Fix tests and PR feedback

Author: ErikEJ

src/Microsoft.Data.SqlClient/src/Microsoft/Data/Common/AdapterUtil.cs

@@ -24,8 +24,6 @@
 using Microsoft.Identity.Client;
 using Microsoft.SqlServer.Server;
 using System.Security.Authentication;
-using System.Linq;
-
 
 #if NETFRAMEWORK
 using System.Reflection;
@@ -791,18 +789,17 @@ internal static Version GetAssemblyVersion()
         /// </summary>
         /// <remarks>This array contains predefined endpoint strings used to identify Azure Synapse and
         /// associated services, such as Fabric Data Warehouse and Power BI Data Warehouse.</remarks>
-        internal static readonly string[] s_azureSynapseEndpoints = { AZURE_SYNAPSE,
-                                                                      FABRIC_DATAWAREHOUSE,
+        internal static readonly string[] s_azureSynapseEndpoints = { FABRIC_DATAWAREHOUSE,
                                                                       PBI_DATAWAREHOUSE,
                                                                       PBI_DATAWAREHOUSE2,
                                                                       PBI_DATAWAREHOUSE3 };
 
-        internal static readonly string[] s_azureSynapseOnDemandEndpoints = s_azureSqlServerOnDemandEndpoints
-                                                                            .Concat(s_azureSynapseEndpoints)
-                                                                            .ToArray();
+        internal static readonly string[] s_azureSynapseOnDemandEndpoints = [.. s_azureSqlServerOnDemandEndpoints, .. s_azureSynapseEndpoints];
+
         internal static bool IsAzureSynapseOnDemandEndpoint(string dataSource)
         {
-            return IsEndpoint(dataSource, s_azureSynapseOnDemandEndpoints);
+            return IsEndpoint(dataSource, s_azureSynapseOnDemandEndpoints)
+                || dataSource.IndexOf(AZURE_SYNAPSE, StringComparison.OrdinalIgnoreCase) >= 0; 
         }
 
         internal static bool IsAzureSqlServerEndpoint(string dataSource)
@@ -846,7 +843,7 @@ private static bool IsEndpoint(string dataSource, string[] endpoints)
             // check if servername ends with any endpoints
             foreach (var endpoint in endpoints)
             {
-                if (length > endpoint.Length)
+                if (length >= endpoint.Length)
                 {
                     if (string.Compare(dataSource, length - endpoint.Length, endpoint, 0, endpoint.Length, StringComparison.OrdinalIgnoreCase) == 0)
                     {

src/Microsoft.Data.SqlClient/tests/FunctionalTests/SqlConnectionTest.cs

@@ -1100,6 +1100,7 @@ public void ConnectionString_WithOnlyComma()
         [InlineData("myserver.database.windows.net")]
         [InlineData("myserver.database.cloudapi.de")]
         [InlineData("myserver.database.usgovcloudapi.net")]
+        [InlineData("myserver.DATABASE.usgovcloudapi.net")]
         [InlineData("myserver.database.chinacloudapi.cn")]
         [InlineData("myserver.database.fabric.microsoft.com")]
         public void ConnectionRetryForAzureDbEndpoints(string serverName)
@@ -1112,8 +1113,10 @@ public void ConnectionRetryForAzureDbEndpoints(string serverName)
 
         [Theory]
         [InlineData("myserver-ondemand.sql.azuresynapse.net")]
+        [InlineData("myserver-ondemand.SQL.azuresynapse.net")]
         [InlineData("someserver-ondemand.database.windows.net")]
         [InlineData("datawarehouse.fabric.microsoft.com")]
+        [InlineData("datawarehouse.FABRIC.microsoft.com")]
         [InlineData("datawarehouse.pbidedicated.microsoft.com")]
         [InlineData("someserver.pbidedicated.microsoft.com")]
         [InlineData("someserver.pbidedicated.windows.net")]