Dev server files are not loaded with base path

[andycarlberg]

Describe the bug

I'm using a code-server cloud environment to develop a SvelteKit project. In order to access the dev server, a proxy is provided that uses a subpath to proxy the dev server port (see docs). This leads me to need a base path to be set for the dev server.

If I set a base path as stated in the documentation, the first page load works correctly but the import statements on the rendered page are relative to the root. These return a 404, correctly, because those files are not available without the proxy.

Related to sveltejs/kit#2958

Expected behavior
All paths in the dev server reference the base path instead of being relative to the root domain. If necessary, the dev server strips the base path to find the dev server files.

Reproduction

1. Create a new Vite project
2. Set base path to a non-root path
3. Run the dev server

System Info

System:
    OS: Linux 5.10 Ubuntu 20.04.3 LTS (Focal Fossa)
    CPU: (12) x64 Intel(R) Core(TM) i5-10400 CPU @ 2.90GHz
    Memory: 560.98 MB / 15.32 GB
    Container: Yes
    Shell: Unknown - /bin/false
  Binaries:
    Node: 14.18.2 - /usr/bin/node
    Yarn: 1.22.15 - /usr/bin/yarn
    npm: 6.14.15 - /usr/bin/npm
  npmPackages:
    vite: ^2.6.14 => 2.6.14

Used Package Manager

npm

Logs

No response

Validations

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• The provided reproduction is a minimal reproducible example of the bug.

[Bastian]

Since I ran into the same issue with Svelte-Kit, I don't quite understand why you believe that this is a Vite problem.
With the following vite.config.ts in a Vanilla-TS Vite (v2.7.2) project, everything works like I would expect it:

import { defineConfig } from 'vite';

// https://vitejs.dev/config/
export default defineConfig({
    base: '/base-path/',
});

Am I missing something?

[andycarlberg]

No, agreed, I must have been doing something wrong before. This doesn't seem to be a Vite issue. I'm fairly new to Vite and I must have configured something incorrectly before. I am seeing the behavior work correctly in a vanilla Vite project.