Nested generic calls don't inherit outer inferences when their return types are intersections containing functions

🔎 Search Terms

generic call inference intersection return type

🕗 Version & Regression Information

• This is the behavior in every version I tried

⏯ Playground Link

https://www.typescriptlang.org/play/?ts=5.6.0-dev.20240611#code/JYOwLgpgTgZghgYwgAgMIHsQ2AcwDwAqAfMgN4CwAUMsgppAB5gBcyBA3FTaAG7oDWEVhWo1kACgasCASlZ9gAE06iaEBhAStJ0mcgC8JBcq7IAvirNUqizQBs4UFDACuIBGGCZaTuJEJE4nRYuKwYIfjEcsjGKjb2js5uHl4gyAC2AJ4AkiB8ggBCUAIQIAHiwMLI6praUmx6hjHoSubRIjQ6DfItJpRmyABkyGCZAA4Q6DDIwHGUCL6Q4h209OosZKtuGwDM5gA0prwlrFm5+RBFJSDLpmoaWhIMjSQrYsgMd2IA9N-IAHoAfi+NAYADo6NswWB0AAxYAaRTiABMMhU7zMh1EZhkWJxc1sCAcTmQrncnm8ZzyJXKlU2NUeXVkBiMvTawlMTOisVMDLquhZzSUljmCwgfggt1EwUYG1IW3ArD2mKO1MEpxyaslb2qDzqLzIII+Rt+AOBqjE4Mh4GhcIRECRqPRYhV2NxVHxVCAA

💻 Code

interface Config<T> {
  context: T;
  invoke: {
    (x: T): void;
    exec: (x: T) => void;
  };
}

declare function create<T>(config: Config<T>): void;

declare function myInvokeBroken<T>(i: { exec: (x: T) => void }): {
  (x: T): void;
} & typeof i;

create({
  context: { count: 3 },
  invoke: myInvokeBroken({
    exec: (x) => {
      x
      // ^?
      x.count.toFixed(2);
    },
  }),
});

declare function myInvoke<T>(i: { exec: (x: T) => void }): {
  (x: T): void;
  exec: (x: T) => void;
};

create({
  context: { count: 3 },
  invoke: myInvoke({
    exec: (x) => {
      x
      // ^?
      x.count.toFixed(2);
    },
  }),
});

🙁 Actual behavior

x doesn't get contextually typed based on the outer inferences in the myInvokeBroken example

🙂 Expected behavior

I would expect myInvokeBroken and myInvoke to work here in the same way. Their return types are the same. It's only that myInvokeBroken is using an intersection in its return type while myInvoke isn't

Additional information about the issue

No response

リンクされた TypeScript Playground の再現コードから始め、2 つのジェネリック呼び出しに対する推論を比較します。特に、myInvokeBroken の intersection 戻り値型と、myInvoke の明示的な callable-object 戻り値型に注目してください。ネストされた exec callback にコンテキスト型を提供する type-checker の経路を追跡します。両方の例で x が { count: number } としてコンテキストに基づいて型付けされ、x.count.toFixed(2) が受け入れられ、その違いをカバーする回帰テストがあることが完了条件です。