isFloat

1/**
2 * Checks if a number is a floating-point number (i.e. not an integer).
3 *
4 * @param num - The number to check.
5 * @returns True if the number is a float, false if it's an integer or invalid.
6 */
7export function isFloat(num: number): boolean {
8  return Number.isFinite(num) && Math.floor(num) !== num;
9}

1test('isFloat - float number', () => {
2  expect(isFloat(3.14)).toBe(true);
3});
4
5test('isFloat - integer number', () => {
6  expect(isFloat(5)).toBe(false);
7});
8
9test('isFloat - negative float', () => {
10  expect(isFloat(-2.718)).toBe(true);
11});
12
13test('isFloat - negative integer', () => {
14  expect(isFloat(-4)).toBe(false);
15});
16
17test('isFloat - zero', () => {
18  expect(isFloat(0)).toBe(false);
19});
20
21test('isFloat - NaN', () => {
22  expect(isFloat(NaN)).toBe(false);
23});
24
25test('isFloat - Infinity', () => {
26  expect(isFloat(Infinity)).toBe(false);
27});
28
29test('isFloat - very small float', () => {
30  expect(isFloat(1e-8)).toBe(true);
31});