From 77b0b5b3fe869d6b790dfedfc2e2d5b8304ade36 Mon Sep 17 00:00:00 2001
From: Alexandre Duret-Lutz <adl@lrde.epita.fr>
Date: Fri, 5 Feb 2016 18:56:08 +0100
Subject: [PATCH] dot: add option C(COLOR)

This fixes the output gliches visible in the previous patches,
where highlighting a state would remove its fill color.

* spot/twaalgos/dot.cc, spot/taalgos/dot.cc: Implement option C(COLOR).
* bin/common_aoutput.cc, doc/org/oaut.org: Document it.
* doc/org/.dir-locals.el.in, doc/org/init.el.in,
python/spot/__init__.py: Use it.
* tests/python/automata-io.ipynb, tests/python/automata.ipynb,
tests/python/highlighting.ipynb: Test it.
* tests/core/readsave.test: Adjust.
* NEWS: Mention recent changes.
---
 NEWS                            | 30 ++++++----
 bin/common_aoutput.cc           | 10 +++-
 doc/org/.dir-locals.el.in       |  4 +-
 doc/org/init.el.in              |  5 +-
 doc/org/oaut.org                | 13 +++--
 python/spot/__init__.py         | 10 ++--
 spot/taalgos/dot.cc             | 17 ++++++
 spot/twaalgos/dot.cc            | 31 +++++++++--
 tests/core/readsave.test        |  4 +-
 tests/python/automata-io.ipynb  | 35 ++++++------
 tests/python/automata.ipynb     | 99 +++++++++++++++++----------------
 tests/python/highlighting.ipynb | 12 ++--
 12 files changed, 163 insertions(+), 107 deletions(-)

diff --git a/NEWS b/NEWS
index 3bfcd22b7..7c6a06c90 100644
--- a/NEWS
+++ b/NEWS
@@ -12,20 +12,26 @@ New in spot 1.99.7a (not yet released)
     object can be queried about the supported variables and their
     types.
 
-  * print_dot() now accepts an option of the form "<N" to specify
-    a maximum number of states to output.  Incomplete states are
-    then marked appropriately.  For a quick example, compare
-       ltl2tgba -D 'Ga | Gb | Gc' -d'<3'
-    with
-       ltl2tgba -D 'Ga | Gb | Gc' -d
-
-  * print_dot() now has option "k" to use state-based labels when
-    possible.  This is similar to the "k" option already supported
-    by print_hoa(), and is useful when printing Kripke structures.
+  * print_dot() now accepts several new options:
+    - use "<N" to specify a maximum number of states to output.
+      Incomplete states are then marked appropriately.  For a quick
+      example, compare
+	ltl2tgba -D 'Ga | Gb | Gc' -d'<3'
+      with
+        ltl2tgba -D 'Ga | Gb | Gc' -d
+    - use "C(color)" to specify the color to use for filling states.
+    - use "#" to display the internal number of each transition
+    - use "k" to use state-based labels when possible.  This is
+      similar to the "k" option already supported by print_hoa(), and
+      is useful when printing Kripke structures.
 
   * Option "k" is automatically passed used by print_dot() and
     print_hoa() when printing Kripke structures.
 
+  * print_dot() also honnor two new automaton properties called
+    "highlight-edges" and "highlight-states".  These are used to color
+    a subset of edges or transitions.
+
   Python:
 
   * The ltsmin interface has been binded in Python.  See
@@ -36,6 +42,10 @@ New in spot 1.99.7a (not yet released)
     unreadable (and slow to process by GraphViz).  This can be
     overridden by calling spot.setup(max_states=N).
 
