| // Copyright (C) 2019 Alexey Shvayka. All rights reserved. |
| // This code is governed by the BSD license found in the LICENSE file. |
| /*--- |
| esid: sec-asyncgenerator-definitions-evaluatebody |
| description: > |
| Default [[Prototype]] value derived from realm of the async generator function. |
| info: | |
| Runtime Semantics: EvaluateBody |
| |
| ... |
| 2. Let generator be ? OrdinaryCreateFromConstructor(functionObject, "%AsyncGeneratorPrototype%", « ... »). |
| 3. Perform ! AsyncGeneratorStart(generator, FunctionBody). |
| 4. Return Completion { [[Type]]: return, [[Value]]: generator, [[Target]]: empty }. |
| |
| OrdinaryCreateFromConstructor ( constructor, intrinsicDefaultProto [ , internalSlotsList ] ) |
| |
| ... |
| 2. Let proto be ? GetPrototypeFromConstructor(constructor, intrinsicDefaultProto). |
| 3. Return ObjectCreate(proto, internalSlotsList). |
| |
| GetPrototypeFromConstructor ( constructor, intrinsicDefaultProto ) |
| |
| ... |
| 3. Let proto be ? Get(constructor, 'prototype'). |
| 4. If Type(proto) is not Object, then |
| a. Let realm be ? GetFunctionRealm(constructor). |
| b. Set proto to realm's intrinsic object named intrinsicDefaultProto. |
| 5. Return proto. |
| features: [async-iteration, Symbol] |
| ---*/ |
| |
| var fn = async function* () {}; |
| var AsyncGeneratorPrototype = Object.getPrototypeOf(fn.prototype); |
| |
| fn.prototype = undefined; |
| assert.sameValue(Object.getPrototypeOf(fn()), AsyncGeneratorPrototype, 'fn.prototype is undefined'); |
| |
| fn.prototype = null; |
| assert.sameValue(Object.getPrototypeOf(fn()), AsyncGeneratorPrototype, 'fn.prototype is null'); |
| |
| fn.prototype = false; |
| assert.sameValue(Object.getPrototypeOf(fn()), AsyncGeneratorPrototype, 'fn.prototype is a Boolean'); |
| |
| fn.prototype = ''; |
| assert.sameValue(Object.getPrototypeOf(fn()), AsyncGeneratorPrototype, 'fn.prototype is a String'); |
| |
| fn.prototype = Symbol(); |
| assert.sameValue(Object.getPrototypeOf(fn()), AsyncGeneratorPrototype, 'fn.prototype is a Symbol'); |
| |
| fn.prototype = 1; |
| assert.sameValue(Object.getPrototypeOf(fn()), AsyncGeneratorPrototype, 'fn.prototype is a Number'); |