feat(utilities): add objectEntries function (#471)

* feat(utilities): add `objectEntries` function

* test(objectEntries): cover readonly types

* fix(objectEntires): return type

Co-authored-by: imranbarbhuiya

* fix(objectEntries): return type for arrays

* Update packages/utilities/src/lib/objectEntries.ts

Co-authored-by: Jeroen Claassens <jeroen.claassens@live.nl>

packages/utilities/src/index.ts

@@ -32,6 +32,7 @@ export * from './lib/makeObject';
 export * from './lib/mergeDefault';
 export * from './lib/mergeObjects';
 export * from './lib/noop';
+export * from './lib/objectEntries';
 export * from './lib/objectToTuples';
 export * from './lib/objectValues';
 export * from './lib/parseUrl';

packages/utilities/src/lib/objectEntries.ts

@@ -0,0 +1,5 @@
+import type { NonNullObject } from './utilityTypes';
+
+export function objectEntries<T extends NonNullObject>(obj: T): T extends ArrayLike<any> ? [`${number}`, T[number]][] : [keyof T, T[keyof T]][] {
+	return Object.entries(obj) as T extends ArrayLike<infer Values> ? Values[] : [keyof T, T[keyof T]][];
+}

packages/utilities/tests/objectEntries.test.ts

@@ -0,0 +1,45 @@
+import { objectEntries } from '../src';
+
+describe('objectEntries', () => {
+	test('GIVEN basic readonly THEN returns expected', () => {
+		const source = { a: 'Hello', b: 420 } as const;
+		const expected = [
+			['a', 'Hello'],
+			['b', 420]
+		] as [string, unknown][];
+
+		expect<['a' | 'b', 'Hello' | 420][]>(objectEntries(source)).toEqual(expected);
+	});
+
+	test('GIVEN deep readonly THEN returns expected', () => {
+		const source = { a: 'Hello', b: 420, deep: { i: [] } } as const;
+		const expected = [
+			['a', 'Hello'],
+			['b', 420],
+			['deep', { i: [] }]
+		] as [string, unknown][];
+
+		expect<['a' | 'b' | 'deep', 'Hello' | 420 | { i: readonly [] }][]>(objectEntries(source)).toEqual(expected);
+	});
+
+	test('GIVEN basic THEN returns expected', () => {
+		const source = { a: 'Hello', b: 420 };
+		const expected = [
+			['a', 'Hello'],
+			['b', 420]
+		] as [string, unknown][];
+
+		expect(objectEntries(source)).toEqual(expected);
+	});
+
+	test('GIVEN deep THEN returns expected', () => {
+		const source = { a: 'Hello', b: 420, deep: { i: [] } };
+		const expected = [
+			['a', 'Hello'],
+			['b', 420],
+			['deep', { i: [] }]
+		] as [string, unknown][];
+
+		expect(objectEntries(source)).toEqual(expected);
+	});
+});