From f503027356d553681aa211afb012b4c314a9f4b8 Mon Sep 17 00:00:00 2001
From: Shargon <shargon@gmail.com>
Date: Thu, 28 Jan 2021 22:37:10 +0100
Subject: [PATCH] Fix tx attributes (#2276)

* Fix tx attributes

* Optimize

* Optimize

* Remove reflection

Co-authored-by: Erik Zhang <erik@neo.org>
---
 src/neo/Network/P2P/Payloads/Transaction.cs   | 11 ++++----
 .../Network/P2P/Payloads/UT_Transaction.cs    | 25 +++++++++++++++++++
 2 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/neo/Network/P2P/Payloads/Transaction.cs b/src/neo/Network/P2P/Payloads/Transaction.cs
index 5d8ffa4b3a..5ec7297fb2 100644
--- a/src/neo/Network/P2P/Payloads/Transaction.cs
+++ b/src/neo/Network/P2P/Payloads/Transaction.cs
@@ -220,14 +220,15 @@ void IInteroperable.FromStackItem(StackItem stackItem)
 
         public T GetAttribute<T>() where T : TransactionAttribute
         {
-            return GetAttributes<T>()?.First();
+            return GetAttributes<T>().FirstOrDefault();
         }
 
-        public T[] GetAttributes<T>() where T : TransactionAttribute
+        public IEnumerable<T> GetAttributes<T>() where T : TransactionAttribute
         {
-            _attributesCache ??= attributes.GroupBy(p => p.GetType()).ToDictionary(p => p.Key, p => (TransactionAttribute[])p.OfType<T>().ToArray());
-            _attributesCache.TryGetValue(typeof(T), out var result);
-            return (T[])result;
+            _attributesCache ??= attributes.GroupBy(p => p.GetType()).ToDictionary(p => p.Key, p => p.ToArray());
+            if (_attributesCache.TryGetValue(typeof(T), out var result))
+                return result.OfType<T>();
+            return Enumerable.Empty<T>();
         }
 
         public override int GetHashCode()
diff --git a/tests/neo.UnitTests/Network/P2P/Payloads/UT_Transaction.cs b/tests/neo.UnitTests/Network/P2P/Payloads/UT_Transaction.cs
index 77d4d5f750..d9e4cab9b8 100644
--- a/tests/neo.UnitTests/Network/P2P/Payloads/UT_Transaction.cs
+++ b/tests/neo.UnitTests/Network/P2P/Payloads/UT_Transaction.cs
@@ -1072,6 +1072,31 @@ public void ToJson()
             jObj["sysfee"].AsString().Should().Be("4200000000");
         }
 
+        [TestMethod]
+        public void Test_GetAttribute()
+        {
+            var tx = new Transaction()
+            {
+                Attributes = Array.Empty<TransactionAttribute>(),
+                NetworkFee = 0,
+                Nonce = (uint)Environment.TickCount,
+                Script = new byte[Transaction.MaxTransactionSize],
+                Signers = new Signer[] { new Signer() { Account = UInt160.Zero } },
+                SystemFee = 0,
+                ValidUntilBlock = 0,
+                Version = 0,
+                Witnesses = new Witness[0],
+            };
+
+            Assert.IsNull(tx.GetAttribute<OracleResponse>());
+            Assert.IsNull(tx.GetAttribute<HighPriorityAttribute>());
+
+            tx.Attributes = new TransactionAttribute[] { new HighPriorityAttribute() };
+
+            Assert.IsNull(tx.GetAttribute<OracleResponse>());
+            Assert.IsNotNull(tx.GetAttribute<HighPriorityAttribute>());
+        }
+
         [TestMethod]
         public void Test_VerifyStateIndependent()
         {