38 lines
1.6 KiB
JavaScript
Executable file
38 lines
1.6 KiB
JavaScript
Executable file
var global = require('../internals/global');
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var shared = require('../internals/shared-store');
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var isCallable = require('../internals/is-callable');
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var create = require('../internals/object-create');
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var getPrototypeOf = require('../internals/object-get-prototype-of');
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var redefine = require('../internals/redefine');
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var wellKnownSymbol = require('../internals/well-known-symbol');
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var IS_PURE = require('../internals/is-pure');
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var USE_FUNCTION_CONSTRUCTOR = 'USE_FUNCTION_CONSTRUCTOR';
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var ASYNC_ITERATOR = wellKnownSymbol('asyncIterator');
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var AsyncIterator = global.AsyncIterator;
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var PassedAsyncIteratorPrototype = shared.AsyncIteratorPrototype;
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var AsyncIteratorPrototype, prototype;
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if (PassedAsyncIteratorPrototype) {
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AsyncIteratorPrototype = PassedAsyncIteratorPrototype;
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} else if (isCallable(AsyncIterator)) {
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AsyncIteratorPrototype = AsyncIterator.prototype;
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} else if (shared[USE_FUNCTION_CONSTRUCTOR] || global[USE_FUNCTION_CONSTRUCTOR]) {
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try {
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// eslint-disable-next-line no-new-func -- we have no alternatives without usage of modern syntax
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prototype = getPrototypeOf(getPrototypeOf(getPrototypeOf(Function('return async function*(){}()')())));
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if (getPrototypeOf(prototype) === Object.prototype) AsyncIteratorPrototype = prototype;
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} catch (error) { /* empty */ }
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}
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if (!AsyncIteratorPrototype) AsyncIteratorPrototype = {};
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else if (IS_PURE) AsyncIteratorPrototype = create(AsyncIteratorPrototype);
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if (!isCallable(AsyncIteratorPrototype[ASYNC_ITERATOR])) {
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redefine(AsyncIteratorPrototype, ASYNC_ITERATOR, function () {
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return this;
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});
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}
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module.exports = AsyncIteratorPrototype;
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