Сan't create correct TypeScript types to apply the Partial utility to an intersection of a simple type and a generic

I want to understand how an intersection works when it’s necessary to use Partial. This is used for setStatePartialHook when the exact type for the state is unknown.

type ModorkParams = {
  clientSessionId: string;
};

type Config<T extends Record<string, string>> = ModorkParams & Omit<T,'clientSessionId'>;


const foo = <T extends Record<string, string> = {}>() => { 
  let t: Partial<Config<T>> = { clientSessionId: "fdfdf" }; // Type '{ clientSessionId: "fdfdf"; }' is not assignable to type 'Partial<Config<T>>'.(2322)
  console.log(t);
};

Why doesn't Partial take Omit into account?

type ModorkParams = {
  clientSessionId: string;
};

type Config<T extends {
  clientSessionId?: string;
}> = ModorkParams & T;

Give the same error.

You can't omit a literal type from its generic type, like you cannot do Exclude<string, 'clientSessionId'>, it would give string anyway, so your omitting Record<string,string> doesn't work but TS tries to do some work and infers T in the initialization as Omit<T, 'clientSessionId'> which is rejected due presence of clientSessionId in the object literal. Overall the whole construct seems overcomplicated given the absence of the whole life-cycle of t variable and redundant typing in the variable's initialization.

A simpler alternative would be

type ModorkParams = {
  clientSessionId: string;
};

type Config = ModorkParams & Record<string, string>;

const foo = () => { 
  let t: Config = { clientSessionId: 'asdf' };
  console.log(t);
};