From 11d3528406bfcbb3f97780d4b2af571c0b3f6299 Mon Sep 17 00:00:00 2001
From: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
Date: Sun, 15 Jun 2014 19:09:46 +0200
Subject: [PATCH] When parsing moves, use illegal moves to disambiguate.

---
 Board.pm | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Board.pm b/Board.pm
index b925a38..1838f7d 100644
--- a/Board.pm
+++ b/Board.pm
@@ -194,6 +194,14 @@ sub parse_pretty_move {
 			next if (defined($from_col) && $from_col != $col);
 			next if ($board->[$row][$col] ne $piece);
 			next if (!$board->can_reach($piece, $row, $col, $to_row, $to_col));
+
+			# See if doing this move would put us in check
+			# (yes, there are clients that expect us to do this).
+			my $check = $board->make_move($row, $col, $to_row, $to_col, $promo)->in_check();
+			next if ($check eq 'both' ||
+			         ($toplay eq 'W' && $check eq 'white') ||
+			         ($toplay eq 'B' && $check eq 'black'));
+
 			push @squares, [ $row, $col ];
 		}
 	}
-- 
2.39.2