From 3c8f8212208758768db3c04a04666637559a0ddc Mon Sep 17 00:00:00 2001
From: Md Junaed Hossain <169046794+junaed-optimizely@users.noreply.github.com>
Date: Thu, 4 Sep 2025 01:18:01 +0600
Subject: [PATCH 1/2] [FSSDK-11837] legacy api adjustment with key null support
 in deccide

---
 .../OptimizelyUserContextTest.cs                | 17 +++++++++++++++++
 OptimizelySDK/Optimizely.cs                     |  8 ++++++++
 2 files changed, 25 insertions(+)

diff --git a/OptimizelySDK.Tests/OptimizelyUserContextTest.cs b/OptimizelySDK.Tests/OptimizelyUserContextTest.cs
index 21ae10db..49b3a903 100644
--- a/OptimizelySDK.Tests/OptimizelyUserContextTest.cs
+++ b/OptimizelySDK.Tests/OptimizelyUserContextTest.cs
@@ -405,6 +405,23 @@ public void DecideInvalidFlagKey()
             Assert.IsTrue(TestData.CompareObjects(decision, decisionExpected));
         }
 
+        [Test]
+        public void DecideNullFlagKey()
+        {
+            var user = Optimizely.CreateUserContext(UserID);
+            user.SetAttribute("browser_type", "chrome");
+
+            var decisionExpected = OptimizelyDecision.NewErrorDecision(
+                null,
+                user,
+                DecisionMessage.Reason(DecisionMessage.FLAG_KEY_INVALID, "null"),
+                ErrorHandlerMock.Object,
+                LoggerMock.Object);
+            var decision = user.Decide(null);
+
+            Assert.IsTrue(TestData.CompareObjects(decision, decisionExpected));
+        }
+
         [Test]
         public void DecideWhenConfigIsNull()
         {
diff --git a/OptimizelySDK/Optimizely.cs b/OptimizelySDK/Optimizely.cs
index 23483360..56fd2d0c 100644
--- a/OptimizelySDK/Optimizely.cs
+++ b/OptimizelySDK/Optimizely.cs
@@ -870,6 +870,13 @@ OptimizelyDecideOption[] options
                     ErrorHandler, Logger);
             }
 
+            if (key == null)
+            {
+                return OptimizelyDecision.NewErrorDecision(key, user,
+                    DecisionMessage.Reason(DecisionMessage.FLAG_KEY_INVALID, "null"),
+                    ErrorHandler, Logger);
+            }
+
             var allOptions = GetAllOptions(options).
                 Where(opt => opt != OptimizelyDecideOption.ENABLED_FLAGS_ONLY).
                 ToArray();
@@ -930,6 +937,7 @@ internal Dictionary<string, OptimizelyDecision> DecideForKeys(OptimizelyUserCont
             foreach (var key in keys)
             {
                 var flag = projectConfig.GetFeatureFlagFromKey(key);
+
                 if (flag.Key == null)
                 {
                     decisionDictionary.Add(key,

From d9e48e032de16616d96b71cb325f09ca7a1f630e Mon Sep 17 00:00:00 2001
From: Md Junaed Hossain <169046794+junaed-optimizely@users.noreply.github.com>
Date: Thu, 4 Sep 2025 01:23:13 +0600
Subject: [PATCH 2/2] [FSSDK-11837] space removal

---
 OptimizelySDK/Optimizely.cs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/OptimizelySDK/Optimizely.cs b/OptimizelySDK/Optimizely.cs
index 56fd2d0c..bf70dafb 100644
--- a/OptimizelySDK/Optimizely.cs
+++ b/OptimizelySDK/Optimizely.cs
@@ -937,7 +937,6 @@ internal Dictionary<string, OptimizelyDecision> DecideForKeys(OptimizelyUserCont
             foreach (var key in keys)
             {
                 var flag = projectConfig.GetFeatureFlagFromKey(key);
-
                 if (flag.Key == null)
                 {
                     decisionDictionary.Add(key,