HMR does not reload changes in default props

[chawes13]

Describe the bug

I am changing the value of a default prop and seeing subsequent "hmr update" logs in the terminal. The new value of the prop does not show up in the component when no value is passed for the prop to the component (i.e., the default is used).

Reproduction

https://stackblitz.com/edit/vitejs-vite-velxyz?file=src%2FApp.jsx

Steps to reproduce

1. Update the value of title in defaultProps
2. Save
3. New value of title is not shown in the <h1>

System Info

System:
    OS: Linux 5.0 undefined
    CPU: (4) 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:
    @vitejs/plugin-react: ^4.3.1 => 4.3.1 
    vite: ^5.3.4 => 5.3.4

Used Package Manager

npm

Logs

No response

Validations

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• Read the Contributing Guidelines.
• Read the docs.
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• The provided reproduction is a minimal reproducible example of the bug.

[ArnaudBarre]

This is something that should be handled at the Fast Refresh level, but it's not and probably never will be because fast refresh was released in 2019, 4 years after default parameters have been a thing in the language. I'm quite impressed that this as not been deprecated yet.

You should rewrite your code like this

function App({ title = 'Vite + React (test)!' }) {

and also consider using TS:

function App({ title = 'Vite + React (test)!' }: { title?: string }) {

[chawes13]

Company constraints 🤷 . It works with Webpack, so it's a bit annoying to introduce this regression when switching build tools. Given that defaultProps are getting deprecated in v19, I'll move over to default parameters.