Hello,

In some cases, I need to pass the dst interface for copy, could Copy(src, dst interface{}) be supported?

When running the go vet tool on the test cases, the following problems are being reported:

deepcopy_test.go:978: arg copyB.Epsilon[k] for printf verb %d of wrong type: *utils.Bar
deepcopy_test.go:982: arg v for printf verb %d of wrong type: *utils.Bar
deepcopy_test.go:986: arg copyB.Epsilon[k].Beta for printf verb %d of wrong type: string
deepcopy_test.go:989: missing argument for Errorf("%d"): format reads arg 3, have only 2 args
deepcopy_test.go:995: arg copyB.Epsilon[k].Delta for printf verb %d of wrong type: *utils.Foo
deepcopy_test.go:1002: arg v.Delta.Alpha for printf verb %d of wrong type: string
deepcopy_test.go:1042: possible formatting directive in Error call

Just found this repo.

@mohae are you still maintaining this?

• add support for go module?
• release a versioned tag?

Feel free to close this.
❤️

When I call deepcopy method, i am facing issue.
===================METHOD==================
response.BdtReqData = deepcopy.Copy(&request).(*models.BdtReqData)

=====================BdtReqData========================
package models

type BdtReqData struct {
AspId string json:"aspId" yaml:"aspId" bson:"aspId" mapstructure:"AspId"
DesTimeInt *TimeWindow json:"desTimeInt" yaml:"desTimeInt" bson:"desTimeInt" mapstructure:"DesTimeInt"
NwAreaInfo *NetworkAreaInfo json:"nwAreaInfo,omitempty" yaml:"nwAreaInfo" bson:"nwAreaInfo" mapstructure:"NwAreaInfo"
NumOfUes int32 json:"numOfUes" yaml:"numOfUes" bson:"numOfUes" mapstructure:"NumOfUes"
VolPerUe *UsageThreshold json:"volPerUe" yaml:"volPerUe" bson:"volPerUe" mapstructure:"VolPerUe"
SuppFeat string json:"suppFeat,omitempty" yaml:"suppFeat" bson:"suppFeat" mapstructure:"SuppFeat"
}

==================Request Restful API Call===========================
curl -X 'POST'
'http://127.0.0.7:8000/npcf-bdtpolicycontrol/v1/bdtpolicies'
-H 'accept: application/json'
-H 'Content-Type: application/json'
-d '{
"aspId": "ASP001",
"desTimeInt": {
"startTime": "2021-09-25T18:07:00.083Z",
"stopTime": "2021-09-26T21:09:45.083Z"
},
"numOfUes": 3,
"volPerUe": {
"duration": 360,
"totalVolume": 1024,
"downlinkVolume": 512,
"uplinkVolume": 512
}
}'
================Error=============================
2021/09/29 10:10:34 [Recovery] 2021/09/29 - 10:10:34 panic recovered:
interface conversion: interface {} is **models.BdtReqData, not *models.BdtReqData
/usr/local/go/src/runtime/iface.go:260 (0x409b71)
panicdottypeE: panic(&TypeAssertionError{iface, have, want, ""})

Map keys are shallow-copied here: https://github.com/mohae/deepcopy/blob/master/deepcopy.go#L103

This should normally not affect any real world code as slices/maps are forbidden in map keys and pointers have no "one true correct handling" for map keys: if one deep-copies them, lookups by the original pointers won't match anymore, and if one shallow-copies them, code modifying the copy may change the original.

I suggest explicitly detecting pointers inside map keys (recursively, as they could be struct fields) and panicking when attempting to deep-copy such values. The detection result could be cached by the map key type to prevent unnecessary processing.

At the very least though, this should be documented.

Hello,

I got an error in my case:

package main

import (
	"fmt"
	"github.com/mohae/deepcopy"
)

type A struct {
	Id uint32
}

type B struct {
	Id   string
	Data *A
}

func (p *A) DeepCopy() interface{} {
	if p == nil {
		return nil
	}
	c := *p
	return &c
}

func main() {
	b := &B{Id: "b"}
	c := deepcopy.Copy(b)
	fmt.Println(c)
}

My fix is to add a nil check here

	if original.CanInterface() {
		if copier, ok := original.Interface().(Interface); ok {
			// return if copier is nil
			if reflect.ValueOf(copier).IsNil() {
				return
			}
			cpy.Set(reflect.ValueOf(copier.DeepCopy()))
			return
		}
	}

your code can't copy error varible.

is there method to deep copy unexported field in struct?

Hello!

Somehow Copy function cannot deepcopy an array of list of list.
A example test is following.

package deepcopytest

import (
	"testing"

	"github.com/mohae/deepcopy"
)

type a [3][][]float64

var source = a{
	{
		{
			1.0,
			2.0,
			3.0,
		},
	},
}

func TestDeepcopy(t *testing.T) {
	distination := deepcopy.Copy(source).(a)
	source[0][0][0] = 4.0
	source[0][0][1] = 5.0
	source[0][0][2] = 6.0

	if distination[0][0][0] == source[0][0][0] {
		t.Fatal("Isn't deepcopied!", distination, source)
	}
}

Please make it can deepcopy.
Thank you.

Hello,

I have implemented DeepCopy method for my model as follows:

func (p *Version) DeepCopy() interface{} {
	c := *p
	return &c
}

I did a stress test, it turned out id doesn't improve the performance even if I implemented DeepCopy.

Did I miss something?

For unit testing/mock purpose I need to copy struct to an existing pointer instance.

For example I have:

func Get(key int, val interace{}) error {
  //...
  return nil
}

In the mock I would like to do:

func Get(key int, val interace{}) error {
  deepcopy.CopyRecursive(someVal, val)
  return nil
}

Any reasons to exclude copyRecursive() from exporting?

hi,

I would like to use you package. However some structs in my application contain (exported) time.Time fields.

Would you know how to have those fields copied by your library? More generally, how to integrate a custom copy?

cpy.Set(reflect.MakeSlice(original.Type(), original.Len(), original.Cap()))

set cpy fixed length

for i := 0; i < original.Len(); i++ {
	copyRecursive(original.Index(i), cpy.Index(i))
}

If original grows , will cpy overflow? original‘s source object is a pointer.