TypeError: Cannot read properties of undefined (reading 'Symbol(Symbol.metadata)')

[mmzhangliyang]

I use colyseus 0.16.4, and I had an Error.

My Schema Define like this

When I debug my program, I found that the 'MapSchema' instance has an 'undefined' [$childType] property.
I think the Schema definition is right, I use this definition in another project, it works well.
but in this project, it works with an Error.
my package.json:

Did I use something wrong somewhere?
Please help me. Thank you very much
I realy like Colyseus !

[endel]

Hi @mmzhangliyang, I hope you are well! Which version of @colyseus/schema is listed in your lockfile? (package-lock.json)

I'd suggest to try upgrading @colyseus/schema to latest version (3.0.39) as this issue might've been fixed already.

If the issue persists I will ask you to provide a small isolated repository that reproduces the issue so I can take a look!

Cheers

[mmzhangliyang]

Hi there, Thanks a lot for your reply.
I have confirmed that the version of @colyseus/schema is 3.0.39. and the error still exists.
and here is my small project,I attached here.
Server.zip

[endel]

Thanks for sharing. You need to add "useDefineForClassFields": false to your tsconfig.json file.

This config is required because of how @colyseus/schema uses property descriptors in classes in conjunction to JavaScript's legacy decorators.

[mmzhangliyang]

Thank you so much for your assistance.
It is my fault.
Best wishes for you!
Best wishes for Colyseus!

[CrimsonBolt47]

hi i do have "useDefineForClassFields": false but i still have this issue.
this is my tsconfig.json
{
"compilerOptions": {
"outDir": "build",
"target": "ESNext",
"module": "CommonJS",
"moduleResolution": "node",
"strict": true,
"allowJs": true,
"strictNullChecks": false,
"esModuleInterop": true,
"experimentalDecorators": true,
"skipLibCheck": true,
"forceConsistentCasingInFileNames": true,
"useDefineForClassFields": false
},
"include": [
"src"
]
}
i am using latest versions of colyseus in both client and server
please help