forked from M3-Academy/challenge-algorithms-v2.0
53 lines
894 B
JavaScript
53 lines
894 B
JavaScript
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'use strict';
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const {PassThrough: PassThroughStream} = require('stream');
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module.exports = options => {
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options = {...options};
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const {array} = options;
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let {encoding} = options;
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const isBuffer = encoding === 'buffer';
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let objectMode = false;
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if (array) {
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objectMode = !(encoding || isBuffer);
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} else {
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encoding = encoding || 'utf8';
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}
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if (isBuffer) {
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encoding = null;
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}
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const stream = new PassThroughStream({objectMode});
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if (encoding) {
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stream.setEncoding(encoding);
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}
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let length = 0;
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const chunks = [];
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stream.on('data', chunk => {
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chunks.push(chunk);
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if (objectMode) {
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length = chunks.length;
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} else {
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length += chunk.length;
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}
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});
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stream.getBufferedValue = () => {
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if (array) {
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return chunks;
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}
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return isBuffer ? Buffer.concat(chunks, length) : chunks.join('');
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};
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stream.getBufferedLength = () => length;
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return stream;
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};
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