U126-028 Don't keep Ada_Node in the global name index

to prevent STALE_REFERENCE_ERROR. Replace Ada_Node with node's
Source_Location and find corresponding node at the query time
(it could be costly however).

Close #633

Author: reznikmm

source/ada/lsp-ada_contexts.adb

@@ -505,9 +505,43 @@ package body LSP.Ada_Contexts is
       Callback : not null access procedure
         (URI  : LSP.Messages.DocumentUri;
          Name : Libadalang.Analysis.Defining_Name;
-         Stop : in out Boolean)) is
+         Stop : in out Boolean))
+   is
+      procedure Adapter
+        (URI  : LSP.Messages.DocumentUri;
+         Loc  : Langkit_Support.Slocs.Source_Location;
+         Stop : in out Boolean);
+      --  Find a Defining_Name at the given location Loc in a unit of URI and
+      --  pass it to Callback procedure call.
+
+      -------------
+      -- Adapter --
+      -------------
+
+      procedure Adapter
+        (URI  : LSP.Messages.DocumentUri;
+         Loc  : Langkit_Support.Slocs.Source_Location;
+         Stop : in out Boolean)
+      is
+         Unit : constant Libadalang.Analysis.Analysis_Unit :=
+           LSP.Preprocessor.Get_From_File
+             (Self.LAL_Context,
+              LSP.Types.To_UTF_8_String (Self.URI_To_File (URI)),
+              Charset => Self.Get_Charset);
+
+         Name : constant Libadalang.Analysis.Name :=
+           Laltools.Common.Get_Node_As_Name (Unit.Root.Lookup (Loc));
+
+         Def_Name : constant Libadalang.Analysis.Defining_Name :=
+           Laltools.Common.Get_Name_As_Defining (Name);
+      begin
+         if not Def_Name.Is_Null then
+            Callback (URI, Def_Name, Stop);
+         end if;
+      end Adapter;
+
    begin
-      Self.Source_Files.Get_Any_Symbol_Completion (Prefix, Callback);
+      Self.Source_Files.Get_Any_Symbol_Completion (Prefix, Adapter'Access);
    end Get_Any_Symbol_Completion;
 
    -----------------

source/ada/lsp-ada_file_sets.adb

@@ -160,7 +160,7 @@ package body LSP.Ada_File_Sets is
       Prefix   : VSS.Strings.Virtual_String;
       Callback : not null access procedure
         (URI  : LSP.Messages.DocumentUri;
-         Name : Libadalang.Analysis.Defining_Name;
+         Loc  : Langkit_Support.Slocs.Source_Location;
          Stop : in out Boolean))
    is
       Stop   : Boolean := False;
@@ -176,7 +176,7 @@ package body LSP.Ada_File_Sets is
             exit Each_Prefix when not Value.Starts_With (Prefix);
 
             for Item of Self.All_Symbols (Cursor) loop
-               Callback (Item.URI, Item.Name, Stop);
+               Callback (Item.URI, Item.Loc, Stop);
                exit Each_Prefix when Stop;
             end loop;
 
@@ -258,8 +258,17 @@ package body LSP.Ada_File_Sets is
 
       while It.Next (Node) loop
          declare
+            Token : constant Libadalang.Common.Token_Reference :=
+              Node.Token_End;
+
+            Sloc_Range : constant Langkit_Support.Slocs.Source_Location_Range
+              := Libadalang.Common.Sloc_Range (Libadalang.Common.Data (Token));
+
+            Start_Sloc : constant Langkit_Support.Slocs.Source_Location :=
+              Langkit_Support.Slocs.Start_Sloc (Sloc_Range);
+
             Text : constant Wide_Wide_String :=
-              Libadalang.Common.Text (Node.Token_End);
+              Libadalang.Common.Text (Token);
 
             Canonical : constant Symbolization_Result :=
               Libadalang.Sources.Canonicalize (Text);
@@ -274,7 +283,7 @@ package body LSP.Ada_File_Sets is
                   Cursor,
                   Inserted);
 
-               Self.All_Symbols (Cursor).Append ((URI, Node.As_Defining_Name));
+               Self.All_Symbols (Cursor).Append ((URI, Start_Sloc));
             end if;
          end;
       end loop;

source/ada/lsp-ada_file_sets.ads

@@ -25,6 +25,7 @@ with Ada.Containers.Vectors;
 with GNATCOLL.VFS;
 
 with Libadalang.Analysis;
+with Langkit_Support.Slocs;
 
 with VSS.Strings;
 
@@ -68,7 +69,7 @@ package LSP.Ada_File_Sets is
       Prefix   : VSS.Strings.Virtual_String;
       Callback : not null access procedure
         (URI  : LSP.Messages.DocumentUri;
-         Name : Libadalang.Analysis.Defining_Name;
+         Loc  : Langkit_Support.Slocs.Source_Location;
          Stop : in out Boolean));
    --  Find symbols starting with given Prefix in all files of the set and
    --  call Callback for each. Name could contain a stale reference if the File
@@ -77,7 +78,7 @@ package LSP.Ada_File_Sets is
 private
    type Name_Information is record
       URI  : LSP.Messages.DocumentUri;
-      Name : Libadalang.Analysis.Defining_Name;
+      Loc  : Langkit_Support.Slocs.Source_Location;
    end record;
 
    package Name_Vectors is new Ada.Containers.Vectors