test(proto): add storage node descriptor validation tests

- Added new file: proto/varlogpb/storage_node_test.go
- Includes tests for StorageNodeDescriptor validation

proto/varlogpb/storage_node_test.go

@@ -0,0 +1,62 @@
+package varlogpb_test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/kakao/varlog/proto/varlogpb"
+)
+
+func TestStorageNodeDescriptor_Valid(t *testing.T) {
+	tcs := []struct {
+		name string
+		snd  *varlogpb.StorageNodeDescriptor
+		want bool
+	}{
+		{
+			name: "Valid",
+			snd: &varlogpb.StorageNodeDescriptor{
+				StorageNode: varlogpb.StorageNode{StorageNodeID: 1, Address: "127.0.0.1"},
+				Paths:       []string{"/path/to/storage"},
+			},
+			want: true,
+		},
+		{
+			name: "NilDescriptor",
+			snd:  nil,
+			want: false,
+		},
+		{
+			name: "EmptyAddress",
+			snd: &varlogpb.StorageNodeDescriptor{
+				StorageNode: varlogpb.StorageNode{StorageNodeID: 1, Address: ""},
+				Paths:       []string{"/path/to/storage"},
+			},
+			want: false,
+		},
+		{
+			name: "EmptyPaths",
+			snd: &varlogpb.StorageNodeDescriptor{
+				StorageNode: varlogpb.StorageNode{StorageNodeID: 1, Address: "127.0.0.1"},
+				Paths:       []string{},
+			},
+			want: false,
+		},
+		{
+			name: "EmptyPathInPaths",
+			snd: &varlogpb.StorageNodeDescriptor{
+				StorageNode: varlogpb.StorageNode{StorageNodeID: 1, Address: "127.0.0.1"},
+				Paths:       []string{""},
+			},
+			want: false,
+		},
+	}
+
+	for _, tc := range tcs {
+		t.Run(tc.name, func(t *testing.T) {
+			got := tc.snd.Valid()
+			require.Equal(t, tc.want, got)
+		})
+	}
+}