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Bug: breakpoints are not hit after rebuilding the project [vite]

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#383 2 comments 2 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
42/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
typescript, vite
Domain
devtools

Research direction

Reproduce the issue with the provided Vite sourcemap configuration and Firefox launch settings, rebuilding through vite dev while observing breakpoint behavior. Inspect how timestamped and retained Vite sources are handled, and consider the issue done when breakpoints remain hit and correctly resolved after rebuilding in Firefox, VS Code, and Neovim.

Written by the indexing model from the issue text.

Description

Related #362

After enabling sourcemap for vite (see below), I can consistently hit breakpoints, and their locations will be resolved correctly.

export default defineConfig({
    plugins: [sveltekit()], // svelte specific stuff, your config might be different
    build: {
        sourcemap: true
    }
});

However, once I rebuild the project (via vite dev), breakpoints are no longer hit. No wrong locations, no phantom breakpoints, just not hit at all.

I do wanna stress that rebuilding is something that happens constantly during development, so it should be supported (if possible).

After some investigation, I found out that vite appends a timestamp to the sources (and it also keeps old copies), which can be seen in FF's debugger (screenshot below):

Image

I wonder if it's related?

More info

Launch config:

    {
      "name": "Launch Firefox",
      "type": "firefox",
      "suggestPathMappingWizard": true,
      "reAttach": true,
      "request": "launch",
      "url": "http://localhost:5173/",
      "webRoot": "${workspaceFolder}"
    }

The same issue happens on neovim and vscode, so it's not client-side related.

Dominant language
TypeScript
Stars
446
Forks
77
No merged PRs in 30d

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