Add with-clause for invisible completion items

We now append the right 'als-auto-import' command to
invisible completion items, when the 'insertWithClauses' setting
is enabled.

This allows client that support executing completionItem commands
to execute the attached command in order to add the missing with-clause,
appending the qualifier if not already specified.

Automatic tests for both cases (i.e: with and without an already specified
qualifier) have been added.

For eng/ide/ada_language_server#1159

Author: AnthonyLeonardoGracio

README.md

@@ -28,7 +28,7 @@ The Ada Language Server now also supports the GPR language, via the
 such as navigation, outline and tooltips for GPR files. When this switch is
 present, the server will only support GPR files. To support both GPR and
 Ada/SPARK, you'll need to launch two instances of the server.
-You can refer to the [Supported LSP Server Requests](#supported-lsp-server-requests) 
+You can refer to the [Supported LSP Server Requests](#supported-lsp-server-requests)
 section for more information.
 
 We also provide [Visual Studio Code](https://code.visualstudio.com/)

doc/settings.md

@@ -62,6 +62,8 @@ Ada Language Server understands these settings:
 * [renameInComments](#renameincomments)
 * [namedNotationThreshold](#namednotationthreshold)
 * [foldComments](#foldcomments)
+* [useCompletionSnippets](#usecompletionsnippets)
+* [insertWithClauses](#insertwithclauses)
 * [followSymlinks](#followsymlinks)
 * [documentationStyle](#documentationstyle)
 * [onTypeFormatting.indentOnly](#ontypeformattingindentonly)
@@ -172,6 +174,15 @@ The value is a boolean.
     'useCompletionSnippets': true
 ```
 
+## insertWithClauses
+
+Whether we should automatically insert missing with-clauses when
+accepting completion for invisible symbols.
+
+```javascript
+    'insertWithClauses': true
+```
+
 ## displayMethodAncestryOnNavigation
 
 This setting controls the policy for displaying overriding and overridden

integration/vscode/ada/package.json

@@ -391,6 +391,12 @@
                         "default": false,
                         "description": "Enable snippets in completion results (e.g. subprogram calls)."
                     },
+                    "ada.insertWithClauses": {
+                        "scope": "window",
+                        "type": "boolean",
+                        "default": false,
+                        "description": "Enable insertion of missing with-clauses when accepting completion for invisible symbols."
+                    },
                     "ada.renameInComments": {
                         "scope": "window",
                         "type": "boolean",

source/ada/lsp-ada_configurations.adb

@@ -277,6 +277,11 @@ package body LSP.Ada_Configurations is
          then
             Self.Use_Completion_Snippets := JSON (Index).Boolean_Value;
 
+         elsif Name = "insertWithClauses"
+           and then JSON (Index).Kind = Boolean_Value
+         then
+            Self.Insert_With_Clauses := JSON (Index).Boolean_Value;
+
          elsif Name = "logThreshold"
            and then JSON (Index).Kind = Number_Value
            and then JSON (Index).Number_Value.Kind = JSON_Integer

source/ada/lsp-ada_configurations.ads

@@ -78,6 +78,11 @@ package LSP.Ada_Configurations is
    --  True if we should use snippets for completion (e.g:
    --  subprogram calls).
 
+   function Insert_With_Clauses
+     (Self : Configuration'Class) return Boolean;
+   --  True if completion is allowed to insert automatically with-clauses for
+   --  invisible symbols.
+
    function Indent_Only (Self : Configuration'Class) return Boolean;
 
    function Follow_Symlinks (Self : Configuration'Class) return Boolean;
@@ -130,6 +135,7 @@ private
