Make VIRTUAL_PREFIX configurable

[marpe]

I'm using this in the development of a chrome web extension and am receiving this error:

Cannot load extension with file or directory name __vue-router. Filenames starting with "_" are reserved for use by the system.
Could not load manifest.

So it would be nice to be able to configure the VIRTUAL_PREFIX or maybe opt for another default?

[posva]

That looks like a weird limitation. In the end, there is no file named that way It's just a virtual file that is handled by the dev server. Other libraries like uno.css does this as well

It would be helpful to see how this error is produced

[marpe]

Removed my node_modules which I had patched, and tried to recreate it, but haven't been able to. First time using vue/vite and using a template which already have a bunch configured, so very likely I had something misconfigured at one point (I definitely saw a folder named __something in the build output :P).

You can close this and I'll make sure to include a reproducible example if I run into it again.

[jods4]

@posva please note that changing VIRTUAL_PREFIX is a breaking change, that should be announced when released.
I think the "internal" module name needs to be documented and considered stable.

Example of places where we depend on the name __vue-router/auto-routes:

• Whitelisting the module in other Vite plugins config. Specifically our routes meta contain unocss icon names, so we whitelisted __vue-router/auto-routes in UnoCSS include config.
• Handling HMR updates of the route table: import.meta.hot.accept("__vue-router/auto-routes", ...)

[posva]

I'm more worried that you have to depend on the internal virtual representation of the module that is only needed in order to write the plugin for vite 😓, I wouldn't even use such representation if it wasn't required by the bundlers implementations. I see that as a bug here, or a design issue in vite, or as a bug in unocss, but I don't know where. Which also means that it will probably change again to fix issues. Although you could use .endsWith('vue-router/auto-routes') thought, that should cover any prefixes.

The reason behind the change was needed to support HMR. I worked on this with the help of antfu and followed some of the design choices made in unocss. The documentation on HMR on vite wasn't really effective neither was this article. I think this is specific to the virtual module though...

[jods4]

Yeah, we actually used the glob **/auto-routes in UnoCSS include config, precisely because I felt uncomfortable with this undocumented prefix.

I agree 100% that the design feels off.
Not sure what the better way would be, but the intuitive thing is to include: "vue-router/auto-routes", which is how the module is named in JS/TS code. That does not work, but ideally I think it should.