nns: keep isAvailable in sync with register

If conflicting records '*.domain' are present on new domain
registration, then `isAvailable` should return false for this
domain. Ref.
f25296b17a.

examples/nft-nd-nns/nns.go

@@ -208,7 +208,7 @@ func GetPrice() int {
 
 // IsAvailable checks whether provided domain name is available.
 func IsAvailable(name string) bool {
-	fragments := splitAndCheck(name, false)
+	fragments := splitAndCheck(name, true)
 	if fragments == nil {
 		panic("invalid domain name format")
 	}
@@ -220,7 +220,27 @@ func IsAvailable(name string) bool {
 		}
 		return true
 	}
-	return parentExpired(ctx, 0, fragments)
+	if !parentExpired(ctx, 0, fragments) {
+		return false
+	}
+	return len(getParentConflictingRecord(ctx, name, fragments)) == 0
+}
+
+// getPrentConflictingRecord returns record of '*.name' format if they are presented.
+// These records conflict with domain name to be registered.
+func getParentConflictingRecord(ctx storage.Context, name string, fragments []string) string {
+	parentKey := getTokenKey([]byte(name[len(fragments[0])+1:]))
+	parentRecKey := append([]byte{prefixRecord}, parentKey...)
+	it := storage.Find(ctx, parentRecKey, storage.ValuesOnly|storage.DeserializeValues)
+	suffix := []byte(name)
+	for iterator.Next(it) {
+		r := iterator.Value(it).(RecordState)
+		ind := std.MemorySearchLastIndex([]byte(r.Name), suffix, len(r.Name))
+		if ind > 0 && ind+len(suffix) == len(r.Name) {
+			return r.Name
+		}
+	}
+	return ""
 }
 
 // parentExpired returns true if any domain from fragments doesn't exist or expired.
@@ -273,15 +293,8 @@ func Register(name string, owner interop.Hash160, email string, refresh, retry,
 		ns := std.Deserialize(nsBytes.([]byte)).(NameState)
 		ns.checkAdmin()
 
-		parentRecKey := append([]byte{prefixRecord}, parentKey...)
+		if conflict := getParentConflictingRecord(ctx, name, fragments); len(conflict) != 0 {
-		it := storage.Find(ctx, parentRecKey, storage.ValuesOnly|storage.DeserializeValues)
+			panic("parent domain has conflicting records: " + conflict)
-		suffix := []byte(name)
-		for iterator.Next(it) {
-			r := iterator.Value(it).(RecordState)
-			ind := std.MemorySearchLastIndex([]byte(r.Name), suffix, len(r.Name))
-			if ind > 0 && ind+len(suffix) == len(r.Name) {
-				panic("parent domain has conflicting records: " + r.Name)
-			}
 		}
 	}
 

examples/nft-nd-nns/nns_test.go

@@ -125,29 +125,15 @@ func TestExpiration(t *testing.T) {
 	require.NoError(t, bc.AddBlock(e.SignBlock(b2)))
 	e.CheckHalt(t, tx.Hash(), stackitem.NewBool(true))
 
-	tx = cAcc.PrepareInvoke(t, "isAvailable", "first.com")
+	b3 := e.NewUnsignedBlock(t)
-	b3 := e.NewUnsignedBlock(t, tx)
 	b3.Index = b2.Index + 1
 	b3.PrevHash = b2.Hash()
-	b3.Timestamp = b1.Timestamp + (uint64(expire)*1000 + 1)
+	b3.Timestamp = b1.Timestamp + (uint64(expire) * 1000)
 	require.NoError(t, bc.AddBlock(e.SignBlock(b3)))
-	e.CheckHalt(t, tx.Hash(), stackitem.NewBool(true)) // "first.com" has been expired
 
-	tx = cAcc.PrepareInvoke(t, "isAvailable", "second.com")
+	cAcc.Invoke(t, true, "isAvailable", "first.com")  // "first.com" has been expired
-	b4 := e.NewUnsignedBlock(t, tx)
+	cAcc.Invoke(t, true, "isAvailable", "second.com") // TLD "com" has been expired
-	b4.Index = b3.Index + 1
+	cAcc.InvokeFail(t, "name has expired", "getRecords", "first.com", int64(nns.TXT))
-	b4.PrevHash = b3.Hash()
-	b4.Timestamp = b3.Timestamp + 1000
-	require.NoError(t, bc.AddBlock(e.SignBlock(b4)))
-	e.CheckHalt(t, tx.Hash(), stackitem.NewBool(true)) // TLD "com" has been expired
-
-	tx = cAcc.PrepareInvoke(t, "getRecords", "first.com", int64(nns.TXT))
-	b5 := e.NewUnsignedBlock(t, tx)
-	b5.Index = b4.Index + 1
-	b5.PrevHash = b4.Hash()
-	b5.Timestamp = b4.Timestamp + 1000
-	require.NoError(t, bc.AddBlock(e.SignBlock(b5)))
-	e.CheckFault(t, tx.Hash(), "name has expired")
 
 	// TODO: According to the new code, we can't re-register expired "com" TLD, because it's already registered; at the
 	// same time we can't renew it because it's already expired. We likely need to change this logic in the contract and
@@ -629,11 +615,13 @@ func TestNNSRegisterArbitraryLevelDomain(t *testing.T) {
 		"another.fs.neo.com", int64(nns.A), "4.3.2.1")
 
 	c2 = c.WithSigners(acc, acc2)
+	c2.Invoke(t, stackitem.NewBool(false), "isAvailable", "mainnet.fs.neo.com")
 	c2.InvokeFail(t, "parent domain has conflicting records: something.mainnet.fs.neo.com",
 		"register", args...)
 
 	c1.Invoke(t, stackitem.Null{}, "deleteRecords",
 		"something.mainnet.fs.neo.com", int64(nns.A))
+	c2.Invoke(t, stackitem.NewBool(true), "isAvailable", "mainnet.fs.neo.com")
 	c2.Invoke(t, true, "register", args...)
 
 	c2 = c.WithSigners(acc2)