[gnome-games] directory: Add async version of foreach

[Adrien Plazas <aplazas src gnome org>]

commit 3c97991f7ba89f38a540e022c2dcd09c8da2efb4
Author: theawless <theawless gmail com>
Date:   Tue Jun 19 23:25:37 2018 +0530

    directory: Add async version of foreach
    
    This adds the possibility of walking through files of a directory
    asynchronously.
    
    https://gitlab.gnome.org/GNOME/gnome-games/issues/11

 src/utils/directory.vala | 13 +++++++++++++
 1 file changed, 13 insertions(+)
---
diff --git a/src/utils/directory.vala b/src/utils/directory.vala
index 66a0cae..053d0ab 100644
--- a/src/utils/directory.vala
+++ b/src/utils/directory.vala
@@ -15,4 +15,17 @@ public class Games.Directory : Object {
                        if (file_info_test (file_info))
                                return;
        }
+
+       public async void @foreach_async (string attributes, FileInfoTest file_info_test) throws Error {
+               var enumerator = yield file.enumerate_children_async (attributes, FileQueryInfoFlags.NONE);
+               while (true) {
+                       var file_infos = yield enumerator.next_files_async (25);
+                       if (file_infos == null || file_infos.length () == 0)
+                               break;
+
+                       foreach (var file_info in file_infos)
+                               if (file_info_test (file_info))
+                                       return;
+               }
+       }
 }