Fix computation of length of LTL formulas.

* src/ltlvisit/length.cc: Fix computation for ltl::multop
operator. "a&b&c" was reported with length 3, ignoring the
"&" operators, because of a typo.
* src/ltlvisit/length.hh: Fix description to correctly
reflect this change intended since 2010-01-22.
* src/ltltest/length.test, src/ltltest/length.cc: New files.
* src/ltltest/Makefile.am: Add them.

ChangeLog

+2012-01-05  Alexandre Duret-Lutz  <adl@lrde.epita.fr>
+
+	Fix computation of length of LTL formulas.
+
+	* src/ltlvisit/length.cc: Fix computation for ltl::multop
+	operator. "a&b&c" was reported with length 3, ignoring the
+	"&" operators, because of a typo.
+	* src/ltlvisit/length.hh: Fix description to correctly
+	reflect this change intended since 2010-01-22.
+	* src/ltltest/length.test, src/ltltest/length.cc: New files.
+	* src/ltltest/Makefile.am: Add them.
+
 2011-12-18  Alexandre Duret-Lutz  <adl@lrde.epita.fr>
 
 	* configure.ac, NEWS: Bump version to 0.8.1a.

NEWS

 New in spot 0.8.1a:
 
-  * Nothing yet.
+  * Bug fixes:
+    - spot::ltl::length() forgot to count the '&' and '|' operators
+      in an LTL formula.
 
 New in spot 0.8.1:
 

src/ltltest/Makefile.am

-## Copyright (C) 2009, 2010, 2011 Laboratoire de Recherche et Dveloppement
-## de l'Epita (LRDE).
+## Copyright (C) 2009, 2010, 2011, 2012 Laboratoire de Recherche et
+## Dveloppement de l'Epita (LRDE).
 ## Copyright (C) 2003, 2004, 2005, 2006 Laboratoire d'Informatique de
 ## Paris 6 (LIP6), dpartement Systmes Rpartis Coopratifs (SRC),
 ## Universit Pierre et Marie Curie.
@@ -29,6 +29,7 @@ check_SCRIPTS = defs
 # Keep this sorted alphabetically.
 check_PROGRAMS = \
   equals \
+  length \
   ltl2dot \
   ltl2text \
   lunabbrev \
@@ -48,6 +49,7 @@ noinst_PROGRAMS = \
 
 equals_SOURCES = equals.cc
 genltl_SOURCES = genltl.cc
+length_SOURCES = length.cc
 ltl2dot_SOURCES = readltl.cc
 ltl2dot_CPPFLAGS = $(AM_CPPFLAGS) -DDOTTY
 ltl2text_SOURCES = readltl.cc
@@ -77,6 +79,7 @@ EXTRA_DIST = $(TESTS)
 TESTS = \
   parse.test \
   parseerr.test \
+  length.test \
   equals.test \
   tostring.test \
   lunabbrev.test \

src/ltltest/length.cc

+// Copyright (C) 2012 Laboratoire de Recherche et Developement de
+// l'Epita (LRDE).
+//
+// 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.
+
+#include <iostream>
+#include <cassert>
+#include <cstdlib>
+#include "ltlparse/public.hh"
+#include "ltlvisit/length.hh"
+#include "ltlast/allnodes.hh"
+
+void
+syntax(char *prog)
+{
+  std::cerr << prog << " formula" << std::endl;
+  exit(2);
+}
+
+int
+main(int argc, char **argv)
+{
+  if (argc != 2)
+    syntax(argv[0]);
+
+  spot::ltl::parse_error_list p1;
+  spot::ltl::formula* f1 = spot::ltl::parse(argv[1], p1);
+
+  if (spot::ltl::format_parse_errors(std::cerr, argv[1], p1))
+    return 2;
+
+  std::cout << spot::ltl::length(f1) << std::endl;
+
+  f1->destroy();
+  assert(spot::ltl::atomic_prop::instance_count() == 0);
+  assert(spot::ltl::unop::instance_count() == 0);
+  assert(spot::ltl::binop::instance_count() == 0);
+  assert(spot::ltl::multop::instance_count() == 0);
+  return 0;
+}

src/ltltest/length.test

+#! /bin/sh
+# Copyright (C) 2012 Laboratoire de Recherche et Developpement
+# de l'Epita (LRDE).
+#
+# 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.
+
+
+. ./defs || exit 1
+
+set -e
+
+test `run 0 ../length 'a U Xc'` = 4
+test `run 0 ../length 'a&b&c'` = 5
+test `run 0 ../length 'a|b|c'` = 5

src/ltlvisit/length.cc

@@ -53,7 +53,7 @@ namespace spot
 	    mo->nth(i)->accept(*this);
 	  // "a & b & c" should count for 5, even though it is
 	  // stored as And(a,b,c).
-	  mo += s - 1;
+	  result_ += s - 1;
 	}
 
 	virtual void

src/ltlvisit/length.hh

+// Copyright (C) 2012 Laboratoire de Recherche et Developement de
+// l'Epita (LRDE).
 // Copyright (C) 2004, 2005  Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
@@ -33,10 +35,10 @@ namespace spot
     ///
     /// The length of a formula is the number of atomic properties,
     /// constants, and operators (logical and temporal) occurring in
-    /// the formula.  spot::ltl::multops count only for 1, even if
-    /// they have more than two operands (e.g. <code>a | b | c</code>
-    /// has length 4, because <code>|</code> is represented once
-    /// internally).
+    /// the formula.  spot::ltl::multop instances with n arguments
+    /// count only n-1; for instance <code>a | b | c</code>
+    /// has length 5, even if there is only as single <code>|</code> node
+    /// internally.
     int length(const formula* f);
   }
 }