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// |reftest| async
// This file was procedurally generated from the following sources:
// - src/arguments/args-trailing-comma-undefined.case
// - src/arguments/default/cls-expr-async-gen-meth.template
/*---
description: A trailing comma after undefined should not increase the arguments.length (class expression async generator method)
esid: sec-class-definitions-runtime-semantics-evaluation
features: [async-iteration]
flags: [generated, async]
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.
[...]
Runtime Semantics: PropertyDefinitionEvaluation
AsyncGeneratorMethod :
async [no LineTerminator here] * PropertyName ( UniqueFormalParameters )
{ AsyncGeneratorBody }
1. Let propKey be the result of evaluating PropertyName.
2. ReturnIfAbrupt(propKey).
3. If the function code for this AsyncGeneratorMethod 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 ! AsyncGeneratorFunctionCreate(Method, UniqueFormalParameters,
AsyncGeneratorBody, scope, strict).
[...]
Trailing comma in the arguments list
Left-Hand-Side Expressions
Arguments :
( )
( ArgumentList )
( ArgumentList , )
ArgumentList :
AssignmentExpression
... AssignmentExpression
ArgumentList , AssignmentExpression
ArgumentList , ... AssignmentExpression
---*/
var callCount = 0;
var C = class {
async *method() {
assert.sameValue(arguments.length, 2);
assert.sameValue(arguments[0], 42);
assert.sameValue(arguments[1], undefined);
callCount = callCount + 1;
}
};
// Stores a reference `ref` for case evaluation
var ref = C.prototype.method;
ref(42, undefined,).next().then(() => {
assert.sameValue(callCount, 1, 'method invoked exactly once');
}).then($DONE, $DONE);