+  * Automata now have methods to color selected states and
+    transitions.  See
+    https://spot.lrde.epita.fr/ipynb/highlighting.html for an example.
+
   Documentation:
 
   * There is a new page giving informal illustrations (and extra
diff --git a/bin/common_aoutput.cc b/bin/common_aoutput.cc
index 6af324fd8..0c7c722f0 100644
--- a/bin/common_aoutput.cc
+++ b/bin/common_aoutput.cc
@@ -80,13 +80,16 @@ static const argp_option options[] =
   {
     /**************************************************/
     { nullptr, 0, nullptr, 0, "Output format:", 3 },
-    { "dot", 'd', "1|a|b|B|c|e|f(FONT)|h|k|n|N|o|r|R|s|t|v|+INT|<INT",
+    { "dot", 'd',
+      "1|a|b|B|c|C(COLOR)|e|f(FONT)|h|k|n|N|o|r|R|s|t|v|+INT|<INT|#",
       OPTION_ARG_OPTIONAL,
       "GraphViz's format.  Add letters for "
       "(1) force numbered states, "
       "(a) acceptance display, (b) acceptance sets as bullets, "
       "(B) bullets except for Büchi/co-Büchi automata, "
-      "(c) force circular nodes, (e) force elliptic nodes, "
+      "(c) force circular nodes, "
+      "(C) color nodes with COLOR, "
+      "(e) force elliptic nodes, "
       "(f(FONT)) use FONT, (h) horizontal layout, "
       "(k) use state labels when possible, "
       "(n) with name, (N) without name, "
@@ -96,7 +99,8 @@ static const argp_option options[] =
       "(t) force transition-based acceptance, "
       "(v) vertical layout, "
       "(+INT) add INT to all set numbers, "
-      "(<INT) display at most INT states", 0 },
+      "(<INT) display at most INT states, "
+      "(#) show internal edge numbers", 0 },
     { "hoaf", 'H', "i|l|m|s|t|v", OPTION_ARG_OPTIONAL,
       "Output the automaton in HOA format (default).  Add letters to select "
       "(i) use implicit labels for complete deterministic automata, "
diff --git a/doc/org/.dir-locals.el.in b/doc/org/.dir-locals.el.in
index bfe995875..e5cbb5533 100644
--- a/doc/org/.dir-locals.el.in
+++ b/doc/org/.dir-locals.el.in
@@ -20,8 +20,8 @@
 		      (setenv "DYLD_LIBRARY_PATH"
 			      (concat "@abs_top_builddir@/python/.libs:@abs_top_builddir@/spot/.libs:@abs_top_builddir@/buddy/spot/.libs:"
 				      (getenv "DYLD_LIBRARY_PATH")))
-		      (setenv "SPOT_DOTDEFAULT" "Brf(Lato)")
-		      (setenv "SPOT_DOTEXTRA" "node[style=filled, fillcolor=\"#ffffa0\"] edge[arrowhead=vee, arrowsize=.7]")
+		      (setenv "SPOT_DOTDEFAULT" "Brf(Lato)C(#ffffa0)")
+		      (setenv "SPOT_DOTEXTRA" "edge[arrowhead=vee, arrowsize=.7]")
 		      (org-babel-do-load-languages 'org-babel-load-languages
 						   '((sh . t)
 						     (python . t)
diff --git a/doc/org/init.el.in b/doc/org/init.el.in
index f1da4bce6..46325abfc 100644
--- a/doc/org/init.el.in
+++ b/doc/org/init.el.in
@@ -43,9 +43,8 @@
 (setenv "DYLD_LIBRARY_PATH"
 	(concat "@abs_top_builddir@/python/.libs:@abs_top_builddir@/spot/.libs:@abs_top_builddir@/buddy/spot/.libs:"
 		(getenv "DYLD_LIBRARY_PATH")))
-(setenv "SPOT_DOTDEFAULT" "Brf(Lato)")
-(setenv "SPOT_DOTEXTRA"
- "node[style=filled, fillcolor=\"#ffffa0\"] edge[arrowhead=vee, arrowsize=.7]")
+(setenv "SPOT_DOTDEFAULT" "Brf(Lato)C(#ffffa0)")
+(setenv "SPOT_DOTEXTRA" "edge[arrowhead=vee, arrowsize=.7]")
 
