Bug: React Router 7 Loader Fails When Response Contains Invalid Date Objects

[hezki]

I'm using React Router as a...

library

Reproduction

export async function loader() { return { invalidDateField: new Date('invalid-date-string') }; }

https://stackblitz.com/edit/github-rxhk6sn1-zaw2xuan?file=app%2Froutes%2Fhome.tsx

System Info

System:
    OS: Linux 5.0 undefined
    CPU: (2) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
    Memory: 0 Bytes / 0 Bytes
    Shell: 1.0 - /bin/jsh
  Binaries:
    Node: 18.20.3 - /usr/local/bin/node
    Yarn: 1.22.19 - /usr/local/bin/yarn
    npm: 10.2.3 - /usr/local/bin/npm
    pnpm: 8.15.6 - /usr/local/bin/pnpm
  npmPackages:
    @react-router/dev: * => 7.4.0 
    @react-router/node: * => 7.4.0 
    @react-router/serve: * => 7.4.0 
    react-router: * => 7.4.0 
    vite: ^6.0.11 => 6.2.2

Used Package Manager

npm

Expected Behavior

{"siteTitle":"React Router","bug":null}

The loader function should handle Invalid Date objects in the same way as standard JSON.stringify, i.e., convert them to null and not cause a syntax error.

Actual Behavior

Oops! Unable to decode turbo-stream response

Additional Information

The issue seems to arise from how React Router handles the serialization of data returned from the loader. When performing JSON.stringify on an object containing an Invalid Date, the expected result is that the Invalid Date would be converted to null, but this bug causes a syntax error on the client side.

Possible Solution

React Router should ensure that handling invalid date objects matches the standard behavior of JSON.stringify or provide an alternative solution that prevents the application from crashing in such cases.

[kevlened]

This is an issue in turbo-stream v2: jacob-ebey/turbo-stream#55

It's resolved in v3, but react-router hasn't been upgraded to v3 yet: #12945