalParameters ) { AsyncGeneratorBody } 13 14 [...] 15 7. Let closure be ! AsyncGeneratorFunctionCreate(Normal, FormalParameters, 16 AsyncGeneratorBody, funcEnv, strict). 17 [...] 18 19 20 13.3.3.6 Runtime Semantics: IteratorBindingInitialization 21 ArrayBindingPattern : [ Elisionopt BindingRestElement ] 22 1. If Elision is present, then 23 a. Let status be the result of performing 24 IteratorDestructuringAssignmentEvaluation of Elision with 25 iteratorRecord as the argument. 26 b. ReturnIfAbrupt(status). 27 2. Return the result of performing IteratorBindingInitialization for 28 BindingRestElement with iteratorRecord and environment as arguments. 29 ---*/ 30 var values = [1, 2, 3, 4, 5]; 31 32 33 var callCount = 0; 34 var f; 35 f = async function* h([ , , ...x] = values) { 36 assert(Array.isArray(x)); 37 assert.sameValue(x.length, 3); 38 assert.sameValue(x[0], 3); 39 assert.sameValue(x[1], 4); 40 assert.sameValue(x[2], 5); 41 assert.notSameValue(x, values); 42 callCount = callCount + 1; 43 }; 44 45 f().next().then(() => { 46 assert.sameValue(callCount, 1, 'invoked exactly once'); 47 }).then($DONE, $DONE);