testDocument/declaration support

- implements On_Declaration_Request
- add test

See ada_language_server#1225

source/gpr/lsp-gpr_handlers.adb

@@ -341,6 +341,7 @@ package body LSP.GPR_Handlers is
 
       Capabilities.hoverProvider := LSP.Constants.True;
       Capabilities.definitionProvider := LSP.Constants.True;
+      Capabilities.declarationProvider := LSP.Constants.True;
       Capabilities.completionProvider :=
         (Is_Set => True,
          Value  => (triggerCharacters => [" "],
@@ -431,6 +432,55 @@ package body LSP.GPR_Handlers is
       Self.Sender.On_Completion_Resolve_Response (Id, Response);
    end On_Completion_Resolve_Request;
 
+   ----------------------------
+   -- On_Declaration_Request --
+   ----------------------------
+
+   overriding procedure On_Declaration_Request
+     (Self  : in out Message_Handler;
+      Id    : LSP.Structures.Integer_Or_Virtual_String;
+      Value : LSP.Structures.DeclarationParams)
+   is
+      procedure Fill_Declaration;
+      --  Utility function, appends to Vector the definition if any.
+
+      Response : LSP.Structures.Declaration_Result  (LSP.Structures.Variant_1);
+
+      ----------------------
+      -- Fill_Declaration --
+      ----------------------
+
+      procedure Fill_Declaration is
+         File         : constant LSP.GPR_Files.File_Access :=
+                          LSP.GPR_Files.Parse
+                            (File_Provider => Self'Unchecked_Access,
+                             Path          => Self.To_File
+                               (Value.textDocument.uri));
+
+         Reference : constant Gpr_Parser.Common.Token_Reference :=
+                       LSP.GPR_Files.References.Token_Reference
+                         (File, Value.position);
+
+         Location : LSP.Structures.Location;
+
+         use type Gpr_Parser.Common.Token_Reference;
+
+      begin
+         if Reference /= Gpr_Parser.Common.No_Token then
+            Location.uri :=
+              LSP.GPR_File_Readers.To_URI (Reference.Origin_Filename);
+            Location.a_range := To_Range (Self'Unchecked_Access, Reference);
+            Response.Variant_1.Append (Location);
+         end if;
+
+      end Fill_Declaration;
+
+   begin
+      Fill_Declaration;
+
+      Self.Sender.On_Declaration_Response (Id, Response);
+   end On_Declaration_Request;
+
    ---------------------------
    -- On_Definition_Request --
    ---------------------------

source/gpr/lsp-gpr_handlers.ads

@@ -167,6 +167,11 @@ private
       Id    : LSP.Structures.Integer_Or_Virtual_String;
       Value : LSP.Structures.DefinitionParams);
 
+   overriding procedure On_Declaration_Request
+     (Self  : in out Message_Handler;
+      Id    : LSP.Structures.Integer_Or_Virtual_String;
+      Value : LSP.Structures.DeclarationParams);
+
    -----------------------------------------
    -- LSP.GPR_Documents.Document_Provider --
    -----------------------------------------

testsuite/gpr_lsp/declaration/aggregating.gpr

@@ -0,0 +1,7 @@
+aggregate project GPS_Aggregated is
+
+   for Project_Files use
+     ("ignored.gpr", "navigation.gpr");
+   for Object_Dir use "obj";
+
+end GPS_Aggregated;

testsuite/gpr_lsp/declaration/imported.gpr

@@ -0,0 +1,13 @@
+abstract project Imported is
+   type T is ("0", "1");
+   V := "0";
+   for Exec_Dir use "exe";
+   package Compiler is
+      V := "0";
+      for Switches ("Ada") use ();
+   end Compiler;
+   package Builder is
+   end Builder;
+   package Binder is
+   end Binder;
+end Imported;

testsuite/gpr_lsp/declaration/navigation.gpr

@@ -0,0 +1,23 @@
+with "ignored", "imported";
+project Navigation is
+
+   type T is ("0", "1");
+   V : T := "0";
+   for Source_Dirs use ("src");
+   package Compiler is
+      V := ();
+      for Switches ("Ada") use V;
+      V1 := Navigation.Compiler'Switches ("Ada");
+      V2 := Compiler'Switches ("Ada");
+      V3 := Compiler.V;
+      V4 : Imported.T := Imported.V;
+      V5 := Imported'Exec_Dir;
+      V6 := Imported.Compiler'Switches ("Ada");
+      V7 := Imported.Compiler.V;
+   end Compiler;
+   package Builder renames Imported.Builder;
+   package Binder extends Imported.Binder is
+   end Binder;
+   V8 := V;
+
+end Navigation;

testsuite/gpr_lsp/declaration/prj.gpr

@@ -0,0 +1,7 @@
+aggregate project GPS_Aggregated is
+
+   for Project_Files use
+     ("ignored.gpr", "navigation.gpr");
+   for Object_Dir use "obj";
+
+end GPS_Aggregated;