Multiple exercises were added to the TypeScript track in this commit.

typescript/collatz-conjecture/collatz-conjecture.test.ts

@@ -0,0 +1,45 @@
+import { describe, it, expect, xit } from '@jest/globals'
+import { steps } from './collatz-conjecture.ts'
+
+describe('CollatzConjecture', () => {
+  it('zero steps for one', () => {
+    const expected = 0
+    expect(steps(1)).toBe(expected)
+  })
+
+  it('divide if even', () => {
+    const expected = 4
+    expect(steps(16)).toBe(expected)
+  })
+
+  it('even and odd steps', () => {
+    const expected = 9
+    expect(steps(12)).toBe(expected)
+  })
+
+  it('Large number of even and odd steps', () => {
+    const expected = 152
+    expect(steps(1000000)).toBe(expected)
+  })
+
+  it('zero is an error', () => {
+    const expected = 'Only positive integers are allowed'
+    expect(() => {
+      steps(0)
+    }).toThrow(expected)
+  })
+
+  it('negative value is an error', () => {
+    const expected = 'Only positive integers are allowed'
+    expect(() => {
+      steps(-15)
+    }).toThrow(expected)
+  })
+
+  it('non-integer value is an error', () => {
+    const expected = 'Only positive integers are allowed'
+    expect(() => {
+      steps(3.1415)
+    }).toThrow(expected)
+  })
+})