[gnome-builder] vala-pack: create ValaIndex lazily

[Christian Hergert <chergert src gnome org>]

commit 71f59b6b708f15150bff8831ba1cd6b84edf64b3
Author: Christian Hergert <chergert redhat com>
Date:   Wed Jan 24 22:46:01 2018 -0800

    vala-pack: create ValaIndex lazily
    
    We don't want to do this work until something has requested
    access to vala code-insight. Otherwise, the ValaCodeContext
    creates some ~30,000 structures which are just unnecessary.
    
    It saves some 20mb of resident upon opening a project.

 src/plugins/vala-pack/ide-vala-service.vala | 33 +++++++++++++++++------------
 1 file changed, 19 insertions(+), 14 deletions(-)
---
diff --git a/src/plugins/vala-pack/ide-vala-service.vala b/src/plugins/vala-pack/ide-vala-service.vala
index 40b528f90..1ed406d61 100644
--- a/src/plugins/vala-pack/ide-vala-service.vala
+++ b/src/plugins/vala-pack/ide-vala-service.vala
@@ -26,29 +26,34 @@ namespace Ide
        {
                Ide.ValaIndex _index;
 
-               public ValaIndex index {
-                       get { return this._index; }
-               }
-
                public unowned string get_name () {
                        return typeof (Ide.ValaService).name ();
                }
 
-               public void start () {
-                       this._index = new Ide.ValaIndex (this.get_context ());
+               public ValaIndex index {
+                       get {
+                               if (this._index == null) {
+                                       this._index = new Ide.ValaIndex (this.get_context ());
 
-                       Ide.ThreadPool.push (Ide.ThreadPoolKind.INDEXER, () => {
-                               Ide.Vcs vcs = this.get_context ().get_vcs ();
-                               var files = new ArrayList<GLib.File> ();
+                                       Ide.ThreadPool.push (Ide.ThreadPoolKind.INDEXER, () => {
+                                               Ide.Vcs vcs = this.get_context ().get_vcs ();
+                                               var files = new ArrayList<GLib.File> ();
 
-                               load_directory (vcs.get_working_directory (), null, files);
+                                               load_directory (vcs.get_working_directory (), null, files);
 
-                               if (files.size > 0) {
-                                       this._index.add_files.begin (files, null, () => {
-                                               debug ("Vala files registered");
+                                               if (files.size > 0) {
+                                                       this._index.add_files.begin (files, null, () => {
+                                                               debug ("Vala files registered");
+                                                       });
+                                               }
                                        });
                                }
-                       });
+
+                               return this._index;
+                       }
+               }
+
+               public void start () {
                }
 
                public void stop () {