index_test.js

import test from 'ava';
import {re} from '../esm/index.js';

test('Composing regular expressions', t => {
    const RE_YEAR = /([0-9]{4})/;
    const RE_MONTH = /([0-9]{2})/;
    const RE_DAY = /([0-9]{2})/;
    const RE_DATE = re`/^${RE_YEAR}-${RE_MONTH}-${RE_DAY}$/u`;
    t.is(RE_DATE.source, '^([0-9]{4})-([0-9]{2})-([0-9]{2})$');
});
test('Setting flags', t => {
    const regexp1 = re`/abc/gu`;
    t.true(regexp1 instanceof RegExp);
    t.is(regexp1.source, 'abc');
    t.is(regexp1.flags, 'gu');

    const regexp2 = re`/xyz/`;
    t.true(regexp2 instanceof RegExp);
    t.is(regexp2.source, 'xyz');
    t.is(regexp2.flags, '');
});
test('Computed flags', t => {
    const regexp = re`/abc/${'g'+'u'}`;
    t.true(regexp instanceof RegExp);
    t.is(regexp.source, 'abc');
    t.is(regexp.flags, 'gu');
});
test('Simple, flag-less mode', t => {
    const regexp = re`abc`;
    t.true(regexp instanceof RegExp);
    t.is(regexp.source, 'abc');
    t.is(regexp.flags, '');
});
test('Escaping special characters in strings', t => {
    t.is(re`/-${'.'}-/u`.source, '-\\.-');
});
test('Use “raw” backslashes like in regular expressions', t => {
    t.is(re`/\./u`.source, '\\.');
});
test('Slashes don’t need to be escaped', t => {
    t.true(re`/^/$/u`.test('/'));
});
test('Escaping backticks', t => {
    // Must escape in static text:
    const RE_BACKTICK = re`/^\`$/u`;
    t.is(RE_BACKTICK.source, '^`$');
    t.true(RE_BACKTICK.test('`'));
    // No escaping of backticks in dynamic text:
    const str = '`\\`';
    t.is(re`/${str}/`.source, '`\\\\`');
        // Single backslash in `str` is escaped inside regular expression
});