 (setq org-export-html-home/up-format
 "<div id=\"org-div-home-and-up\" style=\"text-align:center;white-space:nowrap;\">
diff --git a/doc/org/oaut.org b/doc/org/oaut.org
index 204348ddd..5ad6aa41a 100644
--- a/doc/org/oaut.org
+++ b/doc/org/oaut.org
@@ -579,10 +579,11 @@ acceptance condition to be shown as well.  Option =b= causes sets to
 be ouput as bullets (e.g., ⓿ instead of ={0}=); option =r= (for
 rainbow) causes sets to be displayed in different colors, while option
 =R= also uses colors, but it chooses them depending on whether a set
-is used with Fin-acceptance, Inf-acceptance, or both.  Finally option
-=f(FONT)= is used to select a fontname: it is often necessary when =b=
-is used to ensure the characters ⓿, ❶, etc. are all selected from the
-same font.
+is used with Fin-acceptance, Inf-acceptance, or both.  Option
+=C(COLOR)= can be used to color all states using =COLOR=, and the
+option =f(FONT)= is used to select a fontname: it is often necessary
+when =b= is used to ensure the characters ⓿, ❶, etc. are all selected
+from the same font.
 
 #+BEGIN_SRC sh :results verbatim :exports code
 ltl2tgba --dot=vcsna '(Ga -> Gb) W c'
@@ -840,8 +841,8 @@ The dot output can also be customized via two environment variables:
   variables set:
 
 #+BEGIN_SRC sh :results verbatim :exports code
-export SPOT_DOTDEFAULT='Brf(Lato)'
-export SPOT_DOTEXTRA='node[style=filled, fillcolor="#ffffa0"] edge[arrowhead=vee, arrowsize=.7]'
+export SPOT_DOTDEFAULT='Brf(Lato)C(#ffffa0)'
+export SPOT_DOTEXTRA='edge[arrowhead=vee, arrowsize=.7]'
 #+END_SRC
 
 * Statistics
diff --git a/python/spot/__init__.py b/python/spot/__init__.py
index 8b523df5a..e5c9a1238 100644
--- a/python/spot/__init__.py
+++ b/python/spot/__init__.py
@@ -76,14 +76,14 @@ def setup(**kwargs):
     """
     import os
 
-    s = ('size="{}" node[style=filled,fillcolor="{}"] '
-         'edge[arrowhead=vee, arrowsize=.7]')
-    os.environ['SPOT_DOTEXTRA'] = s.format(kwargs.get('size', '10.2,5'),
-                                           kwargs.get('fillcolor', '#ffffaa'))
+    s = ('size="{}" edge[arrowhead=vee, arrowsize=.7]')
+    os.environ['SPOT_DOTEXTRA'] = s.format(kwargs.get('size', '10.2,5'))
 
