Export bdd_implies to the Python interface, and test it.

* wrap/python/buddy.i (bdd_implies): New function.
* wrap/python/tests/implies.py: New file.
* wrap/python/tests/Makefile.am: Add it.

wrap/python/buddy.i

@@ -164,6 +164,7 @@ bdd bdd_xor(const bdd &l, const bdd &r);
 bdd bdd_imp(const bdd &l, const bdd &r);
 bdd bdd_biimp(const bdd &l, const bdd &r);
 bdd bdd_setxor(const bdd &l, const bdd &r);
+int bdd_implies(const bdd &l, const bdd &r);
 bdd bdd_ite(const bdd &f, const bdd &g, const bdd &h);
 bdd bdd_exist(const bdd &r, const bdd &var);
 bdd bdd_existcomp(const bdd &r, const bdd &var);

wrap/python/tests/Makefile.am

@@ -31,11 +31,12 @@ check_SCRIPTS = run
 
 TESTS = \
   alarm.py \
-  ltlsimple.py \
-  ltlparse.py \
   bddnqueen.py \
-  ltl2tgba.test \
+  implies.py \
   interdep.py \
+  ltl2tgba.test \
+  ltlparse.py \
+  ltlsimple.py \
   minato.py \
   modgray.py \
   optionmap.py \

wrap/python/tests/implies.py

+# -*- mode: python; coding: utf-8 -*-
+# Copyright (C) 2012 Laboratoire de Recherche et Développement
+# de l'EPITA.
+#
+# This file is part of Spot, a model checking library.
+#
+# Spot is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# Spot is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+# License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Spot; see the file COPYING.  If not, write to the Free
+# Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+# 02111-1307, USA.
+
+import sys
+from buddy import *
+
+bdd_init(10000, 10000)
+bdd_setvarnum(5)
+
+V = [bdd_ithvar(i) for i in range(5)]
+
+a =  V[0] & V[1] & -V[2]
+b =  V[0] & V[1] & -V[2] & -V[3]
+c = -V[0] & V[1] & -V[2] & -V[3]
+d =         V[1] & -V[2]
+e =         V[1] &  V[2] & -V[3] & V[4]
+f =  V[0]                & -V[3] & V[4]
+g = -V[0] | V[1]
+
+assert(bdd_implies(b,a))
+assert(not bdd_implies(a,b))
+assert(not bdd_implies(c,a))
+assert(bdd_implies(a,d))
+assert(bdd_implies(b,d))
+assert(bdd_implies(c,d))
+assert(bdd_implies(d,d))
+assert(not bdd_implies(e,d))
+assert(not bdd_implies(d,e))
+assert(not bdd_implies(f,e))
+assert(not bdd_implies(e,f))
+assert(bdd_implies(bddfalse,f))
+assert(not bdd_implies(bddtrue,f))
+assert(bdd_implies(f,bddtrue))
+assert(not bdd_implies(f,bddfalse))
+assert(bdd_implies(a,g))
+
+a = (-V[2] & (-V[1] | V[0])) | (-V[0] & V[1] & V[2])
+b = V[1] | -V[2]
+assert(bdd_implies(a,b))
+
+# Cleanup all BDD variables before calling bdd_done(), otherwise
+# bdd_delref will be called after bdd_done() and this is unsafe in
+# optimized builds.
+V = a = b = c = d = e = f = g = 0;
+bdd_done()