fuzzymatch.js — svelte Source File

Source Code

/**
 * @param {string} name
 * @param {string[]} names
 * @returns {string | null}
 */
export default function fuzzymatch(name, names) {
	if (names.length === 0) return null;

	const set = new FuzzySet(names);
	const matches = set.get(name);

	return matches && matches[0][0] > 0.7 ? matches[0][1] : null;
}

// adapted from https://github.com/Glench/fuzzyset.js/blob/master/lib/fuzzyset.js in 2016
// BSD Licensed (see https://github.com/Glench/fuzzyset.js/issues/10)

const GRAM_SIZE_LOWER = 2;
const GRAM_SIZE_UPPER = 3;

// return an edit distance from 0 to 1

/**
 * @param {string} str1
 * @param {string} str2
 */
function _distance(str1, str2) {
	if (str1 === null && str2 === null) {
		throw 'Trying to compare two null values';
	}
	if (str1 === null || str2 === null) return 0;
	str1 = String(str1);
	str2 = String(str2);

	const distance = levenshtein(str1, str2);
	return 1 - distance / Math.max(str1.length, str2.length);
}

// helper functions

/**
 * @param {string} str1
 * @param {string} str2
 */
function levenshtein(str1, str2) {
	/** @type {number[]} */
	const current = [];
	let prev = 0;

	for (let i = 0; i <= str2.length; i++) {
		for (let j = 0; j <= str1.length; j++) {
			let value;

			if (i && j) {
				if (str1.charAt(j - 1) === str2.charAt(i - 1)) {
					value = prev;
				} else {
					value = Math.min(current[j], current[j - 1], prev) + 1;
				}
			} else {
// ... (222 more lines)