[Tests] Add unit tests for hrtime utilities

packages/cli-kit/src/public/node/hrtime.test.ts

@@ -0,0 +1,47 @@
+import {startHRTime, endHRTimeInMs} from './hrtime.js'
+import {describe, test, expect, vi} from 'vitest'
+
+describe('hrtime', () => {
+  test('startHRTime returns the current high-resolution real time', () => {
+    // Given
+    const mockTime: [number, number] = [123, 456]
+    vi.spyOn(process, 'hrtime').mockReturnValue(mockTime)
+
+    // When
+    const result = startHRTime()
+
+    // Then
+    expect(process.hrtime).toHaveBeenCalled()
+    expect(result).toEqual(mockTime)
+  })
+
+  test('endHRTimeInMs returns the time in milliseconds with 2 decimal places', () => {
+    // Given
+    const startTime: [number, number] = [100, 0]
+    const diffTime: [number, number] = [1, 500000]
+    vi.spyOn(process, 'hrtime').mockReturnValue(diffTime)
+
+    // When
+    const result = endHRTimeInMs(startTime)
+
+    // Then
+    expect(process.hrtime).toHaveBeenCalledWith(startTime)
+    // 1 second + 500,000 nanoseconds = 1000ms + 0.5ms = 1000.5ms
+    expect(result).toBe('1000.50')
+  })
+
+  test('endHRTimeInMs handles sub-millisecond precision', () => {
+    // Given
+    const startTime: [number, number] = [100, 0]
+    const diffTime: [number, number] = [0, 1234567]
+    vi.spyOn(process, 'hrtime').mockReturnValue(diffTime)
+
+    // When
+    const result = endHRTimeInMs(startTime)
+
+    // Then
+    expect(process.hrtime).toHaveBeenCalledWith(startTime)
+    // 0 seconds + 1,234,567 nanoseconds = 1.234567ms
+    expect(result).toBe('1.23')
+  })
+})