fix some bug on extends find (go-xorm#916)

engine.go

@@ -1091,7 +1091,25 @@ func (engine *Engine) idOfV(rv reflect.Value) (core.PK, error) {
 	pk := make([]interface{}, len(table.PrimaryKeys))
 	for i, col := range table.PKColumns() {
 		var err error
-		pkField := v.FieldByName(col.FieldName)
+
+		fieldName := col.FieldName
+		for {
+			parts := strings.SplitN(fieldName, ".", 2)
+			if len(parts) == 1 {
+				break
+			}
+
+			v = v.FieldByName(parts[0])
+			if v.Kind() == reflect.Ptr {
+				v = v.Elem()
+			}
+			if v.Kind() != reflect.Struct {
+				return nil, ErrUnSupportedType
+			}
+			fieldName = parts[1]
+		}
+		fmt.Println(table.Name, fieldName, v)
+		pkField := v.FieldByName(fieldName)
 		switch pkField.Kind() {
 		case reflect.String:
 			pk[i], err = engine.idTypeAssertion(col, pkField.String())

session_find_test.go

@@ -655,5 +655,77 @@ func TestFindMapStringId(t *testing.T) {
 	cnt, err = testEngine.ID("1").Delete(new(FindMapDevice))
 	assert.NoError(t, err)
 	assert.EqualValues(t, 1, cnt)
+}
+
+func TestFindExtends(t *testing.T) {
+	type FindExtendsB struct {
+		ID int64
+	}
+
+	type FindExtendsA struct {
+		FindExtendsB `xorm:"extends"`
+	}
+
+	assert.NoError(t, prepareEngine())
+	assertSync(t, new(FindExtendsA))
+
+	cnt, err := testEngine.Insert(&FindExtendsA{
+		FindExtendsB: FindExtendsB{},
+	})
+	assert.NoError(t, err)
+	assert.EqualValues(t, 1, cnt)
+
+	cnt, err = testEngine.Insert(&FindExtendsA{
+		FindExtendsB: FindExtendsB{},
+	})
+	assert.NoError(t, err)
+	assert.EqualValues(t, 1, cnt)
+
+	var results []FindExtendsA
+	err = testEngine.Find(&results)
+	assert.NoError(t, err)
+	assert.EqualValues(t, 2, len(results))
+}
+
+func TestFindExtends3(t *testing.T) {
+	type FindExtendsCC struct {
+		ID   int64
+		Name string
+	}
+
+	type FindExtendsBB struct {
+		FindExtendsCC `xorm:"extends"`
+	}
+
+	type FindExtendsAA struct {
+		FindExtendsBB `xorm:"extends"`
+	}
 
+	assert.NoError(t, prepareEngine())
+	assertSync(t, new(FindExtendsAA))
+
+	cnt, err := testEngine.Insert(&FindExtendsAA{
+		FindExtendsBB: FindExtendsBB{
+			FindExtendsCC: FindExtendsCC{
+				Name: "cc1",
+			},
+		},
+	})
+	assert.NoError(t, err)
+	assert.EqualValues(t, 1, cnt)
+
+	cnt, err = testEngine.Insert(&FindExtendsAA{
+		FindExtendsBB: FindExtendsBB{
+			FindExtendsCC: FindExtendsCC{
+				Name: "cc2",
+			},
+		},
+	})
+	assert.NoError(t, err)
+	assert.EqualValues(t, 1, cnt)
+
+	var results []FindExtendsAA
+	err = testEngine.Find(&results)
+	assert.NoError(t, err)
+	assert.EqualValues(t, 2, len(results))
 }