Host.arrayBufferToBase64 panics

[mhmd-azeez]

Repro:

export function greet() {
  const base64String = "SGVsbG8g8J+MjSBXb3JsZCHwn4yN";

  console.log('decoding string:', base64String);

  const decodedBuffer = Host.base64ToArrayBuffer(base64String);
  const decodedString = new TextDecoder().decode(decodedBuffer);

  console.log('decoded string:', decodedString);

  const encodedBuffer = Host.arrayBufferToBase64(decodedBuffer);
  
  console.log('encoded string:', encodedBuffer);

  Host.outputString(`Hello, ${Host.inputString()}`)
}

v1.3.3:

mo@mo-dylibso:/mnt/d/x/extism/ts_plugin$ extism-js --version
extism-js 1.3.3
mo@mo-dylibso:/mnt/d/x/extism/ts_plugin$ npm run build && npm run test

> [email protected] build
> tsc --noEmit && node esbuild.js && extism-js dist/index.js -i src/index.d.ts -o dist/plugin.wasm


> [email protected] test
> extism call dist/plugin.wasm greet --input 'Mo' --wasi --log-level debug

2025/01/12 19:57:17 Calling function : greet
2025/01/12 19:57:17 decoding string: SGVsbG8g8J+MjSBXb3JsZCHwn4yN
2025/01/12 19:57:17 decoded string: Hello 🌍 World!🌍
Error: wasm error: unreachable
wasm stack trace:
        .$1363(i32,i32,i32,i32,i32)
        .$1496(i32,i32)
        .$1487(i32,i32,i32)
        .$1513(i32)
        .$217(i32,i32) i32
        .$1567(i32) i32
        .$1584() i32
returned non-zero exit code: 1

v1.2.0:

mo@mo-dylibso:/mnt/d/x/extism/ts_plugin$ extism-js --version
extism-js 1.2.0
mo@mo-dylibso:/mnt/d/x/extism/ts_plugin$ npm run build && npm run test

> [email protected] build
> tsc --noEmit && node esbuild.js && extism-js dist/index.js -i src/index.d.ts -o dist/plugin.wasm


> [email protected] test
> extism call dist/plugin.wasm greet --input 'Mo' --wasi --log-level debug

2025/01/12 19:59:05 Calling function : greet
2025/01/12 19:59:05 decoding string: SGVsbG8g8J+MjSBXb3JsZCHwn4yN
2025/01/12 19:59:05 decoded string: Hello 🌍 World!🌍
2025/01/12 19:59:05 encoded string: SGVsbG8g8J+MjSBXb3JsZCHwn4yN
Hello, Mo

[mhmd-azeez]

See https://github.com/dylibso/xtp-typescript-bindgen/actions/runs/12733723565/job/35490419178