     bullets = 'B' if kwargs.get('bullets', True) else ''
     max_states = '<' + str(kwargs.get('max_states', 50))
-    d = 'rf({})'.format(kwargs.get('font', 'Lato')) + bullets + max_states
+    d = 'rf({})C({}){}'.format(kwargs.get('font', 'Lato'),
+                               kwargs.get('fillcolor', '#ffffaa'),
+                               bullets + max_states)
     global _show_default
     _show_default = kwargs.get('show_default', None)
     os.environ['SPOT_DOTDEFAULT'] = d
diff --git a/spot/taalgos/dot.cc b/spot/taalgos/dot.cc
index b42ec87b2..fb20cc78a 100644
--- a/spot/taalgos/dot.cc
+++ b/spot/taalgos/dot.cc
@@ -65,6 +65,19 @@ namespace spot
 	    case 'c':
 	      opt_circles_ = true;
 	      break;
+	    case 'C':
+	      if (*options != '(')
+		throw std::runtime_error
+		  ("invalid node color specification for print_dot()");
+	      {
+		auto* end = strchr(++options, ')');
+		if (!end)
+		  throw std::runtime_error
+		    ("invalid node color specification for print_dot()");
+		opt_node_color_ = std::string(options, end - options);
+		options = end + 1;
+	      }
+	      break;
 	    case 'h':
 	      opt_horizontal_ = true;
 	      break;
@@ -136,6 +149,9 @@ namespace spot
 	  os_ << "  rankdir=LR\n";
 	if (opt_circles_)
 	  os_ << "  node [shape=\"circle\"]\n";
+	if (!opt_node_color_.empty())
+	  os_ << "  node [style=\"filled\", fillcolor=\""
+	      << opt_node_color_ << "\"]\n";
 	if (!opt_font_.empty())
 	  os_ << "  fontname=\"" << opt_font_
 	      << "\"\n  node [fontname=\"" << opt_font_
@@ -238,6 +254,7 @@ namespace spot
       bool opt_circles_ = false;
       bool opt_hide_sets_ = false;
       std::string opt_font_;
+      std::string opt_node_color_;
     };
 
   }
diff --git a/spot/twaalgos/dot.cc b/spot/twaalgos/dot.cc
index a3d00975c..9acfcd2fd 100644
--- a/spot/twaalgos/dot.cc
+++ b/spot/twaalgos/dot.cc
@@ -75,6 +75,7 @@ namespace spot
       bool opt_want_state_names_ = true;
       unsigned opt_shift_sets_ = 0;
       std::string opt_font_;
+      std::string opt_node_color_;
 
