Generated spec does not match type passed to @Body

[rosslavery]

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Expected Behavior

Consider a utility type and example model as follows:

// Reusable utility type
type RepositoryFilterOptions<T> = {
  [P in keyof T]?: T[P] extends string | number ? T[P] | T[P][] : T[P];
};

// Example model
interface ListUser {
  id: string;
  age: number;
  active: boolean;
}

The TS compiler in editor properly understands the computed type as:

type ExampleListUser = RepositoryFilterOptions<ListUser>;

// Resulting type computation:
{
  id?: string | string[];
  age?: number | number[];
  active?: boolean;
}

Current Behavior

Currently, tsoa is understanding this type as if the T[P] extends string | number ? T[P] | T[P][] : T[P]; part of the utility type isn't there. It just infers the original type and uses that instead.

type ExampleListUser = RepositoryFilterOptions<ListUser>;

// Simulation of tsoa type computation:
{
  id: string;
  age: number;
  active: boolean;
}

Example spec output (incorrect based on above):

Version of the library: 4.1.3 Version of NodeJS: 16 LTS

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