From c11481b119a60920e71e26ab5e5429bc568aa702 Mon Sep 17 00:00:00 2001
From: Anna Shaleva <shaleva.ann@nspcc.ru>
Date: Mon, 5 Sep 2022 17:30:43 +0300
Subject: [PATCH] nns: allow hyphen in domain names

Port https://github.com/nspcc-dev/neofs-contract/pull/183.
---
 examples/nft-nd-nns/nns.go      | 8 +++++---
 examples/nft-nd-nns/nns_test.go | 6 ++++++
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/examples/nft-nd-nns/nns.go b/examples/nft-nd-nns/nns.go
index d5039d37b..f04c5525b 100644
--- a/examples/nft-nd-nns/nns.go
+++ b/examples/nft-nd-nns/nns.go
@@ -507,6 +507,8 @@ func checkCommittee() {
 }
 
 // checkFragment validates root or a part of domain name.
+// 1. Root domain must start with a letter.
+// 2. All other fragments must start and end in a letter or a digit.
 func checkFragment(v string, isRoot bool) bool {
 	maxLength := maxDomainNameFragmentLength
 	if isRoot {
@@ -525,12 +527,12 @@ func checkFragment(v string, isRoot bool) bool {
 			return false
 		}
 	}
-	for i := 1; i < len(v); i++ {
-		if !isAlNum(v[i]) {
+	for i := 1; i < len(v)-1; i++ {
+		if v[i] != '-' && !isAlNum(v[i]) {
 			return false
 		}
 	}
-	return true
+	return isAlNum(v[len(v)-1])
 }
 
 // isAlNum checks whether provided char is a lowercase letter or a number.
diff --git a/examples/nft-nd-nns/nns_test.go b/examples/nft-nd-nns/nns_test.go
index 1e80ed7ce..230aa7202 100644
--- a/examples/nft-nd-nns/nns_test.go
+++ b/examples/nft-nd-nns/nns_test.go
@@ -173,6 +173,12 @@ func TestRegisterAndRenew(t *testing.T) {
 	c.Invoke(t, false, "register", "neo.com", e.CommitteeHash)
 	c.Invoke(t, false, "isAvailable", "neo.com")
 
+	t.Run("domain names with hyphen", func(t *testing.T) {
+		c.InvokeFail(t, "invalid domain name format", "register", "-testdomain.com", e.CommitteeHash)
+		c.InvokeFail(t, "invalid domain name format", "register", "testdomain-.com", e.CommitteeHash)
+		c.Invoke(t, true, "register", "test-domain.com", e.CommitteeHash)
+	})
+
 	props := stackitem.NewMap()
 	props.Add(stackitem.Make("name"), stackitem.Make("neo.com"))
 	props.Add(stackitem.Make("expiration"), stackitem.Make(expectedExpiration))