solution: Project Euler Problem 28 (#1198)

Project-Euler/test/Problem028.test.js

@@ -0,0 +1,17 @@
+import { problem28 } from '../Problem028.js'
+
+describe('checking number spiral diagonals', () => {
+  it('should be invalid input if number is negative', () => {
+    expect(() => problem28(-3)).toThrowError('Dimension must be positive')
+  })
+  it('should be invalid input if number is not odd', () => {
+    expect(() => problem28(4)).toThrowError('Dimension must be odd')
+  })
+  test('if the number is equal to 5 result should be 101', () => {
+    expect(problem28(5)).toBe(101)
+  })
+  // Project Euler Condition Check
+  test('if the number is equal to 1001 result should be 669171001', () => {
+    expect(problem28(1001)).toBe(669171001)
+  })
+})