Fix: FindInBatches ignores errors (#4203)

finisher_api.go

@@ -190,6 +190,8 @@ func (db *DB) FindInBatches(dest interface{}, batchSize int, fc func(tx *DB, bat
 
 		if result.Error == nil && result.RowsAffected != 0 {
 			tx.AddError(fc(result, batch))
+		} else if result.Error != nil {
+			tx.AddError(result.Error)
 		}
 
 		if tx.Error != nil || int(result.RowsAffected) < batchSize {

tests/query_test.go

@@ -292,6 +292,34 @@ func TestFindInBatches(t *testing.T) {
 	}
 }
 
+func TestFindInBatchesWithError(t *testing.T) {
+	var users = []User{
+		*GetUser("find_in_batches_with_error", Config{}),
+		*GetUser("find_in_batches_with_error", Config{}),
+		*GetUser("find_in_batches_with_error", Config{}),
+		*GetUser("find_in_batches_with_error", Config{}),
+		*GetUser("find_in_batches_with_error", Config{}),
+		*GetUser("find_in_batches_with_error", Config{}),
+	}
+
+	DB.Create(&users)
+
+	var (
+		results    []User
+		totalBatch int
+	)
+
+	if result := DB.Table("wrong_table").Where("name = ?", users[0].Name).FindInBatches(&results, 2, func(tx *gorm.DB, batch int) error {
+		totalBatch += batch
+		return nil
+	}); result.Error == nil || result.RowsAffected > 0 {
+		t.Fatal("expected errors to have occurred, but nothing happened")
+	}
+	if totalBatch != 0 {
+		t.Fatalf("incorrect total batch, expected: %v, got: %v", 0, totalBatch)
+	}
+}
+
 func TestFillSmallerStruct(t *testing.T) {
 	user := User{Name: "SmallerUser", Age: 100}
 	DB.Save(&user)