From 23a143717cf1e19f35fa5f2d014b9ed821182aa0 Mon Sep 17 00:00:00 2001
From: Lunny Xiao <xiaolunwen@gmail.com>
Date: Wed, 16 Jun 2021 11:15:13 +0800
Subject: [PATCH] detect the scan type according type

---
 convert.go        |  4 +++-
 schemas/column.go |  5 +++--
 session.go        | 11 +++++------
 session_get.go    | 32 ++++++++++++++++++++++++++------
 tags/parser.go    |  1 -
 5 files changed, 37 insertions(+), 16 deletions(-)

diff --git a/convert.go b/convert.go
index 081e799f..81c52f86 100644
--- a/convert.go
+++ b/convert.go
@@ -611,8 +611,10 @@ func asKind(vv reflect.Value, tp reflect.Type) (interface{}, error) {
 			}
 			return v, nil
 		}
+	default:
+		return vv.Interface(), nil
 	}
-	return nil, fmt.Errorf("unsupported primary key type: %v, %v", tp, vv)
+	return nil, fmt.Errorf("asKind unsupported  type: %v, %v", tp, vv)
 }
 
 func asBool(bs []byte) (bool, error) {
diff --git a/schemas/column.go b/schemas/column.go
index 4bbb6c2d..78a28cfd 100644
--- a/schemas/column.go
+++ b/schemas/column.go
@@ -22,8 +22,9 @@ const (
 type Column struct {
 	Name            string
 	TableName       string
-	FieldName       string // Available only when parsed from a struct
-	FieldIndex      []int  // Available only when parsed from a struct
+	FieldName       string       // Available only when parsed from a struct
+	FieldIndex      []int        // Available only when parsed from a struct
+	Type            reflect.Type // Available only when parsed from a struct
 	SQLType         SQLType
 	IsJSON          bool
 	Length          int
diff --git a/session.go b/session.go
index 8a645815..6b309659 100644
--- a/session.go
+++ b/session.go
@@ -449,11 +449,6 @@ func (session *Session) row2Slice(rows *core.Rows, types []*sql.ColumnType, fiel
 	return scanResults, nil
 }
 
-var (
-	scannerTypePlaceHolder sql.Scanner
-	scannerType            = reflect.TypeOf(&scannerTypePlaceHolder).Elem()
-)
-
 // convertAssign converts an interface src to dst reflect.Value fieldValue
 func (session *Session) convertAssign(fieldValue *reflect.Value, columnName string, src interface{}, table *schemas.Table, pk *schemas.PK, idx int) error {
 	if fieldValue == nil {
@@ -469,6 +464,10 @@ func (session *Session) convertAssign(fieldValue *reflect.Value, columnName stri
 		return nil
 	}
 
+	if fieldValue.Kind() == reflect.Ptr && fieldValue.IsNil() {
+		fieldValue.Set(reflect.New(fieldValue.Type().Elem()))
+	}
+
 	fmt.Printf("----- %v <------ %v \n", fieldValue.Type(), rawValue.Type())
 	if fieldValue.Type() == rawValue.Type() {
 		fieldValue.Set(rawValue)
@@ -518,7 +517,7 @@ func (session *Session) convertAssign(fieldValue *reflect.Value, columnName stri
 		case *sql.NullString:
 			if t.Valid {
 				if fieldValue.IsNil() {
-					fieldValue.Set(reflect.New(fieldValue.Type().Elem()))
+					//fieldValue.Set(reflect.New(fieldValue.Type().Elem()))
 					structConvert = fieldValue.Interface().(convert.Conversion)
 				}
 				if err := structConvert.FromDB([]byte(t.String)); err != nil {
diff --git a/session_get.go b/session_get.go
index bb848c06..d8836274 100644
--- a/session_get.go
+++ b/session_get.go
@@ -298,16 +298,36 @@ func (session *Session) getVars(rows *core.Rows, types []*sql.ColumnType, fields
 }
 
 func (session *Session) getStruct(rows *core.Rows, types []*sql.ColumnType, fields []string, table *schemas.Table, bean interface{}) (bool, error) {
-	fields, err := rows.Columns()
+	var scanResults = make([]interface{}, 0, len(types))
+	for i, tp := range types {
+		col := table.GetColumn(fields[i])
+		if col == nil {
+			return true, fmt.Errorf("cannot find column named %v from columns %v", fields[i], table.ColumnsSeq())
+		}
+		if col.Type.Implements(scannerType) {
+			scanResults = append(scanResults, &sql.RawBytes{})
+		} else if col.Type.Implements(conversionType) {
+			scanResults = append(scanResults, &sql.RawBytes{})
+		} else {
+			v, err := session.engine.driver.GenScanResult(tp.DatabaseTypeName())
+			if err != nil {
+				return true, err
+			}
+			scanResults = append(scanResults, v)
+		}
+	}
+
+	for _, closure := range session.beforeClosures {
+		closure(bean)
+	}
+
+	err := session.engine.scan(rows, types, scanResults...)
 	if err != nil {
-		// WARN: Alougth rows return true, but get fields failed
 		return true, err
 	}
 
-	scanResults, err := session.row2Slice(rows, fields, bean)
-	if err != nil {
-		return false, err
-	}
+	executeBeforeSet(bean, fields, scanResults)
+
 	// close it before convert data
 	rows.Close()
 
diff --git a/tags/parser.go b/tags/parser.go
index fc624d9f..b793a8f1 100644
--- a/tags/parser.go
+++ b/tags/parser.go
@@ -271,7 +271,6 @@ func (parser *Parser) Parse(v reflect.Value) (*schemas.Table, error) {
 	if t.Kind() == reflect.Ptr {
 		t = t.Elem()
 		v = v.Elem()
-		fmt.Println("======3333", v)
 	}
 	if t.Kind() != reflect.Struct {
 		return nil, ErrUnsupportedType