README.md

TextEncoder Polyfill

A C++ implementation of the WHATWG Encoding API TextEncoder interface for use in Babylon Native JavaScript runtimes via Napi.

This is the encoding counterpart to the TextDecoder polyfill in this same repository. Both polyfills exist primarily for older Chakra-based runtimes where the WHATWG Encoding Standard globals are not built in. On modern V8 / JSC / Hermes runtimes the constructor is already exposed and Initialize() is a no-op.

Current State

Supported

• Constructing TextEncoder with no argument (UTF-8 is the only encoding the spec mandates).
• The encoding accessor (always returns "utf-8").
• encode(input) — returns a Uint8Array containing the UTF-8 bytes of input. Calling with no argument or undefined returns an empty Uint8Array (matches the spec, which defaults input to "").

Not Supported

• Encodings other than UTF-8 — the TextEncoder constructor in the spec only accepts UTF-8 anyway, so this is not a deviation.
• encodeInto(source, destination) — not implemented. Babylon.js does not call this entry point; the (substantially more involved) UTF-16-code-unit accounting it would require is not justified by any current consumer. If a future consumer needs it, it can be added at that time.

Usage

const encoder = new TextEncoder();
encoder.encoding;                 // "utf-8"

encoder.encode("Hello");          // Uint8Array(5) [72,101,108,108,111]
encoder.encode();                 // Uint8Array(0) []