Make Diff.Compare() able to compare null Trees

1 files changed, 4 insertions, 4 deletions

diff --git a/LibGit2Sharp/Diff.cs b/LibGit2Sharp/Diff.cs
index 0e8b4742..0d39e79a 100644
--- a/LibGit2Sharp/Diff.cs
+++ b/LibGit2Sharp/Diff.cs
@@ -70,11 +70,11 @@ namespace LibGit2Sharp
         /// <returns>A <see cref = "TreeChanges"/> containing the changes between the <paramref name = "oldTree"/> and the <paramref name = "newTree"/>.</returns>
         public virtual TreeChanges Compare(Tree oldTree, Tree newTree, IEnumerable<string> paths = null)
         {
-            Ensure.ArgumentNotNull(oldTree, "oldTree");
-            Ensure.ArgumentNotNull(oldTree, "newTree");
-
             using(GitDiffOptions options = BuildOptions(paths))
-            using (DiffListSafeHandle diff = BuildDiffListFromTrees(oldTree.Id, newTree.Id, options))
+            using (DiffListSafeHandle diff = BuildDiffListFromTrees(
+                oldTree != null ? oldTree.Id : null,
+                newTree != null ? newTree.Id : null,
+                options))
             {
                 return new TreeChanges(diff);
             }