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// 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');
reportCompare(0, 0);