       const char* const palette9[9] =
 	{
@@ -181,18 +182,31 @@ namespace spot
 	    case 'c':
 	      opt_shape_ = ShapeCircle;
 	      break;
+	    case 'C':
+	      if (*options != '(')
+		throw std::runtime_error
+		  ("invalid node color specification for print_dot()");
+	      {
+		auto* end = strchr(++options, ')');
+		if (!end)
+		  throw std::runtime_error
+		    ("invalid node color specification for print_dot()");
+		opt_node_color_ = std::string(options, end - options);
+		options = end + 1;
+	      }
+	      break;
 	    case 'e':
 	      opt_shape_ = ShapeEllipse;
 	      break;
 	    case 'f':
 	      if (*options != '(')
 		throw std::runtime_error
-		  (std::string("invalid font specification for dotty()"));
+		  ("invalid font specification for print_dot()");
 	      {
 		auto* end = strchr(++options, ')');
 		if (!end)
 		  throw std::runtime_error
-		    (std::string("invalid font specification for dotty()"));
+		    ("invalid font specification for print_dot()");
 		opt_font_ = std::string(options, end - options);
 		options = end + 1;
 	      }
@@ -406,6 +420,9 @@ namespace spot
 	  case ShapeAuto:
 	    SPOT_UNREACHABLE();
 	  }
+	if (!opt_node_color_.empty())
+	  os_ << "  node [style=\"filled\", fillcolor=\""
+	      << opt_node_color_ << "\"]\n";
 	if (!opt_font_.empty())
 	  os_ << "  fontname=\"" << opt_font_
 	      << "\"\n  node [fontname=\"" << opt_font_
@@ -511,9 +528,13 @@ namespace spot
 	  {
 	    auto iter = highlight_states_->find(s);
 	    if (iter != highlight_states_->end())
-	      os_ << ", style=bold, color=\""
-		  << palette[iter->second % palette_mod]
-		  << '"';
+	      {
+		os_ << ", style=\"bold";
+		if (!opt_node_color_.empty())
+		  os_ << ",filled";
+		os_ << "\", color=\"" << palette[iter->second % palette_mod]
+		    << '"';
+	      }
 	  }
 	os_ << "]\n";
 	if (incomplete_ && incomplete_->find(s) != incomplete_->end())
diff --git a/tests/core/readsave.test b/tests/core/readsave.test
index f37b8869d..a0eb63e59 100755
--- a/tests/core/readsave.test
+++ b/tests/core/readsave.test
@@ -993,12 +993,12 @@ digraph G {
   node [shape="circle"]
   I [label="", style=invis, width=0]
   I -> 2
-  0 [label="0", peripheries=2, style=bold, color="#5DA5DA"]
+  0 [label="0", peripheries=2, style="bold", color="#5DA5DA"]
   0 -> 0 [label="1", style=bold, color="#5DA5DA"]
   1 [label="1"]
   1 -> 0 [label="c", style=bold, color="#F17CB0"]
   1 -> 1 [label="b & !c", style=bold, color="#FAA43A"]
-  2 [label="2", style=bold, color="#B276B2"]
+  2 [label="2", style="bold", color="#B276B2"]
   2 -> 0 [label="c", style=bold, color="#B276B2"]
   2 -> 1 [label="!a & b & !c"]
   2 -> 2 [label="a & !c"]
diff --git a/tests/python/automata-io.ipynb b/tests/python/automata-io.ipynb
index a018a5a95..ccd65aa77 100644
--- a/tests/python/automata-io.ipynb
+++ b/tests/python/automata-io.ipynb
@@ -18,7 +18,7 @@
    "version": "3.4.3+"
   },
   "name": "",
-  "signature": "sha256:79ee85572b2a0147d88b2d3d355977e3f34dadb82bd7e8589bdbb2cf2a539b0b"
+  "signature": "sha256:d9763e3af9f29bca127bdbfb9c6b0bcfaf276a0c32d9f789d696bfbe4a563e57"
  },
  "nbformat": 3,
  "nbformat_minor": 0,
@@ -81,10 +81,11 @@
         "digraph G {\n",
         "  rankdir=LR\n",
         "  node [shape=\"circle\"]\n",
+        "  node [style=\"filled\", fillcolor=\"#ffffaa\"]\n",
         "  fontname=\"Lato\"\n",
         "  node [fontname=\"Lato\"]\n",
         "  edge [fontname=\"Lato\"]\n",
-        "  size=\"10.2,5\" node[style=filled,fillcolor=\"#ffffaa\"] edge[arrowhead=vee, arrowsize=.7]\n",
+        "  size=\"10.2,5\" edge[arrowhead=vee, arrowsize=.7]\n",
         "  I [label=\"\", style=invis, width=0]\n",
         "  I -> 1\n",
         "  0 [label=\"0\", peripheries=2]\n",
@@ -172,7 +173,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f4414147600> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f45201e0810> >"
        ]
       }
      ],
@@ -283,7 +284,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f4414157570> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f45201e09c0> >"
        ]
       },
       {
@@ -340,7 +341,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f4414157660> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f45201ff1b0> >"
        ]
       }
      ],
@@ -459,7 +460,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f441765be40> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f45201e0900> >"
        ]
       }
      ],
@@ -554,7 +555,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f4414157690> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f45201ff1b0> >"
        ]
       },
       {
@@ -602,7 +603,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f441765be40> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f45201e0900> >"
        ]
       }
      ],
@@ -717,7 +718,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f44141578d0> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f45201ff390> >"
        ]
       },
       {
@@ -789,7 +790,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f44141578a0> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f45201ff270> >"
        ]
       }
      ],
@@ -811,8 +812,8 @@
        "traceback": [
