From 8d2651b33d6f3f65aaecf1cc8bf78adda47dcbac Mon Sep 17 00:00:00 2001
From: Michael Grafnetter <michael.grafnetter@outlook.com>
Date: Wed, 4 Mar 2020 23:13:21 +0100
Subject: [PATCH] Improved DN parsing

---
 Src/DSInternals.Common.Test/DistinguishedNameTester.cs | 7 +++++++
 Src/DSInternals.Common/Data/DistinguishedName.cs       | 5 ++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/Src/DSInternals.Common.Test/DistinguishedNameTester.cs b/Src/DSInternals.Common.Test/DistinguishedNameTester.cs
index 631fe3c..647cb9d 100644
--- a/Src/DSInternals.Common.Test/DistinguishedNameTester.cs
+++ b/Src/DSInternals.Common.Test/DistinguishedNameTester.cs
@@ -289,5 +289,12 @@
             var dn = new DistinguishedName("OU=Employees,OU=Marketing,DC=adatum,DC=com");
             Assert.AreEqual("DC=adatum,DC=com", dn.RootNamingContext.ToString());
         }
+
+        [TestMethod]
+        public void DistinguishedName_RootNamingContext_Vector3()
+        {
+            var dn = new DistinguishedName("DC=LON-CL1,cn=MicrosoftDNS,DC=DomainDnsZones,DC=adatum,DC=com");
+            Assert.AreEqual("DC=DomainDnsZones,DC=adatum,DC=com", dn.RootNamingContext.ToString());
+        }
     }
 }
diff --git a/Src/DSInternals.Common/Data/DistinguishedName.cs b/Src/DSInternals.Common/Data/DistinguishedName.cs
index 5e30336..d1a03e9 100644
--- a/Src/DSInternals.Common/Data/DistinguishedName.cs
+++ b/Src/DSInternals.Common/Data/DistinguishedName.cs
@@ -96,7 +96,10 @@
         {
             get
             {
-                var dcComponents = this.components.Where(component => component.Name.Equals(CommonDirectoryAttributes.DomainComponent, StringComparison.InvariantCultureIgnoreCase));
+                var dcComponents = this.components
+                    .Reverse<DistinguishedNameComponent>()
+                    .TakeWhile(component => component.Name.Equals(CommonDirectoryAttributes.DomainComponent, StringComparison.InvariantCultureIgnoreCase))
+                    .Reverse();
                 var result = new DistinguishedName();
                 result.components.AddRange(dcComponents);
                 return result;