Failed to compile

[taoqf]

Bug report

Describe the bug

A clear and concise description of what the bug is.

Error: xxx:Invalid page config export found. Expected object but got TSAsExpression in file /src/pages/index.tsx. See: https://err.sh/vercel/next.js/invalid-page-config

To Reproduce

Steps to reproduce the behavior, please provide code snippets or a repository:

1. Create page index.tsx
2. Add page component.
3. Add page config like this:

import { PageConfig } from 'next';
export const config = {
} as PageConfig;

4. See error
5. Change the config to:

export const config: PageConfig = {
};

6. Error is gone.

Expected behavior

A clear and concise description of what you expected to happen.

Screenshots

If applicable, add screenshots to help explain your problem.

System information

• OS: Debian
• Browser (if applies) Chromium
• Version of Next.js: 10.0.4
• Version of Node.js: 15.5.0
• Develop: next dev
• TypeScript:4.1.3

Additional context

Add any other context about the problem here.

[lachlanjc]

I don't know how Typescript is playing into this, but the error mentions that the config object can't be dynamically modified: https://github.com/vercel/next.js/blob/master/errors/invalid-page-config.md#possible-ways-to-fix-it

[taoqf]

I tried compile them with ts, and the compiled js is exactly same.

a.ts

import { PageConfig } from 'next';

export const config = {
} as PageConfig;

b.ts

import { PageConfig } from 'next';

export const config: PageConfig = {
};

a.js

"use strict";
exports.__esModule = true;
exports.config = void 0;
exports.config = {};

b.js

"use strict";
exports.__esModule = true;
exports.config = void 0;
exports.config = {};

[github-actions]

This closed issue has been automatically locked because it had no new activity for a month. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.