       Use_Completion_Snippets  : Boolean := True;
       Indent_Only              : Boolean := True;
       Follow_Symlinks          : Boolean := True;
+      Insert_With_Clauses      : Boolean := True;
 
       Documentation_Style      : GNATdoc.Comments.Options.Documentation_Style
         := GNATdoc.Comments.Options.GNAT;
@@ -169,8 +175,14 @@ private
       (Self.Indexing_Enabled);
 
    function Use_Completion_Snippets
-     (Self : Configuration'Class) return Boolean is
-       (Self.Use_Completion_Snippets);
+     (Self : Configuration'Class) return Boolean
+   is
+     (Self.Use_Completion_Snippets);
+
+   function Insert_With_Clauses
+     (Self : Configuration'Class) return Boolean
+   is
+     (Self.Insert_With_Clauses);
 
    function Follow_Symlinks (Self : Configuration'Class) return Boolean is
       (Self.Follow_Symlinks);

source/ada/lsp-ada_documents.adb

@@ -43,6 +43,7 @@ with LSP.Ada_Contexts;
 with LSP.Ada_Documentation;
 with LSP.Ada_Documents.LAL_Diagnostics;
 with LSP.Ada_Handlers.Locations;
+with LSP.Ada_Handlers.Refactor.Auto_Import;
 with LSP.Ada_Id_Iterators;
 with LSP.Enumerations;
 with LSP.Formatters.File_Names;
@@ -131,6 +132,10 @@ package body LSP.Ada_Documents is
       --  Return a suitable sortText according to the completion item's
       --  visibility and position in the completion list.
 
+      procedure Append_Auto_Import_Command;
+      --  Append the needed command to add the missing with-clause/qualifier
+      --  when accepting an invisible completion item.
+
       -------------------
       -- Get_Sort_Text --
       -------------------
@@ -155,6 +160,57 @@ package body LSP.Ada_Documents is
          end return;
       end Get_Sort_Text;
 
+      --------------------------------
+      -- Append_Auto_Import_Command --
+      --------------------------------
+
+      procedure Append_Auto_Import_Command is
+         use LSP.Ada_Handlers.Refactor;
+
+         Auto_Import_Command : Auto_Import.Command;
+         --  The auto-import command.
+
+         Is_Dotted_Name     : constant Boolean :=
+           Node.Kind in Libadalang.Common.Ada_Dotted_Name_Range
+           or else
+             (not Node.Parent.Is_Null and then
+              Node.Parent.Kind
+              in Libadalang.Common.Ada_Dotted_Name_Range);
+         --  Check if we are completing a dotted name. We want to prepend the
+         --  right qualifier only if it's not the case.
+
+         Missing_Unit_Name  : VSS.Strings.Virtual_String :=
+           VSS.Strings.Conversions.To_Virtual_String
+             (Langkit_Support.Text.To_UTF8
+                (BD.P_Enclosing_Compilation_Unit.P_Decl.
+                       P_Fully_Qualified_Name));
+         --  Get the missing unit name.
+
+         Missing_Qualifier  : VSS.Strings.Virtual_String :=
+           (if not Is_Dotted_Name then
+               Missing_Unit_Name
+            else
+               VSS.Strings.Empty_Virtual_String);
+         --  The missing qualifier. We should not add any qualifier if it's
+         --  already present (i.e: when completing a dotted name).
+      begin
+         Auto_Import_Command.Initialize
+           (Context     => Context,
+            Where       =>
+              ((uri => Document.URI),
+               Document.To_LSP_Position (Sloc)),
+            With_Clause => Missing_Unit_Name,
+            Prefix      => Missing_Qualifier);
+
+         Item.command :=
+           (Is_Set => True,
+            Value  =>
+              (title     => <>,
+               command   => VSS.Strings.Conversions.
+                 To_Virtual_String (Auto_Import.Command'External_Tag),
+               arguments => Auto_Import_Command.Write_Command_Args));
+      end Append_Auto_Import_Command;
+
    begin
       Item.label := Label;
