How to use the jschardet.Constants function in jschardet

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 *--------------------------------------------------------------------------------------------*/

'use strict';

import * as jschardet from 'jschardet';

jschardet.Constants.MINIMUM_THRESHOLD = 0.2;

function detectEncodingByBOM(buffer: Buffer): string | null {
	if (!buffer || buffer.length < 2) {
		return null;
	}

	const b0 = buffer.readUInt8(0);
	const b1 = buffer.readUInt8(1);

	// UTF-16 BE
	if (b0 === 0xFE && b1 === 0xFF) {
		return 'utf16be';
	}

	// UTF-16 LE
	if (b0 === 0xFF && b1 === 0xFE) {