[grilo-plugins] thegamesdb: Fix cover not found when there's no back cover

[Bastien Nocera <hadess src gnome org>]

commit 363c0e7727b9448cfd4f4661115c3828e9176832
Author: Bastien Nocera <hadess hadess net>
Date:   Sun May 29 00:35:02 2016 +0200

    thegamesdb: Fix cover not found when there's no back cover
    
    As in the test case included ("Astérix" on the Game Gear).

 src/lua-factory/sources/grl-thegamesdb.lua |   12 +++++++++---
 tests/games/test_games.c                   |    6 ++++++
 2 files changed, 15 insertions(+), 3 deletions(-)
---
diff --git a/src/lua-factory/sources/grl-thegamesdb.lua b/src/lua-factory/sources/grl-thegamesdb.lua
index 9957a74..045851f 100644
--- a/src/lua-factory/sources/grl-thegamesdb.lua
+++ b/src/lua-factory/sources/grl-thegamesdb.lua
@@ -211,9 +211,15 @@ function fetch_game_cb(results)
 
     if game.Images and
        game.Images.boxart then
-      for index, boxart in pairs(game.Images.boxart) do
-        if boxart.side == 'front' then
-          media.thumbnail = base_url .. boxart.xml
+      -- Handle having a single boxart image
+      if game.Images.boxart.side and
+         game.Images.boxart.side == 'front' then
+        media.thumbnail = base_url .. game.Images.boxart.xml
+      else
+        for index, boxart in pairs(game.Images.boxart) do
+          if boxart.side == 'front' then
+            media.thumbnail = base_url .. boxart.xml
+          end
         end
       end
     end
diff --git a/tests/games/test_games.c b/tests/games/test_games.c
index efdad2c..e02d354 100644
--- a/tests/games/test_games.c
+++ b/tests/games/test_games.c
@@ -177,6 +177,12 @@ test_resolve_thumbnails_found (void)
                                 0,
                                 "http://thegamesdb.net/banners/boxart/original/front/3016-1.jpg";);
 
+  test_resolve_thumbnail_found (source, keys, options,
+                                "Astérix",
+                                "",
+                                0,
+                                "http://thegamesdb.net/banners/boxart/original/front/11837-1.jpg";);
+
   g_list_free (keys);
   g_object_unref (options);
 }