locutus/esm/ruby/String/gsub.js

Locutus other languages' standard libraries to JavaScript for fun and educational purposes

export function gsub(str, pattern, replacement) {
    // parity verified: Ruby 3.3
    //      discuss at: https://locutus.io/ruby/String/gsub/
    //     original by: Kevin van Zonneveld (https://kvz.io)
    //          note 1: Global substitution across the entire string.
    //       example 1: gsub('hello world', 'l', 'L')
    //       returns 1: 'heLLo worLd'
    //       example 2: gsub('abcabc', 'ab', '#')
    //       returns 2: '#c#c'
    //       example 3: gsub('foo', 'x', 'y')
    //       returns 3: 'foo'
    const source = String(str);
    const replacementText = String(replacement);
    if (pattern instanceof RegExp) {
        const flags = pattern.flags.includes('g') ? pattern.flags : `${pattern.flags}g`;
        return source.replace(new RegExp(pattern.source, flags), replacementText);
    }
    const needle = String(pattern);
    if (needle === '') {
        return source;
    }
    return source.replaceAll(needle, replacementText);
}