fei.wang
10 天以前 ae7b22322555448d95fd56f505bafa325c167a26
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'use strict';
 
var SLOT = require('internal-slot');
var $SyntaxError = require('es-errors/syntax');
 
var $StopIteration = typeof StopIteration === 'object' ? StopIteration : null;
 
/** @type {import('.')} */
module.exports = function getStopIterationIterator(origIterator) {
    if (!$StopIteration) {
        throw new $SyntaxError('this environment lacks StopIteration');
    }
 
    SLOT.set(origIterator, '[[Done]]', false);
 
    /** @template T @typedef {T extends Iterator<infer U> ? U : never} IteratorType */
    /** @typedef {IteratorType<ReturnType<typeof getStopIterationIterator>>} T */
    var siIterator = {
        next: /** @type {() => IteratorResult<T>} */ function next() {
            // eslint-disable-next-line no-extra-parens
            var iterator = /** @type {typeof origIterator} */ (SLOT.get(this, '[[Iterator]]'));
            var done = !!SLOT.get(iterator, '[[Done]]');
            try {
                return {
                    done: done,
                    // eslint-disable-next-line no-extra-parens
                    value: done ? void undefined : /** @type {T} */ (iterator.next())
                };
            } catch (e) {
                SLOT.set(iterator, '[[Done]]', true);
                if (e !== $StopIteration) {
                    throw e;
                }
                return {
                    done: true,
                    value: void undefined
                };
            }
        }
    };
 
    SLOT.set(siIterator, '[[Iterator]]', origIterator);
 
    // @ts-expect-error TODO FIXME
    return siIterator;
};