         "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m\n\u001b[0;31mCalledProcessError\u001b[0m                        Traceback (most recent call last)",
         "\u001b[0;32m<ipython-input-12-2b2d1b66dcd6>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mspot\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mautomaton\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m'non-existing-cmd |'\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
-        "\u001b[0;32m/home/adl/git/spot/wrap/python/spot.py\u001b[0m in \u001b[0;36mautomaton\u001b[0;34m(filename, **kwargs)\u001b[0m\n\u001b[1;32m    404\u001b[0m     See `spot.automata` for a list of supported formats.\"\"\"\n\u001b[1;32m    405\u001b[0m     \u001b[0;32mtry\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 406\u001b[0;31m         \u001b[0;32mreturn\u001b[0m \u001b[0mnext\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mautomata\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mfilename\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;34m**\u001b[0m\u001b[0mkwargs\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    407\u001b[0m     \u001b[0;32mexcept\u001b[0m \u001b[0mStopIteration\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    408\u001b[0m         \u001b[0;32mraise\u001b[0m \u001b[0mRuntimeError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"Failed to read automaton from {}\"\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mformat\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mfilename\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
-        "\u001b[0;32m/home/adl/git/spot/wrap/python/spot.py\u001b[0m in \u001b[0;36mautomata\u001b[0;34m(timeout, *sources)\u001b[0m\n\u001b[1;32m    395\u001b[0m                 \u001b[0;32mdel\u001b[0m \u001b[0mproc\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    396\u001b[0m                 \u001b[0;32mif\u001b[0m \u001b[0mret\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 397\u001b[0;31m                     \u001b[0;32mraise\u001b[0m \u001b[0msubprocess\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mCalledProcessError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mret\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mfilename\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m-\u001b[0m\u001b[0;36m1\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    398\u001b[0m     \u001b[0;32mreturn\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    399\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n",
+        "\u001b[0;32m/home/adl/git/spot/python/spot/__init__.py\u001b[0m in \u001b[0;36mautomaton\u001b[0;34m(filename, **kwargs)\u001b[0m\n\u001b[1;32m    471\u001b[0m     See `spot.automata` for a list of supported formats.\"\"\"\n\u001b[1;32m    472\u001b[0m     \u001b[0;32mtry\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 473\u001b[0;31m         \u001b[0;32mreturn\u001b[0m \u001b[0mnext\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mautomata\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mfilename\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;34m**\u001b[0m\u001b[0mkwargs\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    474\u001b[0m     \u001b[0;32mexcept\u001b[0m \u001b[0mStopIteration\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    475\u001b[0m         \u001b[0;32mraise\u001b[0m \u001b[0mRuntimeError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"Failed to read automaton from {}\"\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mformat\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mfilename\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
+        "\u001b[0;32m/home/adl/git/spot/python/spot/__init__.py\u001b[0m in \u001b[0;36mautomata\u001b[0;34m(timeout, ignore_abort, trust_hoa, debug, *sources)\u001b[0m\n\u001b[1;32m    456\u001b[0m                 \u001b[0;32mdel\u001b[0m \u001b[0mproc\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    457\u001b[0m                 \u001b[0;32mif\u001b[0m \u001b[0mret\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 458\u001b[0;31m                     \u001b[0;32mraise\u001b[0m \u001b[0msubprocess\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mCalledProcessError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mret\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mfilename\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m-\u001b[0m\u001b[0;36m1\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    459\u001b[0m     \u001b[0;31m# deleting o explicitely now prevents Python 3.5 from\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    460\u001b[0m     \u001b[0;31m# reporting the following error: \"<built-in function\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
         "\u001b[0;31mCalledProcessError\u001b[0m: Command 'non-existing-cmd ' returned non-zero exit status 127"
        ]
       }
@@ -835,9 +836,11 @@
        "traceback": [
         "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m\n\u001b[0;31mTimeoutExpired\u001b[0m                            Traceback (most recent call last)",
