Type alias circularly references itself

🔎 Search Terms

circular reference, generic, error TS2456, recursive

🕗 Version & Regression Information

• This is the behavior in every version I tried, and I reviewed the FAQ for entries about circular reference

⏯ Playground Link

https://www.typescriptlang.org/play/?ts=5.8.2#code/C4TwDgpgBAYg9nAKuaBeKBvAsAKClAMwQH4AuKAIwQBsIBDAOwG5cBfFnXUSKAIToDOEAKK0AthAbAAPIgB8UdPCQooAMky58AYwAWAS2oATAE6TyAYQCuA4HDGiIEqQG0Auh3zcI5RB3a4XKrWtvaOzsCKfIIi4pIyAOS6AIwJchxAA

💻 Code

type FooType = {
  foo?: boolean;
};

type BaseElement<T> = FooType & {
  children: CustomElement[];
  type: T;
};

type CustomElement = BaseElement<'h1'>;

🙁 Actual behavior

When defining a recursive type structure using a generic type, TypeScript incorrectly reports a Type alias 'CustomElement' circularly references itself.(2456) error, even though the type should be resolvable.
It gets weird when you move type: T; line above the children: CustomElement[]; and the error disappears. Also removing FooType will resolve the issue.

🙂 Expected behavior

In the first place the code should not throw any errors, in the second place the behavior should not change by reordering records of a type.

Additional information about the issue

No response

リンクされた TypeScript Playground の再現から始め、ジェネリックな交差型における 2 つのメンバー順序を比較します。再帰的な型エイリアスに対する循環参照の診断を追跡し、FooType を追加するとそれが変わる理由を特定します。完了条件は、有効な再帰構造で TS2456 が報告されなくなり、メンバー順序によって結果が変わらないことです。