Issue error if readonly static property has no initializer

[Trias]

Bug Report

🔎 Search Terms

static property readonly undefined typecheck literal

🕗 Version & Regression Information

As far as i know this is the behavior of all typescript version, but i think it's not intuitive

⏯ Playground Link

See my Playground example:

https://www.typescriptlang.org/play?#code/KYDwDg9gTgLgBAYwDYEMDOa4BVhpgYWimAXgG8BYAKDlrjxRgEsE5iUATCAOyQE96EALbAAcihFwAvHABEaYWInBZAbmoBfatVCRYiVBmy4YAISgQA1sG5xKNOg2at2XXgIUjxIgFxzPSiJqmtpUOHiEUMSkAHQB3sDqVNRMAGZwABThZhbW3HGKCdIy8oXKsgCU9nSIPApIwDFIEADmGQAGAK4QADRwTADkQnCd3OwIABYoAEYNMXAAgkgKcDATwKt8YBsQ6dnmVjYFXsr9mAOlJ0EDfQDu68T98GgTEJ1IHHDTG4xwDejwAZ4KBMbgtOAAHxG3A4wFSoOAHAGcGgbEYDzgA1GsPh3ERA3aFU0QA

💻 Code

export class TestCorrect {
    static readonly someName = "someName";
}

export class TestBroken {
     static readonly someName: "someName"; 
     //  spot the error? ----^  
     // note how similar the syntax looks to the class above. 
     // but this time we are declaring a literal type and also prevent any assignment. which makes little sense and is likely a bug. 
     // what was meant is probably the code above.
}

if (TestBroken.someName == "someName") {
    console.log(`uo, i'm unreachable. Also the type of TestBroken.someName is `"someName"`, where it should rather be `undefined` or an error at the class definition)
}

🙁 Actual behavior

the code is accepted by typescript

🙂 Expected behavior

either an error at TestBroken-class or a type inference of "someName" | undefined (first option preferred)

[Trias]

I'm willing to invest some time in this if you agree that it's a bug and how it should be fixed :)

[MartinJohns]

Duplicate of #27899. At least when ignoring the read-only.

[Trias]

@MartinJohns thanks! I think for the mutable version it would be hard for typescript to determine if the property gets initialized somewhere, but it could be typed as "literal" | undefined in that case. And if strictPropertyInitialization is enabled or readonly is specified it should require a static assignment in my opinion.