From 29f589b54e3962356fcef524805aafe8b84863d1 Mon Sep 17 00:00:00 2001
From: Leonard Lyubich <leonard@nspcc.ru>
Date: Fri, 26 Nov 2021 14:03:27 +0300
Subject: [PATCH] [#94] subnet: Add methods to check subnet owner and ID

Implement `IsOwner` and `IDEquals` functions which check the
correspondence of the fields in `Info`. Remove no longer needed
`HasOwner` method of `Info`.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
---
 subnet/subnet.go      | 35 +++++++++++++++++++++++++++--------
 subnet/subnet_test.go | 38 ++++++++++++++------------------------
 2 files changed, 41 insertions(+), 32 deletions(-)

diff --git a/subnet/subnet.go b/subnet/subnet.go
index 996f449c..f70f8763 100644
--- a/subnet/subnet.go
+++ b/subnet/subnet.go
@@ -76,17 +76,36 @@ func (x *Info) SetOwner(id owner.ID) {
 	*idv2 = *id.ToV2()
 }
 
-// HasOwner checks if subnet owner is set.
-func (x Info) HasOwner() bool {
-	return (*subnet.Info)(&x).Owner() != nil
-}
-
 // ReadOwner reads the identifier of the subnet that Info describes.
 // Must be called only if owner is set (see HasOwner). Arg must not be nil.
 func (x Info) ReadOwner(id *owner.ID) {
 	infov2 := (subnet.Info)(x)
 
-	// FIXME: we need to implement and use owner.ID.FromV2 method
-	id2 := owner.NewIDFromV2(infov2.Owner())
-	*id = *id2
+	id2 := infov2.Owner()
+	if id2 == nil {
+		// TODO: implement owner.ID.Reset
+		*id = owner.ID{}
+		return
+	}
+
+	// TODO: we need to implement and use owner.ID.FromV2 method
+	*id = *owner.NewIDFromV2(infov2.Owner())
+}
+
+// IsOwner checks subnet ownership.
+func IsOwner(info Info, id owner.ID) bool {
+	id2 := new(owner.ID)
+
+	info.ReadOwner(id2)
+
+	return id.Equal(id2)
+}
+
+// IDEquals checks if ID refers to subnet that Info describes.
+func IDEquals(info Info, id subnetid.ID) bool {
+	id2 := new(subnetid.ID)
+
+	info.ReadID(id2)
+
+	return id.Equals(id2)
 }
diff --git a/subnet/subnet_test.go b/subnet/subnet_test.go
index 763cb71b..438bfb40 100644
--- a/subnet/subnet_test.go
+++ b/subnet/subnet_test.go
@@ -7,61 +7,51 @@ import (
 	subnettest "github.com/nspcc-dev/neofs-api-go/v2/subnet/test"
 	"github.com/nspcc-dev/neofs-sdk-go/owner"
 	ownertest "github.com/nspcc-dev/neofs-sdk-go/owner/test"
-	"github.com/nspcc-dev/neofs-sdk-go/subnet"
+	. "github.com/nspcc-dev/neofs-sdk-go/subnet"
 	subnetid "github.com/nspcc-dev/neofs-sdk-go/subnet/id"
 	"github.com/stretchr/testify/require"
 )
 
 func TestInfoZero(t *testing.T) {
-	var info subnet.Info
+	var info Info
 
 	var id subnetid.ID
 	info.ReadID(&id)
 
 	require.True(t, subnetid.IsZero(id))
-
-	require.False(t, info.HasOwner())
 }
 
 func TestInfo_SetID(t *testing.T) {
 	var (
-		idFrom, idTo subnetid.ID
-
-		info subnet.Info
+		id   subnetid.ID
+		info Info
 	)
 
-	idFrom.SetNumber(222)
+	id.SetNumber(222)
 
-	info.SetID(idFrom)
+	info.SetID(id)
 
-	info.ReadID(&idTo)
-
-	require.True(t, idTo.Equals(&idFrom))
+	require.True(t, IDEquals(info, id))
 }
 
 func TestInfo_SetOwner(t *testing.T) {
 	var (
-		idFrom, idTo owner.ID
-
-		info subnet.Info
+		id   owner.ID
+		info Info
 	)
 
-	idFrom = *ownertest.GenerateID()
+	id = *ownertest.GenerateID()
 
-	require.False(t, info.HasOwner())
+	require.False(t, IsOwner(info, id))
 
-	info.SetOwner(idFrom)
+	info.SetOwner(id)
 
-	require.True(t, info.HasOwner())
-
-	info.ReadOwner(&idTo)
-
-	require.True(t, idTo.Equal(&idFrom))
+	require.True(t, IsOwner(info, id))
 }
 
 func TestInfo_WriteToV2(t *testing.T) {
 	var (
-		infoTo, infoFrom subnet.Info
+		infoTo, infoFrom Info
 
 		infoV2From, infoV2To subnetv2.Info
 	)