From c6a22c50962028255a718f22fe7e8959e8c67884 Mon Sep 17 00:00:00 2001
From: Jinzhu <wosmvp@gmail.com>
Date: Wed, 16 Dec 2015 10:40:57 +0800
Subject: [PATCH] Refact fix invalid zero value for Preload

---
 preload.go | 30 +++++++++++-------------------
 1 file changed, 11 insertions(+), 19 deletions(-)

diff --git a/preload.go b/preload.go
index f3f9dabc..69efc01b 100644
--- a/preload.go
+++ b/preload.go
@@ -9,20 +9,18 @@ import (
 )
 
 func getRealValue(value reflect.Value, columns []string) (results []interface{}) {
-	for _, column := range columns {
-		pointedValue := reflect.Indirect(value)
-		// If v is a nil pointer, Indirect returns a zero Value!
-		// Therefor we need to check for a zero value,
-		// as FieldByName could panic
-		if !pointedValue.IsValid() {
-			continue
-		}
-		if pointedValue.FieldByName(column).IsValid() {
-			result := pointedValue.FieldByName(column).Interface()
-			if r, ok := result.(driver.Valuer); ok {
-				result, _ = r.Value()
+	// If value is a nil pointer, Indirect returns a zero Value!
+	// Therefor we need to check for a zero value,
+	// as FieldByName could panic
+	if pointedValue := reflect.Indirect(value); pointedValue.IsValid() {
+		for _, column := range columns {
+			if pointedValue.FieldByName(column).IsValid() {
+				result := pointedValue.FieldByName(column).Interface()
+				if r, ok := result.(driver.Valuer); ok {
+					result, _ = r.Value()
+				}
+				results = append(results, result)
 			}
-			results = append(results, result)
 		}
 	}
 	return
@@ -297,12 +295,6 @@ func (scope *Scope) handleManyToManyPreload(field *Field, conditions []interface
 			}
 		}
 	} else {
-		// If v is a nil pointer, Indirect returns a zero Value!
-		// Therefor we need to check for a zero value,
-		// as FieldByName could panic
-		if !scope.IndirectValue().IsValid() {
-			return
-		}
 		object := scope.IndirectValue()
 		source := getRealValue(object, associationForeignStructFieldNames)
 		field := object.FieldByName(field.Name)