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

Comienza con la reproducción enlazada en TypeScript Playground y compara la inferencia de las dos llamadas genéricas, centrándote en el tipo de retorno de intersección de myInvokeBroken frente al tipo de retorno explícito de objeto invocable de myInvoke. Traza el recorrido del comprobador de tipos que proporciona tipos contextuales al callback exec anidado. Se considera terminado cuando ambos ejemplos tipan contextualmente x como { count: number } y se acepta x.count.toFixed(2), con una prueba de regresión que cubra la diferencia.