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// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
description: Referencing the arguments object from a default parameter (class expression method)
esid: sec-runtime-semantics-bindingclassdeclarationevaluation
es6id: 14.5.15
features: [default-parameters]
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.
[...]
14.3.8 Runtime Semantics: DefineMethod
MethodDefinition : PropertyName ( StrictFormalParameters ) { FunctionBody }
[...]
6. Let closure be FunctionCreate(kind, StrictFormalParameters, FunctionBody,
scope, strict). If functionPrototype was passed as a parameter then pass its
value as the functionPrototype optional argument of FunctionCreate.
[...]
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.
[...]
14.1.19 Runtime Semantics: IteratorBindingInitialization
FormalsList : FormalsList , FormalParameter
1. Let status be the result of performing IteratorBindingInitialization for
FormalsList using iteratorRecord and environment as the arguments.
2. ReturnIfAbrupt(status).
3. Return the result of performing IteratorBindingInitialization for
FormalParameter using iteratorRecord and environment as the arguments.
---*/
var callCount = 0;
class C {
method(x, _ = 0) {
assert.sameValue(x, undefined, 'parameter binding value (initial)');
assert.sameValue(
arguments[0], undefined, 'arguments property value (initial)'
);
arguments[0] = 1;
assert.sameValue(
x, undefined, 'parameter binding value (after arguments modification)'
);
assert.sameValue(
arguments[0], 1, 'arguments property value (after arguments modification)'
);
x = 2;
assert.sameValue(
x, 2, 'parameter binding value (after parameter binding modification)'
);
assert.sameValue(
arguments[0],
1,
'arguments property value (after parameter binding modification)'
);
callCount = callCount + 1;
}
}
C.prototype.method();
assert.sameValue(callCount, 1, 'method invoked exactly once');
reportCompare(0, 0);