ReferenceError: Can't find variable: TextDecoder

TextDecoder.md

Error:

Using expo react-native and realm-web for iOS etc

ReferenceError: Can't find variable: TextDecoder

Solution:

Install dependencies

expo install text-encoding big-integer

Create polyfill file at polyfills/TextEncoding.js

import TextEncodingPolyfill from 'text-encoding';
import BigInt from 'big-integer';
Object.assign(global, {
    TextEncoder: TextEncodingPolyfill.TextEncoder,
    TextDecoder: TextEncodingPolyfill.TextDecoder,
    BigInt: BigInt,
});

Update index.js (if you have one) or App.js with the following at the top

import "./polyfills/TextEncoding";

Note: Using Babel for polyfills means you have to eject. So do this instead.

Restart expo using expo start -c -i

iOS should now boot.