rewrite using IoC and DI

model/media_test.go

@@ -0,0 +1,30 @@
+package model
+
+import (
+	"fmt"
+	"testing"
+)
+
+type A struct {
+	A string
+}
+
+type B struct {
+	B string
+}
+
+func TestStruct(t *testing.T) {
+	var x interface{} = &A{A: "123"}
+	y, ok := x.(*A)
+	fmt.Println(y, ok)
+	z, ok := x.(*B)
+	fmt.Println(z, ok)
+}
+
+func TestMedia_Copy(t *testing.T) {
+	m := &Media{Title: "asdf", User: &User{Name: "123"}}
+	m2 := m.Copy()
+	fmt.Println(m, m2)
+	m2.User.(*User).Name = "456"
+	fmt.Println(m.User.(*User).Name, m2)
+}