rel attribute validation does not account for dynamic value

[dominikg]

Describe the bug

Here

svelte/src/compiler/compile/nodes/Element.ts

Line 623 in df2e927

const rel_values = rel ? rel.get_static_value().split(' ') : [];

get_static_value() can return null and then null.split() happens.

Reproduction

https://svelte.dev/repl/b19472184dc6417fbcdc2077fc0593ee?version=3.52.0

Logs

8:57:24 PM [vite] Internal server error: Cannot read properties of null (reading 'split')
  Plugin: vite-plugin-svelte
  File: <snip>
      at Element.validate_special_cases (file:///home/dominikg/develop/sveltejs/svelte/compiler.mjs:20588:53)
      at Element.validate (file:///home/dominikg/develop/sveltejs/svelte/compiler.mjs:20350:9)
      at new Element (file:///home/dominikg/develop/sveltejs/svelte/compiler.mjs:20332:8)

System Info

System:
    OS: Linux 5.19 Manjaro Linux
    CPU: (16) x64 AMD Ryzen 9 5900HX with Radeon Graphics
    Memory: 47.34 GB / 62.21 GB
    Container: Yes
    Shell: 5.1.16 - /bin/bash
  Binaries:
    Node: 18.11.0 - ~/.local/share/pnpm/node
    Yarn: 1.22.19 - ~/.local/share/pnpm/yarn
    npm: 8.19.2 - ~/.local/share/pnpm/npm
  Browsers:
    Chromium: 107.0.5304.87
    Firefox: 106.0.2
  npmPackages:
    rollup: ^1.27.14 => 1.27.14

Severity

blocking an upgrade

[sheodox]

I'm running into the same issue doing something similar, just moved the string out to a const and am using it in more than one place so I don't typo noreferrer noopener.

https://svelte.dev/repl/53108f89a65b4342b14eb5fdcb9b310d?version=3.52.0

[Conduitry]

Fixed in 3.53.1 - https://svelte.dev/repl/b19472184dc6417fbcdc2077fc0593ee?version=3.53.1 - thanks for the PR!