Index: tests/natools-s_expressions-cache_tests.adb
==================================================================
--- tests/natools-s_expressions-cache_tests.adb
+++ tests/natools-s_expressions-cache_tests.adb
@@ -72,10 +72,11 @@
 
    procedure All_Tests (Report : in out NT.Reporter'Class) is
    begin
       Default_Instantiation (Report);
       Debug_Instantiation (Report);
+      Descriptor_Interface (Report);
    end All_Tests;
 
 
    -----------------------
    -- Inidividual Tests --
@@ -226,6 +227,55 @@
       end;
    exception
       when Error : others => Test.Report_Exception (Error);
    end Default_Instantiation;
 
+
+   procedure Descriptor_Interface (Report : in out NT.Reporter'Class) is
+      Test : NT.Test := Report.Item ("Descriptor insterface");
+   begin
+      declare
+         Cache : Caches.Reference;
+         First, Second : Caches.Cursor;
+      begin
+         Cache.Append_Atom (To_Atom ("begin"));
+         Cache.Open_List;
+         Cache.Append_Atom (To_Atom ("command"));
+         Cache.Open_List;
+         Cache.Append_Atom (To_Atom ("first"));
+         Cache.Append_Atom (To_Atom ("second"));
+         Cache.Close_List;
+         Cache.Close_List;
+         Cache.Append_Atom (To_Atom ("end"));
+
+         First := Cache.First;
+         Second := First;
+
+         Test_Tools.Test_Atom_Accessors (Test, First, To_Atom ("begin"), 0);
+         Test_Tools.Test_Atom_Accessors (Test, Second, To_Atom ("begin"), 0);
+
+         Test_Tools.Next_And_Check (Test, First, Events.Open_List, 1);
+         Test_Tools.Test_Atom_Accessor_Exceptions (Test, First);
+         Test_Tools.Next_And_Check (Test, First, To_Atom ("command"), 1);
+         Test_Tools.Next_And_Check (Test, First, Events.Open_List, 2);
+         Test_Tools.Next_And_Check (Test, Second, Events.Open_List, 1);
+         Test_Tools.Next_And_Check (Test, First, To_Atom ("first"), 2);
+         Test_Tools.Next_And_Check (Test, Second, To_Atom ("command"), 1);
+         Test_Tools.Next_And_Check (Test, First, To_Atom ("second"), 2);
+         Test_Tools.Next_And_Check (Test, First, Events.Close_List, 1);
+         Test_Tools.Next_And_Check (Test, Second, Events.Open_List, 2);
+         Test_Tools.Next_And_Check (Test, Second, To_Atom ("first"), 2);
+         Test_Tools.Next_And_Check (Test, Second, To_Atom ("second"), 2);
+         Test_Tools.Next_And_Check (Test, First, Events.Close_List, 0);
+         Test_Tools.Next_And_Check (Test, Second, Events.Close_List, 1);
+         Test_Tools.Test_Atom_Accessor_Exceptions (Test, Second);
+         Test_Tools.Next_And_Check (Test, Second, Events.Close_List, 0);
+         Test_Tools.Next_And_Check (Test, Second, To_Atom ("end"), 0);
+         Test_Tools.Next_And_Check (Test, First, To_Atom ("end"), 0);
+         Test_Tools.Next_And_Check (Test, First, Events.End_Of_Input, 0);
+         Test_Tools.Next_And_Check (Test, Second, Events.End_Of_Input, 0);
+      end;
+   exception
+      when Error : others => Test.Report_Exception (Error);
+   end Descriptor_Interface;
+
 end Natools.S_Expressions.Cache_Tests;

Index: tests/natools-s_expressions-cache_tests.ads
==================================================================
--- tests/natools-s_expressions-cache_tests.ads
+++ tests/natools-s_expressions-cache_tests.ads
@@ -28,7 +28,8 @@
 
    procedure All_Tests (Report : in out NT.Reporter'Class);
 
    procedure Debug_Instantiation (Report : in out NT.Reporter'Class);
    procedure Default_Instantiation (Report : in out NT.Reporter'Class);
+   procedure Descriptor_Interface (Report : in out NT.Reporter'Class);
 
 end Natools.S_Expressions.Cache_Tests;