Add getaddr null backend test (#1138)

pkg/backends/null_test.go

@@ -0,0 +1,32 @@
+package backends
+
+import "testing"
+
+func TestNullBackendCfgGetAddr(t *testing.T) {
+	type fields struct {
+		Local bool
+	}
+	tests := []struct {
+		name   string
+		fields fields
+		want   string
+	}{
+		{
+			name: "Positive",
+			fields: fields{
+				Local: true,
+			},
+			want: "",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			cfg := &NullBackendCfg{
+				Local: tt.fields.Local,
+			}
+			if got := cfg.GetAddr(); got != tt.want {
+				t.Errorf("NullBackendCfg.GetAddr() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}