Update polyfills.js to include File

[ConProgramming]

Currently there is no global File object available. Usually this is fine, as any "file" returned by FormData still has the normal properties and methods available.

The problem became apparent when using zod-form-data, a library that relies on the global File object.

import { zfd } from "zod-form-data";

const schema = zfd.formData({
    pdf: zfd.file(),
});

Discussion here.

This is a simple fix, just adds another import from undici to include File.

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[dummdidumm]

Makes sense to me. Could you please do the File export from undici and provide a changeset?

[ConProgramming]

Makes sense to me. Could you please do the File export from undici and provide a changeset?

That was my original solution, but actually this is the FormData of undici.

const { File: UndiciFile, FileLike, isFileLike } = require('./file')
const { Blob, File: NativeFile } = require('buffer')
/** @type {globalThis['File']} */
const File = NativeFile ?? UndiciFile

In node environments like SvelteKit, it'll use the native node File from buffer.

I'll add the changeset though.

[dummdidumm]

You have to use the import from undici. As you can see from all the CI test failures, File doesn't exist on buffer in Node16.

[ConProgramming]

You have to use the import from undici. As you can see from all the CI test failures, File doesn't exist on buffer in Node16.

Hm well we'd have to do it conditionally like undici does right? Or else there'd be type mismatch between the global File and what is returned by the undici FormData.

const { File: UndiciFile, FileLike, isFileLike } = require('./file')
const { Blob, File: NativeFile } = require('buffer')
/** @type {globalThis['File']} */
const File = NativeFile ?? UndiciFile

On Node16 unidici uses UndiciFile but on Node18 it usesNativeFile.

Is this possible currently, since installPolyfills is ESM?

[ConProgramming]

Works for my uses. Thanks!

I guess then tree shaking doesn't matter for built in node modules?

[dummdidumm]

Thank you!