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// |reftest| async
// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-elem-id-init-skipped.case
// - src/dstr-binding/default/cls-decl-async-gen-meth-dflt.template
/*---
description: Destructuring initializer is not evaluated when value is not `undefined` (class expression async generator method (default parameters))
esid: sec-class-definitions-runtime-semantics-evaluation
features: [async-iteration]
flags: [generated, async]
info: |
ClassDeclaration : class BindingIdentifier ClassTail
1. Let className be StringValue of BindingIdentifier.
2. Let value be the result of ClassDefinitionEvaluation of ClassTail with
argument className.
[...]
14.5.14 Runtime Semantics: ClassDefinitionEvaluation
21. For each ClassElement m in order from methods
a. If IsStatic of m is false, then
i. Let status be the result of performing
PropertyDefinitionEvaluation for m with arguments proto and
false.
[...]
Runtime Semantics: PropertyDefinitionEvaluation
AsyncGeneratorMethod :
async [no LineTerminator here] * PropertyName ( UniqueFormalParameters )
{ AsyncGeneratorBody }
1. Let propKey be the result of evaluating PropertyName.
2. ReturnIfAbrupt(propKey).
3. If the function code for this AsyncGeneratorMethod is strict mode code, let strict be true.
Otherwise let strict be false.
4. Let scope be the running execution context's LexicalEnvironment.
5. Let closure be ! AsyncGeneratorFunctionCreate(Method, UniqueFormalParameters,
AsyncGeneratorBody, scope, strict).
[...]
13.3.3.6 Runtime Semantics: IteratorBindingInitialization
SingleNameBinding : BindingIdentifier Initializeropt
[...]
6. If Initializer is present and v is undefined, then
[...]
7. If environment is undefined, return PutValue(lhs, v).
8. Return InitializeReferencedBinding(lhs, v).
---*/
var initCount = 0;
function counter() {
initCount += 1;
}
var callCount = 0;
class C {
async *method([w = counter(), x = counter(), y = counter(), z = counter()] = [null, 0, false, '']) {
assert.sameValue(w, null);
assert.sameValue(x, 0);
assert.sameValue(y, false);
assert.sameValue(z, '');
assert.sameValue(initCount, 0);
callCount = callCount + 1;
}
};
new C().method().next().then(() => {
assert.sameValue(callCount, 1, 'invoked exactly once');
}).then($DONE, $DONE);