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// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-elision.case
// - src/dstr-binding/default/gen-method-dflt.template
/*---
description: Elision advances iterator (generator method (default parameter))
esid: sec-generator-function-definitions-runtime-semantics-propertydefinitionevaluation
features: [generators, destructuring-binding, default-parameters]
flags: [generated]
info: |
GeneratorMethod :
* PropertyName ( StrictFormalParameters ) { GeneratorBody }
1. Let propKey be the result of evaluating PropertyName.
2. ReturnIfAbrupt(propKey).
3. If the function code for this GeneratorMethod 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 GeneratorFunctionCreate(Method,
StrictFormalParameters, GeneratorBody, scope, strict).
[...]
9.2.1 [[Call]] ( thisArgument, argumentsList)
[...]
7. Let result be OrdinaryCallEvaluateBody(F, argumentsList).
[...]
9.2.1.3 OrdinaryCallEvaluateBody ( F, argumentsList )
1. Let status be FunctionDeclarationInstantiation(F, argumentsList).
[...]
9.2.12 FunctionDeclarationInstantiation(func, argumentsList)
[...]
23. Let iteratorRecord be Record {[[iterator]]:
CreateListIterator(argumentsList), [[done]]: false}.
24. If hasDuplicates is true, then
[...]
25. Else,
b. Let formalStatus be IteratorBindingInitialization for formals with
iteratorRecord and env as arguments.
[...]
13.3.3.6 Runtime Semantics: IteratorBindingInitialization
ArrayBindingPattern : [ Elision ]
1. Return the result of performing
IteratorDestructuringAssignmentEvaluation of Elision with iteratorRecord
as the argument.
12.14.5.3 Runtime Semantics: IteratorDestructuringAssignmentEvaluation
Elision : ,
1. If iteratorRecord.[[done]] is false, then
a. Let next be IteratorStep(iteratorRecord.[[iterator]]).
b. If next is an abrupt completion, set iteratorRecord.[[done]] to true.
c. ReturnIfAbrupt(next).
d. If next is false, set iteratorRecord.[[done]] to true.
2. Return NormalCompletion(empty).
---*/
var first = 0;
var second = 0;
function* g() {
first += 1;
yield;
second += 1;
};
var callCount = 0;
var obj = {
*method([,] = g()) {
assert.sameValue(first, 1);
assert.sameValue(second, 0);
callCount = callCount + 1;
}
};
obj.method().next();
assert.sameValue(callCount, 1, 'generator method invoked exactly once');
reportCompare(0, 0);