omit

1/**
2 * Returns a new object without the specified keys.
3 *
4 * @param obj - The source object.
5 * @param keys - An array of keys to omit from the object.
6 * @returns A new object without the omitted keys.
7 */
8export function omit<T extends object, K extends keyof T>(obj: T, keys: K[]): Omit<T, K> {
9  const result = {} as Omit<T, K>;
10  for (const key in obj) {
11    if (!keys.includes(key as K)) {
12      result[key as Exclude<keyof T, K>] = obj[key];
13    }
14  }
15  return result;
16}

1test('omit - removes specified keys from object', () => {
2  const obj = { a: 1, b: 2, c: 3 };
3  expect(omit(obj, ['b'])).toEqual({ a: 1, c: 3 });
4});
5
6test('omit - removes multiple keys', () => {
7  const obj = { a: 1, b: 2, c: 3 };
8  expect(omit(obj, ['a', 'c'])).toEqual({ b: 2 });
9});
10
11test('omit - returns original object if no keys match', () => {
12  const obj = { a: 1, b: 2 };
13  expect(omit(obj, ['x' as any, 'y' as any])).toEqual(obj);
14});
15
16test('omit - returns empty object if all keys removed', () => {
17  const obj = { a: 1 };
18  expect(omit(obj, ['a'])).toEqual({});
19});
20
21test('omit - works with empty object', () => {
22  expect(omit({}, ['a'])).toEqual({});
23});
24
25test('omit - works with empty keys array', () => {
26  const obj = { a: 1, b: 2 };
27  expect(omit(obj, [])).toEqual({ a: 1, b: 2 });
28});