mirror of
				https://github.com/tc39/test262.git
				synced 2025-10-31 03:34:08 +01:00 
			
		
		
		
	
		
			
				
	
	
		
			107 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			107 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| // 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-class-definitions-runtime-semantics-evaluation
 | |
| es6id: 14.5.16
 | |
| features: [generators, default-parameters]
 | |
| info: |
 | |
|     ClassExpression : class BindingIdentifieropt ClassTail
 | |
| 
 | |
|     1. If BindingIdentifieropt is not present, let className be undefined.
 | |
|     2. Else, let className be StringValue of BindingIdentifier.
 | |
|     3. 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.
 | |
|         [...]
 | |
| 
 | |
|     14.4.13 Runtime Semantics: PropertyDefinitionEvaluation
 | |
| 
 | |
|     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.
 | |
|     [...]
 | |
| 
 | |
|     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 C = class {
 | |
|   *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().next();
 | |
| 
 | |
| assert.sameValue(callCount, 1, 'method invoked exactly once');
 |