test(hashx): add unsafe.Point test

pkg/structure/hashx/hashx_test.go

@@ -1,7 +1,10 @@
 package hashx
 
 import (
+	"fmt"
+	"reflect"
 	"testing"
+	"unsafe"
 
 	"github.com/stretchr/testify/require"
 )
@@ -60,3 +63,27 @@ func TestHashX_Add(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, s, "2")
 }
+
+func Test_Pointer(t *testing.T) {
+	s := make([]int, 9, 20)
+	lens := *(*int)(unsafe.Pointer(uintptr(unsafe.Pointer(&s)) + uintptr(8)))
+	fmt.Println(lens, len(s))
+
+	mp := make(map[string]int)
+	mp["qcrao"] = 100
+	mp["stefno"] = 18
+
+	count := **(**uint8)(unsafe.Pointer(uintptr(unsafe.Pointer(&mp)) + uintptr(16)))
+	fmt.Println(count, len(mp)) // 2
+}
+
+func string2bytes(s string) []byte {
+	stringHeader := (*reflect.StringHeader)(unsafe.Pointer(&s))
+
+	result := reflect.SliceHeader{
+		Data: stringHeader.Data,
+		Len:  stringHeader.Len,
+		Cap:  stringHeader.Len,
+	}
+	return *(*[]byte)(unsafe.Pointer(&result))
+}