randaut: add option --acc-type=random

Fixes #71.

* src/bin/randaut.cc: Implement option --acc-type.
* src/tgbaalgos/randomgraph.cc,
src/tgbaalgos/randomgraph.hh (random_acceptance): New function.
* src/tgbatest/randaut.test, wrap/python/tests/randaut.ipynb: Test it.

src/bin/randaut.cc

@@ -26,6 +26,7 @@
 #include <sstream>
 #include <iterator>
 #include "error.h"
+#include "argmatch.h"
 
 #include "common_setup.hh"
 #include "common_range.hh"
@@ -64,12 +65,16 @@ states, 1 to 3 acceptance sets, and three atomic propositions:\n\
 enum {
   OPT_SEED = 1,
   OPT_STATE_ACC,
+  OPT_ACC_TYPE,
 };
 
 static const argp_option options[] =
   {
     /**************************************************/
     { 0, 0, 0, 0, "Generation:", 2 },
+    { "acc-type", OPT_ACC_TYPE, "buchi|random", 0,
+      "use a generalized buchi acceptance condition (default), or a "
+      "random acceptance condition", 0 },
     { "acc-sets", 'A', "RANGE", 0, "number of acceptance sets (0)", 0 },
     { "acc-probability", 'a', "FLOAT", 0,
       "probability that a transition belong to one acceptance set (0.2)", 0 },
@@ -102,6 +107,23 @@ static const struct argp_child children[] =
     { 0, 0, 0, 0 }
   };
 
+enum acc_type { acc_buchi, acc_random };
+
+static char const *const acc_args[] =
+{
+  "buchi", "ba", "gba",
+  "random",
+  0
+};
+static acc_type const acc_types[] =
+{
+  acc_buchi, acc_buchi, acc_buchi,
+  acc_random,
+};
+ARGMATCH_VERIFY(acc_args, acc_types);
+
+
+static acc_type opt_acc = acc_buchi;
 typedef spot::tgba_digraph::graph_t::trans_storage_t tr_t;
 typedef std::set<std::vector<tr_t>> unique_aut_t;
 static spot::ltl::atomic_prop_set aprops;
@@ -171,6 +193,9 @@ parse_opt(int key, char* arg, struct argp_state* as)
       opt_uniq =
         std::unique_ptr<unique_aut_t>(new std::set<std::vector<tr_t>>());
       break;
+    case OPT_ACC_TYPE:
+      opt_acc = XARGMATCH("--acc-type", arg, acc_args, acc_types);
+      break;
     case OPT_SEED:
       opt_seed = to_int(arg);
       opt_seed_str = arg;
@@ -229,9 +254,15 @@ main(int argc, char** argv)
   if (automaton_format == Spin && opt_acc_sets.max > 1)
     error(2, 0, "--spin is incompatible with --acc-sets=%d..%d",
 	  opt_acc_sets.min, opt_acc_sets.max);
+  if (automaton_format == Spin && opt_acc != acc_buchi)
+    error(2, 0,
+	  "--spin implies --acc-type=buchi but a different --acc-type is used");
   if (ba_wanted && opt_acc_sets.min != 1 && opt_acc_sets.max != 1)
     error(2, 0, "--ba is incompatible with --acc-sets=%d..%d",
 	  opt_acc_sets.min, opt_acc_sets.max);
+  if (ba_wanted && opt_acc != acc_buchi)
+    error(2, 0,
+	  "--ba implies --acc-type=buchi but a different --acc-type is used");
 
   try
     {
@@ -263,6 +294,16 @@ main(int argc, char** argv)
 			       accs, opt_acc_prob, 0.5,
 			       opt_deterministic, opt_state_acc);
 
