[Bug] Race condition on spinner.Suffix field in UpdateSpinnerMessage

[e-gineer]

Severity: HIGH

Bug Summary

The spinner.Suffix field is modified concurrently without synchronization when UpdateSpinnerMessage() is called from multiple goroutines, causing data races.

Location

• File: pkg/statushooks/spinner.go
• Function: UpdateSpinnerMessage() (line 111)
• Line: 113 - s.spinner.Suffix = fmt.Sprintf(" %s", newMessage)

Reproduction

func TestSpinnerConcurrentUpdate(t *testing.T) {
    spinner := NewStatusSpinnerHook()
    spinner.Show()
    defer spinner.Hide()

    var wg sync.WaitGroup
    for i := 0; i < 100; i++ {
        wg.Add(1)
        go func(n int) {
            defer wg.Done()
            spinner.UpdateSpinnerMessage(fmt.Sprintf("msg-%d", n))
        }(i)
    }
    wg.Wait()
}

Run with: go test -race ./pkg/statushooks/...

Evidence

Race detector shows:

• Write at spinner.Suffix in UpdateSpinnerMessage (line 113)
• Concurrent reads/writes from multiple goroutines
• Also races with Show() which reads spinner.Suffix (line 104)

Impact

• When: Multiple goroutines update status messages concurrently (common in parallel operations)
• Effect:
  • Corrupted spinner messages
  • Potential string corruption leading to garbled output
  • Data race failures in tests
  • Undefined behavior

Proposed Fix

Add mutex protection for spinner.Suffix modifications:

type StatusSpinner struct {
    spinner *spinner.Spinner
    cancel  chan struct{}
    delay   time.Duration
    visible bool
    mu      sync.RWMutex  // Add mutex
}

func (s *StatusSpinner) UpdateSpinnerMessage(newMessage string) {
    newMessage = s.truncateSpinnerMessageToScreen(newMessage)
    
    s.mu.Lock()
    s.spinner.Suffix = fmt.Sprintf(" %s", newMessage)
    visible := s.visible
    active := s.spinner.Active()
    s.mu.Unlock()
    
    if visible && !active {
        s.spinner.Start()
    }
}

---

Found by: Wave 3 Task 1 (Statushooks)
Test: TestSpinnerConcurrentUpdate in pkg/statushooks/statushooks_test.go