Async element handler throws - Cannot read properties of undefined (reading 'asyncify_get_state')

[paed01]

Hi, and thank you for a fantastic library. Immensely helpful when unit testing our worker before deploying to Cloudflare.

According to the official docs async element handlers are supported. But when we attempt to use one during testing we get an error.

This snippet:

import { HTMLRewriter } from 'htmlrewriter'

const rewriter = new HTMLRewriter()

async function main() {
    rewriter.on('a', {
        async element(element) {
            await new Promise((resolve) => {
                element.setAttribute('href', 'https://www.baidu.com');
                resolve();
            });
        },
    })
    const res = await rewriter.transform(
        new Response('<a href="https://www.google.com">google</a>'),
    )
    console.log(await res.text())
}

main()

throws:

file:///app/node_modules/htmlrewriter/dist/asyncify.js:77
    if (wasm.asyncify_get_state() === State.REWINDING) {
             ^

TypeError: Cannot read properties of undefined (reading 'asyncify_get_state')
    at awaitPromise (file:///app/node_modules/htmlrewriter/dist/asyncify.js:77:14)
    at imports.wbg.__wbg_awaitPromise_39a1101fd8518869 (file:///app/node_modules/htmlrewriter/dist/html_rewriter.js:814:9)
    at wasm://wasm/0036341a:wasm-function[250]:0x7da04
    at wasm://wasm/0036341a:wasm-function[70]:0x32ee6
    at wasm://wasm/0036341a:wasm-function[47]:0x18162
    at wasm://wasm/0036341a:wasm-function[86]:0x3bd2c
    at wasm://wasm/0036341a:wasm-function[185]:0x6109a
    at wasm://wasm/0036341a:wasm-function[160]:0x5a5c1
    at wasm://wasm/0036341a:wasm-function[386]:0x92305
    at HTMLRewriter.write (file:///app/node_modules/htmlrewriter/dist/html_rewriter.js:665:14)

Are we doing something wrong or are async handlers not supported by this package?

Best regards.