         "\u001b[0;32m<ipython-input-13-d9c814f4e517>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mspot\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mautomaton\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m'sleep 3; cat example.aut |'\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mtimeout\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0;36m1\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
-        "\u001b[0;32m/home/adl/git/spot/wrap/python/spot.py\u001b[0m in \u001b[0;36mautomaton\u001b[0;34m(filename, **kwargs)\u001b[0m\n\u001b[1;32m    404\u001b[0m     See `spot.automata` for a list of supported formats.\"\"\"\n\u001b[1;32m    405\u001b[0m     \u001b[0;32mtry\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 406\u001b[0;31m         \u001b[0;32mreturn\u001b[0m \u001b[0mnext\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mautomata\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mfilename\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;34m**\u001b[0m\u001b[0mkwargs\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    407\u001b[0m     \u001b[0;32mexcept\u001b[0m \u001b[0mStopIteration\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    408\u001b[0m         \u001b[0;32mraise\u001b[0m \u001b[0mRuntimeError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"Failed to read automaton from {}\"\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mformat\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mfilename\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
-        "\u001b[0;32m/home/adl/git/spot/wrap/python/spot.py\u001b[0m in \u001b[0;36mautomata\u001b[0;34m(timeout, *sources)\u001b[0m\n\u001b[1;32m    366\u001b[0m                 \u001b[0;32melse\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    367\u001b[0m                     out = subprocess.check_output(filename[:-1], shell=True,\n\u001b[0;32m--> 368\u001b[0;31m                                                   timeout=timeout)\n\u001b[0m\u001b[1;32m    369\u001b[0m                     \u001b[0mp\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mautomaton_stream_parser\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mout\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mfilename\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;32mTrue\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    370\u001b[0m             \u001b[0;32melif\u001b[0m \u001b[0;34m'\\n'\u001b[0m \u001b[0;32min\u001b[0m \u001b[0mfilename\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
-        "\u001b[0;32m/usr/lib/python3.4/subprocess.py\u001b[0m in \u001b[0;36mcheck_output\u001b[0;34m(timeout, *popenargs, **kwargs)\u001b[0m\n\u001b[1;32m    611\u001b[0m             \u001b[0mprocess\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mkill\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    612\u001b[0m             \u001b[0moutput\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0munused_err\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mprocess\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mcommunicate\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 613\u001b[0;31m             \u001b[0;32mraise\u001b[0m \u001b[0mTimeoutExpired\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mprocess\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0margs\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mtimeout\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0moutput\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0moutput\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    614\u001b[0m         \u001b[0;32mexcept\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    615\u001b[0m             \u001b[0mprocess\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mkill\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
+        "\u001b[0;32m/home/adl/git/spot/python/spot/__init__.py\u001b[0m in \u001b[0;36mautomaton\u001b[0;34m(filename, **kwargs)\u001b[0m\n\u001b[1;32m    471\u001b[0m     See `spot.automata` for a list of supported formats.\"\"\"\n\u001b[1;32m    472\u001b[0m     \u001b[0;32mtry\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 473\u001b[0;31m         \u001b[0;32mreturn\u001b[0m \u001b[0mnext\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mautomata\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mfilename\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0;34m**\u001b[0m\u001b[0mkwargs\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    474\u001b[0m     \u001b[0;32mexcept\u001b[0m \u001b[0mStopIteration\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    475\u001b[0m         \u001b[0;32mraise\u001b[0m \u001b[0mRuntimeError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"Failed to read automaton from {}\"\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mformat\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mfilename\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
