| // 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 (method) |
| esid: sec-runtime-semantics-definemethod |
| es6id: 14.3.8 |
| features: [default-parameters] |
| info: | |
| 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; |
| var obj = { |
| method(x = arguments[2], y = arguments[3], z) { |
| assert.sameValue(x, 'third', 'first parameter'); |
| assert.sameValue(y, 'fourth', 'second parameter'); |
| assert.sameValue(z, 'third', 'third parameter'); |
| callCount = callCount + 1; |
| } |
| }; |
| |
| obj.method(undefined, undefined, 'third', 'fourth'); |
| |
| assert.sameValue(callCount, 1, 'method invoked exactly once'); |