@technobuddha/library/compareStrings/compareStrings.mjs

A large library of useful functions

import isNil from 'lodash/isNil';
import compareNumbers from '../compareNumbers';
/**
 * Compare two strings
 *
 * @param a First string
 * @param b Second string
 * @param caseInsensitive True if strings are to be compared case insensitive (default false)
 * @returns 0 if a == b; -1 if a < b; 1 if a > b
 *
 * @default caseInsensitive false
 * @default natural false
 * @default version false
 */
export function compareStrings(text1, text2, { caseInsensitive = false, natural = false, version = false } = {}) {
    if (text1 === text2)
        return 0;
    if (isNil(text1))
        return -1;
    if (isNil(text2))
        return 1;
    if (caseInsensitive) {
        text1 = text1.toLowerCase();
        text2 = text2.toLowerCase();
        if (text1 === text2)
            return 0;
    }
    if (version) {
        const v1 = text1.trim().split(/[.-]/u);
        const v2 = text2.trim().split(/[.-]/u);
        const count = Math.max(v1.length, v2.length);
        let order = 0;
        for (let i = 0; order === 0 && i < count; ++i)
            order = compareStrings(v1[i], v2[i], { natural: true });
        return order || compareNumbers(v1.length, v2.length);
    }
    else if (natural) {
        const t1 = text1.match(/(\.\d+|\d+|\D+)/ug) ?? [];
        const t2 = text2.match(/(\.\d+|\d+|\D+)/ug) ?? [];
        const count = Math.min(t1.length, t2.length);
        let order = 0;
        for (let i = 0; order === 0 && i < count; ++i) {
            if (t1[i] !== t2[i]) {
                const n1 = Number.parseFloat(t1[i]);
                const n2 = Number.parseFloat(t2[i]);
                order = Number.isNaN(n1) || Number.isNaN(n2) ? compareStrings(t1[i], t2[i]) : compareNumbers(n1, n2);
            }
        }
        return order || compareNumbers(t1.length, t2.length);
    }
    return text1 < text2 ? -1 : 1;
}
export default compareStrings;