Infering by nested kind

[jozefchutka]

Bug Report

🔎 Search Terms

infer, kind, nested

🕗 Version & Regression Information

• This is the behavior in every version I tried

⏯ Playground Link

Playground link with relevant code

💻 Code

type MyObject =  {
	readonly kind:{kind:"a";};
  readonly a:string;
} | {
	readonly kind:{kind:"b";};
}

const create = ():MyObject => ({a:"", kind:{kind:"a"}});
const media = create();
media.kind.kind === "a" && media.a; // Property 'a' does not exist on type 'MyObject'.

🙁 Actual behavior

Compiler throws error on the last

Property 'a' does not exist on type 'MyObject'.
  Property 'a' does not exist on type '{ readonly kind: { kind: "b"; }; }'.

🙂 Expected behavior

By type definition, compiler has enough information to resolve that property a does exist on my object b/c there is no other option for media.kind.kind === "a"

[fatcerberus]

Duplicate of #18758

[typescript-bot]

This issue has been marked as a 'Duplicate' and has seen no recent activity. It has been automatically closed for house-keeping purposes.