feat: add makeURLSearchParams utility function (#7744)

packages/rest/__tests__/utils.test.ts

@@ -0,0 +1,60 @@
+import { makeURLSearchParams } from '../src';
+
+describe('makeURLSearchParams', () => {
+	test('GIVEN undefined THEN returns empty URLSearchParams', () => {
+		const params = makeURLSearchParams();
+
+		expect([...params.entries()]).toEqual([]);
+	});
+
+	test('GIVEN empty object THEN returns empty URLSearchParams', () => {
+		const params = makeURLSearchParams({});
+
+		expect([...params.entries()]).toEqual([]);
+	});
+
+	test('GIVEN a record of strings THEN returns URLSearchParams with strings', () => {
+		const params = makeURLSearchParams({ foo: 'bar', hello: 'world' });
+
+		expect([...params.entries()]).toEqual([
+			['foo', 'bar'],
+			['hello', 'world'],
+		]);
+	});
+
+	test('GIVEN a record of strings with nullish values THEN returns URLSearchParams without nullish values', () => {
+		const params = makeURLSearchParams({ foo: 'bar', hello: null, one: undefined });
+
+		expect([...params.entries()]).toEqual([['foo', 'bar']]);
+	});
+
+	test('GIVEN a record of non-string values THEN returns URLSearchParams with string values', () => {
+		const params = makeURLSearchParams({ life: 42, big: 100n, bool: true });
+
+		expect([...params.entries()]).toEqual([
+			['life', '42'],
+			['big', '100'],
+			['bool', 'true'],
+		]);
+	});
+
+	describe('objects', () => {
+		test('GIVEN a record of date values THEN URLSearchParams with ISO string values', () => {
+			const params = makeURLSearchParams({ before: new Date('2022-04-04T15:43:05.108Z'), after: new Date(NaN) });
+
+			expect([...params.entries()]).toEqual([['before', '2022-04-04T15:43:05.108Z']]);
+		});
+
+		test('GIVEN a record of plain object values THEN returns empty URLSearchParams', () => {
+			const params = makeURLSearchParams({ foo: {}, hello: { happy: true } });
+
+			expect([...params.entries()]).toEqual([]);
+		});
+
+		test('GIVEN a record of objects with overridden toString THEN returns non-empty URLSearchParams', () => {
+			const params = makeURLSearchParams({ foo: { toString: () => 'bar' } });
+
+			expect([...params.entries()]).toEqual([['foo', 'bar']]);
+		});
+	});
+});