From 3e4dbde920e3fe88a56a97429ab8146408d18da6 Mon Sep 17 00:00:00 2001
From: Jinzhu <wosmvp@gmail.com>
Date: Tue, 30 Jun 2020 22:47:21 +0800
Subject: [PATCH] Test Hooks For Slice

---
 callbacks/callmethod.go |  4 +++-
 statement.go            | 17 +++++++++++----
 tests/hooks_test.go     | 48 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 64 insertions(+), 5 deletions(-)

diff --git a/callbacks/callmethod.go b/callbacks/callmethod.go
index a0e9b0e7..0160f354 100644
--- a/callbacks/callmethod.go
+++ b/callbacks/callmethod.go
@@ -11,8 +11,10 @@ func callMethod(db *gorm.DB, fc func(value interface{}, tx *gorm.DB) bool) {
 	if called := fc(db.Statement.Dest, tx); !called {
 		switch db.Statement.ReflectValue.Kind() {
 		case reflect.Slice, reflect.Array:
+			db.Statement.CurDestIndex = 0
 			for i := 0; i < db.Statement.ReflectValue.Len(); i++ {
-				fc(db.Statement.ReflectValue.Index(i).Addr().Interface(), tx)
+				fc(reflect.Indirect(db.Statement.ReflectValue.Index(i)).Addr().Interface(), tx)
+				db.Statement.CurDestIndex++
 			}
 		case reflect.Struct:
 			fc(db.Statement.ReflectValue.Addr().Interface(), tx)
diff --git a/statement.go b/statement.go
index 164ddbd7..e65a064f 100644
--- a/statement.go
+++ b/statement.go
@@ -38,6 +38,7 @@ type Statement struct {
 	SQL                  strings.Builder
 	Vars                 []interface{}
 	NamedVars            []sql.NamedArg
+	CurDestIndex         int
 	attrs                []interface{}
 	assigns              []interface{}
 }
@@ -379,7 +380,12 @@ func (stmt *Statement) SetColumn(name string, value interface{}) {
 		v[name] = value
 	} else if stmt.Schema != nil {
 		if field := stmt.Schema.LookUpField(name); field != nil {
-			field.Set(stmt.ReflectValue, value)
+			switch stmt.ReflectValue.Kind() {
+			case reflect.Slice, reflect.Array:
+				field.Set(stmt.ReflectValue.Index(stmt.CurDestIndex), value)
+			case reflect.Struct:
+				field.Set(stmt.ReflectValue, value)
+			}
 		} else {
 			stmt.AddError(ErrInvalidField)
 		}
@@ -395,17 +401,20 @@ func (stmt *Statement) Changed(fields ...string) bool {
 		modelValue = modelValue.Elem()
 	}
 
+	switch modelValue.Kind() {
+	case reflect.Slice, reflect.Array:
+		modelValue = stmt.ReflectValue.Index(stmt.CurDestIndex)
+	}
+
 	selectColumns, restricted := stmt.SelectAndOmitColumns(false, true)
 	changed := func(field *schema.Field) bool {
-		fieldValue, isZero := field.ValueOf(modelValue)
+		fieldValue, _ := field.ValueOf(modelValue)
 		if v, ok := selectColumns[field.DBName]; (ok && v) || (!ok && !restricted) {
 			if v, ok := stmt.Dest.(map[string]interface{}); ok {
 				if fv, ok := v[field.Name]; ok {
 					return !utils.AssertEqual(fv, fieldValue)
 				} else if fv, ok := v[field.DBName]; ok {
 					return !utils.AssertEqual(fv, fieldValue)
-				} else if isZero {
-					return true
 				}
 			} else {
 				changedValue, _ := field.ValueOf(stmt.ReflectValue)
diff --git a/tests/hooks_test.go b/tests/hooks_test.go
index 8f8c60f5..ed5ee746 100644
--- a/tests/hooks_test.go
+++ b/tests/hooks_test.go
@@ -366,3 +366,51 @@ func TestSetColumn(t *testing.T) {
 
 	AssertEqual(t, result2, product)
 }
+
+func TestHooksForSlice(t *testing.T) {
+	products := []*Product3{
+		{Name: "Product-1", Price: 100},
+		{Name: "Product-2", Price: 200},
+		{Name: "Product-3", Price: 300},
+	}
+
+	DB.Create(&products)
+
+	for idx, value := range []int64{200, 300, 400} {
+		if products[idx].Price != value {
+			t.Errorf("invalid price for product #%v, expects: %v, got %v", idx, value, products[idx].Price)
+		}
+	}
+
+	DB.Model(&products).Update("Name", "product-name")
+
+	// will set all product's price to last product's price + 10
+	for idx, value := range []int64{410, 410, 410} {
+		if products[idx].Price != value {
+			t.Errorf("invalid price for product #%v, expects: %v, got %v", idx, value, products[idx].Price)
+		}
+	}
+
+	products2 := []Product3{
+		{Name: "Product-1", Price: 100},
+		{Name: "Product-2", Price: 200},
+		{Name: "Product-3", Price: 300},
+	}
+
+	DB.Create(&products2)
+
+	for idx, value := range []int64{200, 300, 400} {
+		if products2[idx].Price != value {
+			t.Errorf("invalid price for product #%v, expects: %v, got %v", idx, value, products2[idx].Price)
+		}
+	}
+
+	DB.Model(&products2).Update("Name", "product-name")
+
+	// will set all product's price to last product's price + 10
+	for idx, value := range []int64{410, 410, 410} {
+		if products2[idx].Price != value {
+			t.Errorf("invalid price for product #%v, expects: %v, got %v", idx, value, products2[idx].Price)
+		}
+	}
+}