// |reftest| async // This file was procedurally generated from the following sources: // - src/dstr-binding/ary-ptrn-elem-id-init-undef.case // - src/dstr-binding/default/async-gen-func-decl.template /*--- description: Destructuring initializer with an undefined value (async generator function declaration) esid: sec-asyncgenerator-definitions-instantiatefunctionobject features: [async-iteration] flags: [generated, async] info: | AsyncGeneratorDeclaration : async [no LineTerminator here] function * BindingIdentifier ( FormalParameters ) { AsyncGeneratorBody } [...] 3. Let F be ! AsyncGeneratorFunctionCreate(Normal, FormalParameters, AsyncGeneratorBody, scope, strict). [...] 13.3.3.6 Runtime Semantics: IteratorBindingInitialization SingleNameBinding : BindingIdentifier Initializeropt [...] 6. If Initializer is present and v is undefined, then a. Let defaultValue be the result of evaluating Initializer. b. Let v be GetValue(defaultValue). [...] 7. If environment is undefined, return PutValue(lhs, v). 8. Return InitializeReferencedBinding(lhs, v). ---*/ var callCount = 0; async function* f([x = 23]) { assert.sameValue(x, 23); callCount = callCount + 1; }; f([undefined]).next().then(() => { assert.sameValue(callCount, 1, 'invoked exactly once'); }).then($DONE, $DONE);