From cbe1eeb08cde008159f7d438f440e9cdbc10768f Mon Sep 17 00:00:00 2001
From: Roman Khimov <roman@nspcc.ru>
Date: Fri, 23 Jul 2021 11:46:26 +0300
Subject: [PATCH] smartcontract: add support for valueless Parameters

This is fine:
            {
               "type" : "Signature"
            },
---
 pkg/smartcontract/parameter.go | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/pkg/smartcontract/parameter.go b/pkg/smartcontract/parameter.go
index d961b191e..0702e17f8 100644
--- a/pkg/smartcontract/parameter.go
+++ b/pkg/smartcontract/parameter.go
@@ -109,7 +109,11 @@ func (p *Parameter) UnmarshalJSON(data []byte) (err error) {
 	if err = json.Unmarshal(data, &r); err != nil {
 		return
 	}
-	switch p.Type = r.Type; r.Type {
+	p.Type = r.Type
+	if len(r.Value) == 0 {
+		return
+	}
+	switch r.Type {
 	case BoolType:
 		if err = json.Unmarshal(r.Value, &boolean); err != nil {
 			return