refactor: improve removeUndefinedKeys typing

Author: gao-sun

src/utilities/object.ts

@@ -8,6 +8,22 @@ export const isKeyInObject = <Key extends string>(
   // eslint-disable-next-line @typescript-eslint/ban-types
 ): object is object & Record<Key, unknown> => isObject(object) && key in object;
 
+/**
+ * A utility type that removes all keys with `undefined` values from an object.
+ *
+ * Note: Optional keys with `undefined` values are not removed.
+ *
+ * @example
+ * ```ts
+ * type Foo = { a: string; b: number | undefined; c?: boolean };
+ * type Bar = RemoveUndefinedKeys<Foo>;
+ * // Bar is { a: string; b: number; c?: boolean }
+ * ```
+ */
+type RemoveUndefinedKeys<T> = {
+  [Key in keyof T as T[Key] extends undefined ? never : Key]: Exclude<T[Key], undefined>;
+};
+
 /**
  * Remove all keys with `undefined` values from an object. This function only
  * performs a shallow removal, i.e. it does not remove `undefined` values nested
@@ -16,6 +32,9 @@ export const isKeyInObject = <Key extends string>(
  * @param object The object to remove `undefined` keys from.
  * @returns A new object with all `undefined` keys removed.
  */
-export const removeUndefinedKeys = <T extends Record<string, unknown>>(object: T): T =>
+// eslint-disable-next-line @typescript-eslint/ban-types -- this is a utility function
+export const removeUndefinedKeys = <T extends object>(object: T): RemoveUndefinedKeys<T> =>
   // eslint-disable-next-line no-restricted-syntax
-  Object.fromEntries(Object.entries(object).filter(([, value]) => value !== undefined)) as T;
+  Object.fromEntries(
+    Object.entries(object).filter(([, value]) => value !== undefined)
+  ) as RemoveUndefinedKeys<T>;