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// This file was procedurally generated from the following sources:
// - src/dstr-binding/obj-ptrn-prop-id-init-skipped.case
// - src/dstr-binding/default/gen-func-decl-dflt.template
/*---
description: Destructuring initializer is not evaluated when value is not `undefined` (generator function declaration (default parameter))
esid: sec-generator-function-definitions-runtime-semantics-instantiatefunctionobject
features: [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.
[...]
13.3.3.7 Runtime Semantics: KeyedBindingInitialization
BindingElement : BindingPattern Initializeropt
[...]
3. If Initializer is present and v is undefined, then
[...]
---*/
var initCount = 0;
function counter() {
initCount += 1;
}
var callCount = 0;
function* f({ s: t = counter(), u: v = counter(), w: x = counter(), y: z = counter() } = { s: null, u: 0, w: false, y: '' }) {
assert.sameValue(t, null);
assert.sameValue(v, 0);
assert.sameValue(x, false);
assert.sameValue(z, '');
assert.sameValue(initCount, 0);
assert.throws(ReferenceError, function() {
s;
});
assert.throws(ReferenceError, function() {
u;
});
assert.throws(ReferenceError, function() {
w;
});
assert.throws(ReferenceError, function() {
y;
});
callCount = callCount + 1;
};
f().next();
assert.sameValue(callCount, 1, 'generator function invoked exactly once');
reportCompare(0, 0);