Add struct ptr (#11)

guonaihong · web-flow · commit 49eb0d1866b2 · 2023-02-22T11:14:38.000+08:00
* dst有指针类型结构体

* fix
diff --git a/.gitignore b/.gitignore
@@ -1,4 +1,5 @@
 # Binaries for programs and plugins
+/cover.cov
 *swp
 *~
 *.exe
diff --git a/deepcopy.go b/deepcopy.go
@@ -201,9 +201,22 @@ func (d *deepCopy) checkCycle(sField reflect.Value) error {
 func (d *deepCopy) cpyStruct(dst, src reflect.Value, depth int) error {
 
 	if dst.Kind() != src.Kind() {
-		if dst.Kind() == reflect.Ptr && !dst.IsNil() {
-			dst = dst.Elem()
-			return d.cpyStruct(dst, src, depth)
+		if dst.Kind() == reflect.Ptr {
+			// 不是空指针，直接解引用
+			if !dst.IsNil() {
+				return d.cpyStruct(dst.Elem(), src, depth)
+			}
+
+			// 被拷贝结构体是指针类型，值是空，
+			// 并且dst可以被设置值
+			// 直接malloc一块内存
+			if dst.Type().Elem().Kind() == reflect.Struct {
+				if dst.CanSet() {
+					p := reflect.New(dst.Type().Elem())
+					dst.Set(p)
+					return d.cpyStruct(dst.Elem(), src, depth)
+				}
+			}
 		}
 		return nil
 	}
diff --git a/deepcopy_dst_ptr_struct_test.go b/deepcopy_dst_ptr_struct_test.go
@@ -0,0 +1,35 @@
+package deepcopy
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type TestDstStructPtr_Dst struct {
+	TestDstPtr *struct {
+		X int
+		Y int
+	}
+}
+
+type TestDstPtr2 struct {
+	X int
+	Y int
+}
+
+type TestDstStructPtr_Src struct {
+	TestDstPtr TestDstPtr2
+}
+
+func Test_DstPtr_Struct(t *testing.T) {
+	var dst TestDstStructPtr_Dst
+	src := TestDstStructPtr_Src{
+		TestDstPtr: TestDstPtr2{X: 3, Y: 4},
+	}
+
+	Copy(&dst, &src).Do()
+	assert.NotNil(t, dst.TestDstPtr)
+	assert.Equal(t, dst.TestDstPtr.X, 3)
+	assert.Equal(t, dst.TestDstPtr.Y, 4)
+}

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,5 @@`
`1`	`1`	`# Binaries for programs and plugins`
	`2`	`+/cover.cov`
`2`	`3`	`*swp`
`3`	`4`	`*~`
`4`	`5`	`*.exe`