typescript helpers

helper.ts

export type UniqueArray<T> = T extends readonly [infer X, ...infer Rest]
	? InArray<Rest, X> extends true
		? ['Encountered value with duplicates:', X]
		: readonly [X, ...UniqueArray<Rest>] | readonly [...UniqueArray<Rest>]
	: T;

type InArray<T, X> = T extends readonly [X, ...infer _Rest]
	? true
	: T extends readonly [X]
	? true
	: T extends readonly [infer _, ...infer Rest]
	? InArray<Rest, X>
	: false;

export type RequireAtLeastOne<T, Keys extends keyof T = keyof T> = Pick<T, Exclude<keyof T, Keys>> &
	{
		[K in Keys]-?: Required<Pick<T, K>> & Partial<Pick<T, Exclude<Keys, K>>>;
	}[Keys];

type SnakeToCamelCase<S extends string> = S extends `${infer T}_${infer U}`
	? `${T}${Capitalize<SnakeToCamelCase<U>>}`
	: S;

export type SnakeToCamelCaseNested<T> = T extends object
	? {
			[K in keyof T as SnakeToCamelCase<K & string>]: SnakeToCamelCaseNested<T[K]>;
	  }
	: T;