[Testing] Demo Test

global.json

@@ -3,7 +3,7 @@
     "Microsoft.Build.Traversal": "3.2.0"
   },
   "sdk": {
-    "version": "8.0.100",
+    "version": "9.0.102",
     "rollForward": "feature"
   }
 }

sdk/communication/Azure.Communication.Common/src/JwtTokenParser.cs

@@ -19,19 +19,25 @@ public static AccessToken CreateAccessToken(string token)
 
         internal static JwtPayload DecodeJwtPayload(string token)
         {
-            const string TokenNotFormattedCorrectly = "Token is not formatted correctly.";
+            const string TokenPartsIncorrect = "Token does not have the correct number of parts.";
+            const string TokenPayloadIncorrect = "Token payload is not formatted correctly.";
 
             var tokenParts = token.Split('.');
-            if (tokenParts.Length < 2)
-                throw new FormatException(TokenNotFormattedCorrectly);
+            if (tokenParts.Length != 3)
+                throw new FormatException(TokenPartsIncorrect);
 
             try
             {
-                return JsonSerializer.Deserialize<JwtPayload>(Base64Url.DecodeString(tokenParts[1]));
+                var payloadJson = Base64Url.DecodeString(tokenParts[1]);
+                return JsonSerializer.Deserialize<JwtPayload>(payloadJson) ?? throw new FormatException(TokenPayloadIncorrect);
             }
             catch (JsonException ex)
             {
-                throw new FormatException(TokenNotFormattedCorrectly, ex);
+                throw new FormatException(TokenPayloadIncorrect, ex);
+            }
+            catch (ArgumentException ex)
+            {
+                throw new FormatException(TokenPayloadIncorrect, ex);
             }
         }
 

sdk/communication/Azure.Communication.Common/tests/JwtTokenParserTests.cs

@@ -0,0 +1,26 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+using System;
+using Azure.Communication;
+using NUnit.Framework;
+
+namespace Azure.Communication
+{
+    public class JwtTokenParserTests
+    {
+        [Test]
+        public void DecodeJwtPayload_WithInvalidBase64String_ShouldThrowFormatException()
+        {
+            string invalidBase64UrlString = "Invalid_Base64_String";
+            Assert.Throws<FormatException>(() => JwtTokenParser.DecodeJwtPayload(invalidBase64UrlString), "Token payload is not formatted correctly.");
+        }
+
+        [Test]
+        public void DecodeJwtPayload_WithInvalidTokenParts_ShouldThrowFormatException()
+        {
+            string invalidToken = "Invalid.Token";
+            Assert.Throws<FormatException>(() => JwtTokenParser.DecodeJwtPayload(invalidToken), "Token does not have the correct number of parts.");
+        }
+    }
+}