utf8-decoder

utf8-decoder

A simple UTF-8 decoder, keeping align with native TextDecoder as much as possible.

Most part of the code is modified from V8's Utf8DfaDecoder, which is a modified version of Flexible and Economical UTF-8 Decoder.

• Handle malformed UTF-8 better than most solutions.
• Produce same output as the Node's TextDecoder.
• Keep default char unicode � as-is instead of throwing error.
• Process surrogate pairs correctly for Emojis.
• Designed with performance in mind. Provide comparable performance to native TextDecoder.

You can try over the test case for other UTF-8 decoders to see the difference, especially the malformed cases.

Usage

Install package:

# ✨ Auto-detect
npx nypm install utf8-decoder

# npm
npm install utf8-decoder

# yarn
yarn add utf8-decoder

# pnpm
pnpm install utf8-decoder

# bun
bun install utf8-decoder

Import:

ESM (Node.js, Bun)

import { decode } from "utf8-decoder";

CommonJS (Legacy Node.js)

const { decode } = require("utf8-decoder");

CDN (Deno, Bun and Browsers)

import { decode } from "https://esm.sh/utf8-decoder";

Development

local development

• Clone this repository
• Install latest LTS version of Node.js
• Enable Corepack using corepack enable
• Install dependencies using pnpm install
• Run interactive tests using pnpm dev

Reference

Unicode/UTF-8 is a complex topic, here are some references for further reading:

• UTF-8 Encoding
• The Unicode Standard

I recommend reading the chapter 3 of the Unicode Standard for a better understanding of the encoding and the invalid sequences and error handling.

This project is highly inspired by the following projects:

• V8's Utf8DfaDecoder
• Flexible and Economical UTF-8 Decoder
• TextDecoder
• TextEncoding

License

Published under the MIT license. Made by community 💛

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