       Item.kind := (True, To_Completion_Kind (LSP.Utils.Get_Decl_Kind (BD)));
@@ -163,6 +219,12 @@ package body LSP.Ada_Documents is
          Item.insertText := Label;
          Item.label.Append (" (invisible)");
          Item.filterText := Label;
+
+         --  If the corresponding setting is enabled, append a command to
+         --  insert the missing with-clause/qualifier.
+         if Handler.Get_Configuration.Insert_With_Clauses then
+            Append_Auto_Import_Command;
+         end if;
       end if;
 
       Item.sortText := Get_Sort_Text (Label);

source/ada/lsp-ada_handlers-refactor-auto_import.adb

@@ -170,7 +170,7 @@ package body LSP.Ada_Handlers.Refactor.Auto_Import is
                            (title     => <>,
                             command   => VSS.Strings.Conversions.
                               To_Virtual_String (Command'External_Tag),
-                            arguments => Self.Write_Command)),
+                            arguments => Self.Write_Command_Args)),
          data        => <>);
 
       Commands_Vector.Append
@@ -232,7 +232,7 @@ package body LSP.Ada_Handlers.Refactor.Auto_Import is
    -- Write_Command --
    -------------------
 
-   function Write_Command
+   function Write_Command_Args
      (Self : Command) return LSP.Structures.LSPAny_Vector
    is
       use VSS.JSON.Streams;
@@ -267,6 +267,6 @@ package body LSP.Ada_Handlers.Refactor.Auto_Import is
       Result.Append (JSON_Stream_Element'(Kind => End_Array));
 
       return Result;
-   end Write_Command;
+   end Write_Command_Args;
 
 end LSP.Ada_Handlers.Refactor.Auto_Import;

source/ada/lsp-ada_handlers-refactor-auto_import.ads

@@ -48,6 +48,12 @@ package LSP.Ada_Handlers.Refactor.Auto_Import is
    --  Initializes Command based on Suggestion and appends it to
    --  Commands_Vector.
 
+   function Write_Command_Args
+     (Self : Command) return LSP.Structures.LSPAny_Vector;
+   --  Write the given command's arguments as LPS any vector.
+   --  These arguments are then passed to the server by the LSP client when
+   --  executing the command via the executeCommand LSP request.
+
 private
 
    type Command is new LSP.Ada_Handlers.Refactor.Command with record
@@ -69,9 +75,6 @@ private
      return LSP.Server_Jobs.Job_Priority
        is (LSP.Server_Jobs.Low);
 
-   function Write_Command
-     (Self : Command) return LSP.Structures.LSPAny_Vector;
-
    function Command_To_Refactoring_Edits
      (Self     : Command;
       Context  : LSP.Ada_Contexts.Context;

source/server/lsp-text_documents-langkit_documents.adb

@@ -103,6 +103,19 @@ package body LSP.Text_Documents.Langkit_Documents is
           character => To_LSP_Column
             (End_Line_Text, A_Range.End_Column, False)));
 
+   ---------------------
+   -- To_LSP_Position --
+   ---------------------
+
+   function To_LSP_Position
+     (Self    : Langkit_Text_Document'Class;
+      Sloc : Langkit_Support.Slocs.Source_Location)
+      return LSP.Structures.Position
+   is
+     (line => To_LSP_Line (Sloc.Line),
+      character => To_LSP_Column
+        (Self.Line (Sloc.Line), Sloc.Column, False));
+
    -------------------
    -- To_LSP_Column --
    -------------------

source/server/lsp-text_documents-langkit_documents.ads

@@ -70,6 +70,12 @@ package LSP.Text_Documents.Langkit_Documents is
       return LSP.Structures.A_Range;
    --  Convert Langkit Source_Location_Range to LSP's A_Range
 
+   function To_LSP_Position
+     (Self : Langkit_Text_Document'Class;
+      Sloc : Langkit_Support.Slocs.Source_Location)
+      return LSP.Structures.Position;
+   --  Convert a Langkit Source_Location to the corresponding LSP position.
+
 private
 
    type Langkit_Text_Document is abstract new Text_Document with null record;