[iagno] Remove can_undo().

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 16da7a83939ddea8e4148a29b3f8fc82981d50f6
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Wed Sep 24 07:55:01 2014 +0200

    Remove can_undo().
    
    https://bugzilla.gnome.org/show_bug.cgi?id=736934

 src/game.vala       |    8 +-------
 src/iagno.vala      |    6 +++---
 src/test-iagno.vala |   18 +++++++++---------
 3 files changed, 13 insertions(+), 19 deletions(-)
---
diff --git a/src/game.vala b/src/game.vala
index 5cf4fb6..41e0d96 100644
--- a/src/game.vala
+++ b/src/game.vala
@@ -28,7 +28,7 @@ public class Game : Object
     /* Color to move next; Dark always plays first;
      * should be dark if number_of_moves % 2 == 0 */
     public Player current_color { get; private set; default = Player.DARK; }
-    private int number_of_moves = 0;
+    public int number_of_moves { get; private set; default = 0; }
 
     /* Indicate that a player should move */
     public signal void move ();
@@ -313,12 +313,6 @@ public class Game : Object
     * * Undo
     \*/
 
-    public bool can_undo (int count = 1)
-        requires (count == 1 || count == 2)
-    {
-        return number_of_moves >= count;
-    }
-
     public void undo (int count = 1)
         requires (count == 1 || count == 2)
         requires (number_of_moves >= count)
diff --git a/src/iagno.vala b/src/iagno.vala
index a02652b..758c70c 100644
--- a/src/iagno.vala
+++ b/src/iagno.vala
@@ -249,12 +249,12 @@ public class Iagno : Gtk.Application
 
         var undo_action = (SimpleAction) lookup_action ("undo-move");
         if (player_one == Player.DARK || computer == null)
-            undo_action.set_enabled (game.can_undo (1));
+            undo_action.set_enabled (game.number_of_moves >= 1);
         else
-            undo_action.set_enabled (game.can_undo (2));
+            undo_action.set_enabled (game.number_of_moves >= 2);
 
         var new_game_action = (SimpleAction) lookup_action ("new-game");
-        new_game_action.set_enabled (game.can_undo (1));
+        new_game_action.set_enabled (game.number_of_moves >= 1);
 
         /* Translators: this is a 2 digit representation of the current score. */
         dark_score_label.set_markup ("<span font_weight='bold'>"+(_("%.2d").printf 
(game.n_dark_tiles))+"</span>");
diff --git a/src/test-iagno.vala b/src/test-iagno.vala
index 95e08b0..73fc4fa 100644
--- a/src/test-iagno.vala
+++ b/src/test-iagno.vala
@@ -31,31 +31,31 @@ public class TestIagno : Object
                           " L L L L L L L L",
                           " L L L L L L L L"};
         Game game = new Game.from_strings (board, Player.DARK);
+        assert (game.number_of_moves == 0);
         assert (game.place_tile (7, 2) > 0);
+        assert (game.number_of_moves == 1);
         assert (!game.can_move (Player.LIGHT));
-        assert (game.can_undo ());
         game.pass ();
-        assert (game.can_undo ());
+        assert (game.number_of_moves == 2);
         game.undo (2);
+        assert (game.number_of_moves == 0);
         assert (game.to_string ().strip () == string.joinv ("\n", board).strip ());
         assert (game.place_tile (7, 2) > 0);
+        assert (game.number_of_moves == 1);
         assert (!game.can_move (Player.LIGHT));
-        assert (game.can_undo ());
         game.undo (1);
+        assert (game.number_of_moves == 0);
         assert (game.to_string ().strip () == string.joinv ("\n", board).strip ());
     }
 
     private static void test_undo_at_start ()
     {
         Game game = new Game ();
-        assert (!game.can_undo (1));
-        assert (!game.can_undo (2));
+        assert (game.number_of_moves == 0);
         game.place_tile (2, 3);
-        assert (game.can_undo (1));
-        assert (!game.can_undo (2));
+        assert (game.number_of_moves == 1);
         game.place_tile (2, 2);
-        assert (game.can_undo (1));
-        assert (game.can_undo (2));
+        assert (game.number_of_moves == 2);
     }
 
     private static void test_current_color_after_pass ()