Wrong elementwise error location on optional object property that allows arrays too

🔎 Search Terms

error location elementwise elaboration array optional object

🕗 Version & Regression Information

• This is a crash
• This changed between versions ______ and _______
• This changed in commit or PR _______
• This is the behavior in every version I tried, and I reviewed the FAQ for entries about _________
• I was unable to test this on prior versions because _______

⏯ Playground Link

https://www.typescriptlang.org/play?ts=5.5.0-dev.20240225#code/C4TwDgpgBAyglgOwOYBsIHkBOBBTmCGIAPACoB8UAvFCVAD5SYT4AmA9giiDQNoC6AbgBQQ0JCgAFTGwBucFhBbYAxsDaYqUAN5CoUAM6ZlALgPBMiJML2IwAV2AB+U3YQBrBGwDuCYQF9hUXBoAFl8ZQALRAgAYQ4AMzgkUhU1TH0oCAAPYAgEFgypWXlFVPUKah0bBBk2NwhnWEs0LFwCYhIy9LJ-QIVlFHwmKHjXVTgOAwhgOzAU1XUM7Nz8wuk5BSUFzDIACgBKUyqoZSZ8XLDI6NNd5QSk00uohFj75M7t-TJ9qgpa+V6In001mRC0BiMpgARPFppEAKrAzBQgRQWwOUz6cyWKB+Pb7AB0p2YF3Czwgu2OiFq9SOuj0EJMUBhcIiiIgyIANPTqvZgKYAIwABm5ej83L8+2EQA

💻 Code

type SingleOrArray<T> = T | readonly T[];

type ProvidedActor = {
  src: string;
  input?: unknown;
};

type MachineConfig<TActors extends ProvidedActor> = {
  invoke?: SingleOrArray<TActors>;
};

declare function setup<TActors extends ProvidedActor>(): {
  createMachine: (config: MachineConfig<TActors>) => void;
};

setup<{ src: "fetchUser"; input: string }>().createMachine({
  invoke: {
    src: "fetchUser",
    input: 10,
  },
});

🙁 Actual behavior

invoke property gets highlighted

🙂 Expected behavior

input property should get highlighted as it's the one that it's not correct and it's more specific than invoke

Additional information about the issue

we can observe the error location to change when:

1. we remove optionality from invoke
2. we make the provided type argument a union

Beginne mit dem verlinkten TypeScript Playground und der bereitgestellten generischen setup/createMachine-Reproduktion und untersuche dann, wie der Checker eine Fehlerposition für die optionale invoke-Eigenschaft und ihre input-Eigenschaft auswählt. Abgeschlossen ist die Aufgabe, wenn die Diagnose input statt invoke hervorhebt und dabei das erwartete Verhalten für die erwähnten optionalen und Union-Varianten beibehält.