Add a new length_boolone() function to fix an assert in randpsl.

* src/ltlvisit/length.hh (length_boolone): New function.
* src/ltlvisit/length.cc (length_boolone): Implement it using...
(length_boolone_visitor): ... this new visitor.
* src/ltltest/randltl.cc: Use length_boolone() to check the result
of the random generator, and ignore any formula larger (in
length()) than opt_f.  This fix a bug where the random formula
generator would sometime produce formula larger than requested,
because of the trivial rewriting of {f}[]->e as e|!f.
* src/ltltest/length.cc: Add option -b to call length_boolone().
* src/ltltest/length.test: Test length_boolone().

src/ltlvisit/length.cc

@@ -1,4 +1,4 @@
-// Copyright (C) 2010 Laboratoire de Recherche et Développement de
+// Copyright (C) 2010, 2012 Laboratoire de Recherche et Développement de
 // l'Epita (LRDE).
 // Copyright (C) 2004, 2005  Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
@@ -24,6 +24,7 @@
 #include "length.hh"
 #include "ltlvisit/postfix.hh"
 #include "ltlast/multop.hh"
+#include "ltlast/unop.hh"
 
 namespace spot
 {
@@ -65,6 +66,38 @@ namespace spot
       protected:
 	int result_; // size of the formula
       };
+
+      class length_boolone_visitor: public length_visitor
+      {
+
+	virtual void
+	visit(unop* uo)
+	{
+	  ++result_;
+	  // Boolean formula have length one.
+	  if (!uo->is_boolean())
+	    uo->child()->accept(*this);
+	}
+
+	virtual void
+	visit(multop* mo)
+	{
+	  // Boolean formula have length one.
+	  if (mo->is_boolean())
+	    {
+	      ++result_;
+	      return;
+	    }
+
+	  unsigned s = mo->size();
+	  for (unsigned i = 0; i < s; ++i)
+	    mo->nth(i)->accept(*this);
+	  // "a & b & c" should count for 5, even though it is
+	  // stored as And(a,b,c).
+	  result_ += s - 1;
+	}
+
+      };
     }
 
     int
@@ -75,5 +108,13 @@ namespace spot
       return v.result();
     }
 
+    int
+    length_boolone(const formula* f)
+    {
+      length_boolone_visitor v;
+      const_cast<formula*>(f)->accept(v);
+      return v.result();
+    }
+
   }
 }

src/ltlvisit/length.hh

@@ -33,13 +33,23 @@ namespace spot
     /// \brief Compute the length of a formula.
     /// \ingroup ltl_misc
     ///
-    /// The length of a formula is the number of atomic properties,
+    /// The length of a formula is the number of atomic propositions,
     /// constants, and operators (logical and temporal) occurring in
     /// 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
+    /// count for n-1; for instance <code>a | b | c</code> has length
+    /// 5, even if there is only as single <code>|</code> node
     /// internally.
+    ///
+    /// If squash_boolean is set, all Boolean formulae are assumed
+    /// to have length one.
     int length(const formula* f);
+
+    /// \brief Compute the length of a formula, squashing Boolean formulae
+    /// \ingroup ltl_misc
+    ///
+    /// This is similar to spot::ltl::length(), except all Boolean
+    /// formulae are assumed to have length one.
+    int length_boolone(const formula* f);
   }
 }