SvelteKit demo app 'todos' failing on delete

Describe the bug The SvelteKit demo app seems to have a bug when deleting ‘todos’. It occurs when multiple todos are added and subsequently deleted.

Logs

--- Browser log
Failed to load resource: the server responded with a status of 500 (Internal Server Error)
{"status":500,"message":"Error deleting todo"}

Server log has no error messages

To Reproduce

• Create a new SvelteKit demo app (npm init svelte@next app-dir), accepting all the defaults
• cd app-dir
• npm i
• npm run dev – --open
• Open devtools

Perform the following steps (You may experience the error prior to completing all steps):

• Navigate to TODOS, enter 3 TODOS.
• Delete first TODO
• Delete last TODO
• Delete remaining TODO
• Enter 3 TODOs again
• Delete first TODO
• Delete last TODO

Expected behavior TODO’s are deleted when requested

Diagnostics

System:
    OS: Linux 5.8 Ubuntu 20.04.2 LTS (Focal Fossa)
    CPU: (6) x64 Intel(R) Core(TM) i5-8400 CPU @ 2.80GHz
    Memory: 25.99 GB / 31.04 GB
    Container: Yes
    Shell: 5.0.17 - /bin/bash
  Binaries:
    Node: 14.17.0 - /usr/bin/node
    Yarn: 1.22.10 - /usr/local/bin/yarn
    npm: 7.12.0 - /usr/local/bin/npm
  Browsers:
    Brave Browser: 90.1.24.85
    Chrome: 90.0.4430.212
    Firefox: 88.0.1
  npmPackages:
    @sveltejs/kit: next => 1.0.0-next.109 
    svelte: ^3.34.0 => 3.38.2 

using Chrome (also fails using Firefox)

no adapter specified

Severity Not severe. It may affect user perception of stability when evaluating SvelteKit.

Additional context Failure is also present when running on Windows.

[hb0nes]

I just wanted to comment here that I almost quit investing more time into SvelteKit because the Todo’s really seem slow and wonky.

I can just click randomly on the Todo’s until it ‘breaks’. When it breaks, it will check the Todo but then after a second or more, change its mind again.

I don’t know, it’s just very bad/wonky UX.

Seeing as it’s one of the first thing new devs picking up Svelte will see, this is bad news.

[denniske]

I was checking out sveltekit today and the laggy experience of the todos page put me off. After changing it to an in memory store in /todos/index.ts the response times of the api requests went from 300+ ms to ~5ms. I think this should be the default experience for new sveltekit users.

If the external api todos page is needed for showing features of sveltekit, I would suggest to make two todos pages (one with in memory and one with external api).