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// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-init-iter-close.case
// - src/dstr-binding/default/gen-func-decl-dflt.template
/*---
description: Iterator is closed when not exhausted by pattern evaluation (generator function declaration (default parameter))
esid: sec-generator-function-definitions-runtime-semantics-instantiatefunctionobject
features: [Symbol.iterator, generators, destructuring-binding, default-parameters]
flags: [generated]
info: |
GeneratorDeclaration : function * ( FormalParameters ) { GeneratorBody }
[...]
2. Let F be GeneratorFunctionCreate(Normal, FormalParameters,
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.
[...]
13.3.3.5 Runtime Semantics: BindingInitialization
BindingPattern : ArrayBindingPattern
[...]
4. If iteratorRecord.[[done]] is false, return ? IteratorClose(iterator,
result).
[...]
---*/
var doneCallCount = 0;
var iter = {};
iter[Symbol.iterator] = function() {
return {
next: function() {
return { value: null, done: false };
},
return: function() {
doneCallCount += 1;
return {};
}
};
};
var callCount = 0;
function* f([x] = iter) {
assert.sameValue(doneCallCount, 1);
callCount = callCount + 1;
};
f().next();
assert.sameValue(callCount, 1, 'generator function invoked exactly once');
reportCompare(0, 0);
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