Function TestPanicDo

pkg/singleflight/singleflight_test.go:220–255

Test singleflight behaves correctly after Do panic. See https://github.com/golang/go/issues/41133

(t *testing.T)

// Test singleflight behaves correctly after Do panic.
// See https://github.com/golang/go/issues/41133
func TestPanicDo(t *testing.T) {
	var g Group[string, any]
	fn := func() (any, error) {
		panic("invalid memory address or nil pointer dereference")
	}

	const n = 5
	waited := int32(n)
	panicCount := int32(0)
	done := make(chan struct{})
	for i := 0; i < n; i++ {
		go func() {
			defer func() {
				if err := recover(); err != nil {
					t.Logf("Got panic: %v\n%s", err, debug.Stack())
					atomic.AddInt32(&panicCount, 1)
				}

				if atomic.AddInt32(&waited, -1) == 0 {
					close(done)
				}
			}()

			g.Do("key", fn)
		}()
	}

	select {
	case <-done:
		if panicCount != n {
			t.Errorf("Expect %d panic, but got %d", n, panicCount)
		}
	case <-time.After(time.Second):
		t.Fatalf("Do hangs")
	}
}

func TestGoexitDo(t *testing.T) {
	var g Group[string, any]