Fix skip after scan callback for nil values

main.go

@@ -177,15 +177,6 @@ func (s *DB) QueryExpr() *expr {
 	return Expr(scope.SQL, scope.SQLVars...)
 }
 
-// SubQuery returns the query as sub query
-func (s *DB) SubQuery() *expr {
-	scope := s.NewScope(s.Value)
-	scope.InstanceSet("skip_bindvar", true)
-	scope.prepareQuerySQL()
-
-	return Expr(fmt.Sprintf("(%v)", scope.SQL), scope.SQLVars...)
-}
-
 // Where return a new relation, filter records with given conditions, accepts `map`, `struct` or `string` as conditions, refer http://jinzhu.github.io/gorm/crud.html#query
 func (s *DB) Where(query interface{}, args ...interface{}) *DB {
 	return s.clone().search.Where(query, args...).db
@@ -820,16 +811,17 @@ func (s *DB) EnableAfterScanCallback(typs ...interface{}) *DB  {
 func (s *DB) EnabledAfterScanCallback(typs ...interface{}) (ok bool) {
 	key := "gorm:disable_after_scan"
 
-	if v, ok := s.values[key]; !ok || v.(bool) {
-		for _, typ := range typs {
-			rType := indirectType(reflect.TypeOf(typ))
-			v, ok = s.values[key + ":" + rType.PkgPath() + "." + rType.Name()]
-			if ok && !v.(bool) {
-				return false
-			}
-		}
-		return true
+	if v, ok := s.values[key]; ok {
+		return !v.(bool)
 	}
 
-	return false
+	for _, typ := range typs {
+		rType := indirectType(reflect.TypeOf(typ))
+		v, ok := s.values[key + ":" + rType.PkgPath() + "." + rType.Name()]
+		if ok && v.(bool) {
+			return false
+		}
+	}
+
+	return true
 }

scope.go

@@ -475,16 +475,18 @@ func (scope *Scope) quoteIfPossible(str string) string {
 
 // call after field method callbacks
 func (scope *Scope) afterScanCallback(scannerFields map[int]*Field, disableScanField map[int]bool) {
-	if !scope.HasError() {
+	if !scope.HasError() && scope.Value != nil {
 		if scope.DB().EnabledAfterScanCallback(scope.Value) {
 			scopeValue := reflect.ValueOf(scope)
 			for index, field := range scannerFields {
-				// if calbacks enabled for field type
+				// if not is nill and if calbacks enabled for field type
 				if StructFieldMethodCallbacks.EnabledFieldType(field.Field.Type()) {
 					// not disabled on scan
 					if _, ok := disableScanField[index]; !ok {
-						reflectValue := field.Field.Addr()
-						field.CallMethodCallback("AfterScan", reflectValue, scopeValue)
+						if !isNil(field.Field) {
+							reflectValue := field.Field.Addr()
+							field.CallMethodCallback("AfterScan", reflectValue, scopeValue)
+						}
 					}
 				}
 			}

scope_test.go

@@ -127,20 +127,16 @@ func TestAfterFieldScanDisableCallback(t *testing.T) {
 		DB := DB.DisableAfterScanCallback(typs...)
 		var model2 WithFieldAfterScanCallback
 		if err := DB.Where("id = ?", model.ID).First(&model2).Error; err != nil {
-			t.Errorf("%q: No error should happen when querying WithFieldAfterScanCallback with valuer, but got %v", len(typs), err)
+			t.Errorf("%v: No error should happen when querying WithFieldAfterScanCallback with valuer, but got %v", len(typs), err)
 		}
 
-		dotest := func(i int, value string, field AfterScanFieldInterface) {
+		dotest := func(i int, field AfterScanFieldInterface) {
 			if !field.CalledFieldIsNill() {
-				t.Errorf("%q: Expected Name%v.calledField is not nil", len(typs), i)
-			}
-
-			if !field.CalledScopeIsNill() {
-				t.Errorf("%q: Expected Name%v.calledScope is not nil", len(typs), i)
+				t.Errorf("%v: Expected Name%v.calledField is nil", len(typs), i)
 			}
 		}
 
-		dotest(1, model.Name1.data, model2.Name1)
+		dotest(1, model2.Name1)
 	}
 
 	run()

utils.go

@@ -367,4 +367,15 @@ func checkOrPanic(err error) {
 	if err != nil {
 		panic(err)
 	}
+}
+
+// check if value is nil
+func isNil(value reflect.Value) bool {
+	if value.Kind() != reflect.Ptr {
+		return false
+	}
+	if value.Pointer() == 0 {
+		return true
+	}
+	return false
 }