+	  switch (opt_acc)
+	    {
+	    case acc_buchi:
+	      // Random_graph builds a GBA by default
+	      break;
+	    case acc_random:
+	      aut->set_acceptance(accs, spot::random_acceptance(accs));
+	      break;
+	    }
+
 	  if (opt_uniq)
 	    {
 	      auto tmp = spot::canonicalize

src/tgbaalgos/randomgraph.cc

@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2008, 2009, 2010, 2012, 2013, 2014 Laboratoire de
+// Copyright (C) 2008, 2009, 2010, 2012, 2013, 2014, 2015 Laboratoire de
 // Recherche et Développement de l'Epita (LRDE).
 // Copyright (C) 2004, 2005, 2007 Laboratoire d'Informatique de
 // Paris 6 (LIP6), département Systèmes Répartis Coopératifs (SRC),
@@ -241,4 +241,41 @@ namespace spot
     return res;
   }
 
+  acc_cond::acc_code random_acceptance(unsigned n_accs)
+  {
+    // With 0 acceptance sets, we always generate the true acceptance.
+    // (Working with false is somehow pointless, and the formulas we
+    // generate for n_accs>0 are always satisfiable, so it makes sense
+    // that it should be satisfiable for n_accs=0 as well.)
+    if (n_accs == 0)
+      return {};
+
+    acc_cond acc(n_accs);
+    std::vector<acc_cond::acc_code> codes;
+    codes.reserve(n_accs);
+    for (unsigned i = 0; i < n_accs; ++i)
+      if (drand() < 0.5)
+	codes.push_back(acc.inf(acc.mark(i)));
+      else
+	codes.push_back(acc.fin(acc.mark(i)));
+
+    int s = codes.size();
+    while (s > 1)
+      {
+	// Pick a random code and put it at the end
+	int p1 = mrand(s--);
+	std::swap(codes[p1], codes[s]);
+	// and another one
+	int p2 = mrand(s);
+
+	if (drand() < 0.5)
+	  codes[p2].append_or(std::move(codes.back()));
+	else
+	  codes[p2].append_and(std::move(codes.back()));
+
+	codes.pop_back();
+      }
+    return codes[0];
+  }
+
 }

src/tgbaalgos/randomgraph.hh

@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2011, 2013, 2014 Laboratoire de Recherche et
+// Copyright (C) 2011, 2013, 2014, 2015 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
@@ -25,6 +25,7 @@
 #include "ltlvisit/apcollect.hh"
 #include "ltlenv/defaultenv.hh"
 #include "tgba/bdddict.hh"
+#include "tgba/acc.hh"
 
 namespace spot
 {
@@ -81,4 +82,7 @@ namespace spot
 	       const ltl::atomic_prop_set* ap, const bdd_dict_ptr& dict,
 	       unsigned n_accs = 0, float a = 0.1, float t = 0.5,
 	       bool deterministic = false, bool state_acc = false);
+
+  /// Build a random acceptance where each acceptance sets is used once.
+  SPOT_API acc_cond::acc_code random_acceptance(unsigned n_accs);
 }

src/tgbatest/randaut.test

@@ -81,3 +81,20 @@ test 6 = `$autfilt -c out-det1.hoa`
 
 $autfilt -H out.hoa -o foo -c 2>stderr && exit 1
 grep 'autfilt: options --output and --count are incompatible' stderr
+
+$randaut -n 2 -S5 -A4 -H 2 | grep Acceptance: > output
+$randaut --acc-type=random -n 2 -S5 -A4 -H 2 | grep Acceptance: >> output
+cat output
+
+cat >expected <<EOF
+Acceptance: 4 Inf(0)&Inf(1)&Inf(2)&Inf(3)
+Acceptance: 4 Inf(0)&Inf(1)&Inf(2)&Inf(3)
+Acceptance: 4 (Fin(2) & Inf(3)) | Inf(0) | Fin(1)
+Acceptance: 4 ((Inf(0) | Inf(1)) & Fin(3)) | Inf(2)
+EOF
+diff output expected
+
+$randaut --spin --acc-type=random 2 2>stderr && exit 1
+grep 'randaut: --spin.*--acc-type' stderr
+$randaut --ba --acc-type=random 2 2>stderr && exit 1
+grep 'randaut: --ba.*--acc-type' stderr