Breakpoint on initial render not being called on rerender

[JorgeRey-Lenio]

Describe the bug

Hi!

While trying Vite on a React Project and debugging it I found that if you add a breakpoint (on the browser inspector) on a useEffect with an empty array of dependencies it won't be triggered when you force a Hot Reload, but the code is being executed. For example, if you add a console log in the useEffect you will see the Log in the console when you trigger a reload but the breakpoint is not called.

I leave an example on stackblitz.

Thanks!

Reproduction

https://stackblitz.com/edit/vitejs-vite-mlud4j

Steps to reproduce

Just put a breakpoint on the console log inside the useEffect and modify the content of the string to force a hot reload.

System Info

System:
    OS: Linux 5.0 undefined
    CPU: (8) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
    Memory: 0 Bytes / 0 Bytes
    Shell: 1.0 - /bin/jsh
  Binaries:
    Node: 16.14.2 - /usr/local/bin/node
    Yarn: 1.22.19 - /usr/local/bin/yarn
    npm: 9.4.2 - /usr/local/bin/npm
  npmPackages:
    @vitejs/plugin-react: ^4.0.0 => 4.0.0 
    vite: ^4.3.9 => 4.3.9

Used Package Manager

npm

Logs

No response

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Make sure this is a Vite issue and not a framework-specific issue.
• Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.
• The provided reproduction is a minimal reproducible example of the bug.

[ArnaudBarre]

The issue is that after fast refresh, the file is different from the point of view of the browser because of the querystring.

I need to investigate but this might be tricky to fix given how Vite HMR works currently.

@bmeurer maybe you have a different view on this?

[patak-cat]

Somewhat related vitejs/vite#13503 (comment)

[bmeurer]

I suspect that this is a different problem than vitejs/vite#13503. I think what we're seeing here is that the migration of the breakpoint is racing with the execution of the useEffect closure.

cc @jaro-sevcik @natorion

[ArnaudBarre]

Does bumping the timeout here helps?

[bmeurer]

I just checked with Firefox 102.11.0esr (64-bit), which also misses the breakpoint.

Bumping the timeout will likely make this more likely to work, but it'd still be flakily missing the breakpoint, since it's still racy.

[bmeurer]

One workaround that will always work: Put a debugger statement there instead of a breakpoint.

[ArnaudBarre]

I'm closing this issue to cleanup because there is not a lot that can be done here and a fix will need to come from a better operability between the debuggers and Vite core. @sapphi-red already merged some PR in that direction: vitejs/vite#13514