[TS] `DocumentFiles` is not exported from `_document.tsx`

Feature request

Is your feature request related to a problem? Please describe.

I’m trying to use DocumentFiles like:

getCssLinks({ allFiles }: DocumentFiles) {
	const { assetPrefix } = this.context
	if (!allFiles || allFiles.length === 0) return null

	return allFiles
		.filter((file: any) => /\.css$/.test(file))
		.map((file: any) => (
			<style
				key={file}
				nonce={this.props.nonce}
				data-href={`${assetPrefix}/_next/${file}`}
				dangerouslySetInnerHTML={{
					__html: fs.readFileSync(path.join(process.cwd(), '.next', file), 'utf-8'),
				}}
			/>
		))
}

Describe the solution you’d like

Just have to export DocumentFiles from https://github.com/vercel/next.js/blob/canary/packages/next/pages/_document.tsx#L47

Describe alternatives you’ve considered

I use any like so:

getCssLinks({ allFiles }: { allFiles: any }) {
	...
}

Additional context

I’ve written about it here → https://github.com/vercel/next-plugins/issues/238#issuecomment-699890100

[timneutkens]

DocumentFiles is not a public property. Overriding built-in components is not recommended and is likely to break between upgrading Next.js versions.

[balazsorban44]

This issue has been automatically locked due to no recent activity. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.