lodash/test/words.spec.ts

import assert from 'node:assert';
import lodashStable from 'lodash';
import { burredLetters, _, stubArray } from './utils';
import words from '../src/words';

describe('words', () => {
    it('should match words containing Latin Unicode letters', () => {
        const expected = lodashStable.map(burredLetters, (letter) => [letter]);

        const actual = lodashStable.map(burredLetters, (letter) => words(letter));

        assert.deepStrictEqual(actual, expected);
    });

    it('should support a `pattern`', () => {
        assert.deepStrictEqual(words('abcd', /ab|cd/g), ['ab', 'cd']);
        assert.deepStrictEqual(Array.from(words('abcd', 'ab|cd')), ['ab']);
    });

    it('should work with compound words', () => {
        assert.deepStrictEqual(words('12ft'), ['12', 'ft']);
        assert.deepStrictEqual(words('aeiouAreVowels'), ['aeiou', 'Are', 'Vowels']);
        assert.deepStrictEqual(words('enable 6h format'), ['enable', '6', 'h', 'format']);
        assert.deepStrictEqual(words('enable 24H format'), ['enable', '24', 'H', 'format']);
        assert.deepStrictEqual(words('isISO8601'), ['is', 'ISO', '8601']);
        assert.deepStrictEqual(words('LETTERSAeiouAreVowels'), [
            'LETTERS',
            'Aeiou',
            'Are',
            'Vowels',
        ]);
        assert.deepStrictEqual(words('tooLegit2Quit'), ['too', 'Legit', '2', 'Quit']);
        assert.deepStrictEqual(words('walk500Miles'), ['walk', '500', 'Miles']);
        assert.deepStrictEqual(words('xhr2Request'), ['xhr', '2', 'Request']);
        assert.deepStrictEqual(words('XMLHttp'), ['XML', 'Http']);
        assert.deepStrictEqual(words('XmlHTTP'), ['Xml', 'HTTP']);
        assert.deepStrictEqual(words('XmlHttp'), ['Xml', 'Http']);
    });

    it('should work with compound words containing diacritical marks', () => {
        assert.deepStrictEqual(words('LETTERSÆiouAreVowels'), ['LETTERS', 'Æiou', 'Are', 'Vowels']);
        assert.deepStrictEqual(words('æiouAreVowels'), ['æiou', 'Are', 'Vowels']);
        assert.deepStrictEqual(words('æiou2Consonants'), ['æiou', '2', 'Consonants']);
    });

    it('should not treat contractions as separate words', () => {
        const postfixes = ['d', 'll', 'm', 're', 's', 't', 've'];

        lodashStable.each(["'", '\u2019'], (apos) => {
            lodashStable.times(2, (index) => {
                const actual = lodashStable.map(postfixes, (postfix) => {
                    const string = `a b${apos}${postfix} c`;
                    return words(string[index ? 'toUpperCase' : 'toLowerCase']());
                });

                const expected = lodashStable.map(postfixes, (postfix) => {
                    const words = ['a', `b${apos}${postfix}`, 'c'];
                    return lodashStable.map(words, (word) =>
                        word[index ? 'toUpperCase' : 'toLowerCase'](),
                    );
                });

                assert.deepStrictEqual(actual, expected);
            });
        });
    });

    it('should not treat ordinal numbers as separate words', () => {
        const ordinals = ['1st', '2nd', '3rd', '4th'];

        lodashStable.times(2, (index) => {
            const expected = lodashStable.map(ordinals, (ordinal) => [
                ordinal[index ? 'toUpperCase' : 'toLowerCase'](),
            ]);

            const actual = lodashStable.map(expected, (expectedWords) => words(expectedWords[0]));

            assert.deepStrictEqual(actual, expected);
        });
    });

    it('should not treat mathematical operators as words', () => {
        const operators = ['\xac', '\xb1', '\xd7', '\xf7'],
            expected = lodashStable.map(operators, stubArray),
            actual = lodashStable.map(operators, words);

        assert.deepStrictEqual(actual, expected);
    });

    it('should not treat punctuation as words', () => {
        const marks = [
            '\u2012',
            '\u2013',
            '\u2014',
            '\u2015',
            '\u2024',
            '\u2025',
            '\u2026',
            '\u205d',
            '\u205e',
        ];

        const expected = lodashStable.map(marks, stubArray),
            actual = lodashStable.map(marks, words);

        assert.deepStrictEqual(actual, expected);
    });

    it('should prevent ReDoS', () => {
        const largeWordLen = 50000,
            largeWord = 'A'.repeat(largeWordLen),
            maxMs = 1000,
            startTime = lodashStable.now();

        assert.deepStrictEqual(words(`${largeWord}ÆiouAreVowels`), [
            largeWord,
            'Æiou',
            'Are',
            'Vowels',
        ]);

        const endTime = lodashStable.now(),
            timeSpent = endTime - startTime;

        assert.ok(timeSpent < maxMs, `operation took ${timeSpent}ms`);
    });
});