Add FillSliceWith helper function

contracts.go

@@ -0,0 +1,20 @@
+package kissorm
+
+import (
+	"context"
+)
+
+// ORMProvider describes the public behavior of this ORM
+type ORMProvider interface {
+	Find(ctx context.Context, item interface{}, query string, params ...interface{}) error
+	Insert(ctx context.Context, items ...interface{}) error
+	Delete(ctx context.Context, ids ...interface{}) error
+	Update(ctx context.Context, items ...interface{}) error
+	Query(ctx context.Context, query string, params ...interface{}) (Iterator, error)
+	QueryNext(ctx context.Context, rawIt Iterator, item interface{}) (done bool, err error)
+}
+
+// Iterator ...
+type Iterator interface {
+	Close() error
+}

kiss_orm.go

@@ -9,21 +9,6 @@ import (
 	"github.com/jinzhu/gorm"
 )
 
-// ORMProvider describes the public behavior of this ORM
-type ORMProvider interface {
-	Find(ctx context.Context, item interface{}, query string, params ...interface{}) error
-	Insert(ctx context.Context, items ...interface{}) error
-	Delete(ctx context.Context, ids ...interface{}) error
-	Update(ctx context.Context, items ...interface{}) error
-	Query(ctx context.Context, query string, params ...interface{}) (Iterator, error)
-	QueryNext(ctx context.Context, rawIt Iterator, item interface{}) (done bool, err error)
-}
-
-// Iterator ...
-type Iterator interface {
-	Close() error
-}
-
 // Client ...
 type Client struct {
 	tableName string
@@ -271,19 +256,19 @@ func getTagNames(t reflect.Type) structInfo {
 	return info
 }
 
-// UpdateStructWith is meant to be used on unit tests to mock
+// FillStructWith is meant to be used on unit tests to mock
 // the response from the database.
 //
 // The first argument is any struct you are passing to a kissorm func,
 // and the second is a map representing a database row you want
 // to use to update this struct.
-func UpdateStructWith(entity interface{}, dbRow map[string]interface{}) error {
+func FillStructWith(entity interface{}, dbRow map[string]interface{}) error {
 	v := reflect.ValueOf(entity)
 	t := v.Type()
 
 	if t.Kind() != reflect.Ptr {
 		return fmt.Errorf(
-			"UpdateStructWith: expected input to be a pointer to struct but got %T",
+			"FillStructWith: expected input to be a pointer to struct but got %T",
 			entity,
 		)
 	}
@@ -293,7 +278,7 @@ func UpdateStructWith(entity interface{}, dbRow map[string]interface{}) error {
 
 	if t.Kind() != reflect.Struct {
 		return fmt.Errorf(
-			"UpdateStructWith: expected input to be a kind of struct but got %T",
+			"FillStructWith: expected input kind to be a struct but got %T",
 			entity,
 		)
 	}
@@ -311,7 +296,7 @@ func UpdateStructWith(entity interface{}, dbRow map[string]interface{}) error {
 
 		if !attrValue.Type().ConvertibleTo(fieldType) {
 			return fmt.Errorf(
-				"UpdateStructWith: cannot convert atribute %s of type %v to type %T",
+				"FillStructWith: cannot convert atribute %s of type %v to type %T",
 				colName,
 				fieldType,
 				entity,
@@ -322,3 +307,71 @@ func UpdateStructWith(entity interface{}, dbRow map[string]interface{}) error {
 
 	return nil
 }
+
+// FillSliceWith is meant to be used on unit tests to mock
+// the response from the database.
+//
+// The first argument is any struct you are passing to a kissorm func,
+// and the second is a map representing a database row you want
+// to use to update this struct.
+func FillSliceWith(entities interface{}, dbRows []map[string]interface{}) error {
+	slicePtrValue := reflect.ValueOf(entities)
+	slicePtrType := slicePtrValue.Type()
+
+	if slicePtrType.Kind() != reflect.Ptr {
+		return fmt.Errorf(
+			"FillListWith: expected input to be a pointer to struct but got %T",
+			entities,
+		)
+	}
+
+	t := slicePtrType.Elem()
+	v := slicePtrValue.Elem()
+
+	if t.Kind() != reflect.Slice {
+		return fmt.Errorf(
+			"FillListWith: expected input kind to be a slice but got %T",
+			entities,
+		)
+	}
+
+	elemType := t.Elem()
+	isPtr := elemType.Kind() == reflect.Ptr
+
+	if isPtr {
+		elemType = elemType.Elem()
+	}
+
+	info, found := tagInfoCache[elemType]
+	if !found {
+		info = getTagNames(elemType)
+		tagInfoCache[elemType] = info
+	}
+
+	if elemType.Kind() != reflect.Struct {
+		return fmt.Errorf(
+			"FillListWith: expected input to be a slice of structs but got %T",
+			entities,
+		)
+	}
+
+	for idx, row := range dbRows {
+		if v.Len() <= idx {
+			var elemValue reflect.Value
+			elemValue = reflect.New(elemType)
+			if !isPtr {
+				elemValue = elemValue.Elem()
+			}
+			v = reflect.Append(v, elemValue)
+		}
+
+		err := FillStructWith(v.Index(idx).Addr().Interface(), row)
+		if err != nil {
+			return err
+		}
+	}
+
+	slicePtrValue.Elem().Set(v)
+
+	return nil
+}

kiss_orm_test.go

@@ -455,6 +455,29 @@ func TestIterator(t *testing.T) {
 	})
 }
 
+func TestFillSliceWith(t *testing.T) {
+	t.Run("should fill a list correctly", func(t *testing.T) {
+		var users []User
+		err := FillSliceWith(&users, []map[string]interface{}{
+			{
+				"name": "Jorge",
+			},
+			{
+				"name": "Luciana",
+			},
+			{
+				"name": "Breno",
+			},
+		})
+
+		assert.Equal(t, nil, err)
+		assert.Equal(t, 3, len(users))
+		assert.Equal(t, "Jorge", users[0].Name)
+		assert.Equal(t, "Luciana", users[1].Name)
+		assert.Equal(t, "Breno", users[2].Name)
+	})
+}
+
 func createTable() error {
 	db, err := gorm.Open("sqlite3", "/tmp/test.db")
 	if err != nil {