more functional design principles

test/unit/shutdown.spec.js

@@ -2,20 +2,22 @@ import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest'
 import { registerCleanup, graceful, clearCleanup, initShutdownHandlers } from '../../server/utils/shutdown.js'
 
 describe('shutdown', () => {
-  let originalExit
-  let exitCalls
+  const testState = {
+    originalExit: null,
+    exitCalls: [],
+  }
 
   beforeEach(() => {
     clearCleanup()
-    exitCalls = []
-    originalExit = process.exit
+    testState.exitCalls = []
+    testState.originalExit = process.exit
     process.exit = vi.fn((code) => {
-      exitCalls.push(code)
+      testState.exitCalls.push(code)
     })
   })
 
   afterEach(() => {
-    process.exit = originalExit
+    process.exit = testState.originalExit
     clearCleanup()
   })
 
@@ -46,7 +48,7 @@ describe('shutdown', () => {
     await graceful()
 
     expect(calls).toEqual(['third', 'second', 'first'])
-    expect(exitCalls).toEqual([0])
+    expect(testState.exitCalls).toEqual([0])
   })
 
   it('handles cleanup function errors gracefully', async () => {
@@ -59,26 +61,26 @@ describe('shutdown', () => {
 
     await graceful()
 
-    expect(exitCalls).toEqual([0])
+    expect(testState.exitCalls).toEqual([0])
   })
 
   it('exits with code 1 on error', async () => {
     const error = new Error('Test error')
     await graceful(error)
 
-    expect(exitCalls).toEqual([1])
+    expect(testState.exitCalls).toEqual([1])
   })
 
   it('prevents multiple shutdowns', async () => {
-    let callCount = 0
+    const callCount = { value: 0 }
     registerCleanup(async () => {
-      callCount++
+      callCount.value++
     })
 
     await graceful()
     await graceful()
 
-    expect(callCount).toBe(1)
+    expect(callCount.value).toBe(1)
   })
 
   it('handles cleanup error during graceful shutdown', async () => {
@@ -88,7 +90,7 @@ describe('shutdown', () => {
 
     await graceful()
 
-    expect(exitCalls).toEqual([0])
+    expect(testState.exitCalls).toEqual([0])
   })
 
   it('handles error in executeCleanup catch block', async () => {
@@ -98,20 +100,20 @@ describe('shutdown', () => {
 
     await graceful()
 
-    expect(exitCalls.length).toBeGreaterThan(0)
+    expect(testState.exitCalls.length).toBeGreaterThan(0)
   })
 
   it('handles error with stack trace', async () => {
     const error = new Error('Test error')
     error.stack = 'Error: Test error\n    at test.js:1:1'
     await graceful(error)
-    expect(exitCalls).toEqual([1])
+    expect(testState.exitCalls).toEqual([1])
   })
 
   it('handles error without stack trace', async () => {
     const error = { message: 'Test error' }
     await graceful(error)
-    expect(exitCalls).toEqual([1])
+    expect(testState.exitCalls).toEqual([1])
   })
 
   it('handles timeout scenario', async () => {
@@ -119,7 +121,7 @@ describe('shutdown', () => {
       await new Promise(resolve => setTimeout(resolve, 40000))
     })
     const timeout = setTimeout(() => {
-      expect(exitCalls.length).toBeGreaterThan(0)
+      expect(testState.exitCalls.length).toBeGreaterThan(0)
     }, 35000)
     graceful()
     await new Promise(resolve => setTimeout(resolve, 100))
@@ -130,7 +132,7 @@ describe('shutdown', () => {
     registerCleanup(async () => {})
     await graceful()
     await graceful() // Second call should return early
-    expect(exitCalls.length).toBeGreaterThan(0)
+    expect(testState.exitCalls.length).toBeGreaterThan(0)
   })
 
   it('covers initShutdownHandlers', () => {
@@ -151,7 +153,7 @@ describe('shutdown', () => {
       throw new Error('Force error in cleanup')
     })
     await graceful()
-    expect(exitCalls.length).toBeGreaterThan(0)
+    expect(testState.exitCalls.length).toBeGreaterThan(0)
   })
 
   it('covers graceful catch block when executeCleanup throws', async () => {
@@ -176,7 +178,7 @@ describe('shutdown', () => {
     await graceful()
 
     // Should exit successfully (code 0) because executeCleanup handles errors internally
-    expect(exitCalls).toContain(0)
+    expect(testState.exitCalls).toContain(0)
     expect(clearTimeoutCalls.length).toBeGreaterThan(0)
     global.clearTimeout = originalClearTimeout
   })
@@ -213,7 +215,7 @@ describe('shutdown', () => {
     await new Promise(resolve => setTimeout(resolve, 10))
 
     expect(errorLogs.some(log => log.includes('Error in graceful shutdown'))).toBe(true)
-    expect(exitCalls).toContain(1)
+    expect(testState.exitCalls).toContain(1)
 
     process.on = originalOn
     process.exit = originalExit