+        "\u001b[0;32m/home/adl/git/spot/python/spot/__init__.py\u001b[0m in \u001b[0;36mautomata\u001b[0;34m(timeout, ignore_abort, trust_hoa, debug, *sources)\u001b[0m\n\u001b[1;32m    415\u001b[0m                 \u001b[0;32melse\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    416\u001b[0m                     \u001b[0;32mtry\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 417\u001b[0;31m                         \u001b[0mout\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0merr\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mproc\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mcommunicate\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mtimeout\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0mtimeout\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    418\u001b[0m                     \u001b[0;32mexcept\u001b[0m \u001b[0msubprocess\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mTimeoutExpired\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    419\u001b[0m                         \u001b[0;31m# Using subprocess.check_output() with timeout\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
+        "\u001b[0;32m/usr/lib/python3.5/subprocess.py\u001b[0m in \u001b[0;36mcommunicate\u001b[0;34m(self, input, timeout)\u001b[0m\n\u001b[1;32m   1063\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   1064\u001b[0m             \u001b[0;32mtry\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m-> 1065\u001b[0;31m                 \u001b[0mstdout\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mstderr\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0m_communicate\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0minput\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mendtime\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mtimeout\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m   1066\u001b[0m             \u001b[0;32mfinally\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   1067\u001b[0m                 \u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0m_communication_started\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0;32mTrue\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
+        "\u001b[0;32m/usr/lib/python3.5/subprocess.py\u001b[0m in \u001b[0;36m_communicate\u001b[0;34m(self, input, endtime, orig_timeout)\u001b[0m\n\u001b[1;32m   1698\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   1699\u001b[0m                     \u001b[0mready\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mselector\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mselect\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mtimeout\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m-> 1700\u001b[0;31m                     \u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0m_check_timeout\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mendtime\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0morig_timeout\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m   1701\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   1702\u001b[0m                     \u001b[0;31m# XXX Rewrite these to use non-blocking I/O on the file\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
+        "\u001b[0;32m/usr/lib/python3.5/subprocess.py\u001b[0m in \u001b[0;36m_check_timeout\u001b[0;34m(self, endtime, orig_timeout)\u001b[0m\n\u001b[1;32m   1089\u001b[0m             \u001b[0;32mreturn\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   1090\u001b[0m         \u001b[0;32mif\u001b[0m \u001b[0m_time\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m)\u001b[0m \u001b[0;34m>\u001b[0m \u001b[0mendtime\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m-> 1091\u001b[0;31m             \u001b[0;32mraise\u001b[0m \u001b[0mTimeoutExpired\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0margs\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0morig_timeout\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m   1092\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m   1093\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n",
         "\u001b[0;31mTimeoutExpired\u001b[0m: Command 'sleep 3; cat example.aut ' timed out after 1 seconds"
        ]
       }
@@ -859,4 +862,4 @@
    "metadata": {}
   }
  ]
-}
+}
\ No newline at end of file
diff --git a/tests/python/automata.ipynb b/tests/python/automata.ipynb
index 8d32d9d05..8fda68e28 100644
--- a/tests/python/automata.ipynb
+++ b/tests/python/automata.ipynb
@@ -17,7 +17,8 @@
    "pygments_lexer": "ipython3",
    "version": "3.4.3+"
   },
-  "name": ""
+  "name": "",
+  "signature": "sha256:93ecf5f37287bb2a03dcd63d41faa06f0ed9d8bcc403c73b24d1bf10404b3b1c"
  },
  "nbformat": 3,
  "nbformat_minor": 0,
@@ -177,7 +178,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f3c25174540> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f7cfc093810> >"
        ]
       }
      ],
@@ -211,7 +212,7 @@
         "<!-- I -->\n",
         "<!-- 0 -->\n",
         "<g class=\"node\" id=\"node2\"><title>0</title>\n",
-        "<ellipse cx=\"120.356\" cy=\"-287\" fill=\"#ffffaa\" rx=\"18\" ry=\"18\" stroke=\"black\"/>\n",
+        "<ellipse cx=\"120.356\" cy=\"-287\" fill=\"none\" rx=\"18\" ry=\"18\" stroke=\"black\"/>\n",
         "<text font-family=\"Times,serif\" font-size=\"14.00\" text-anchor=\"middle\" x=\"120.356\" y=\"-283.3\">0</text>\n",
         "</g>\n",
         "<!-- I&#45;&gt;0 -->\n",
@@ -227,7 +228,7 @@
         "</g>\n",
         "<!-- 1 -->\n",
         "<g class=\"node\" id=\"node3\"><title>1</title>\n",
-        "<ellipse cx=\"67.3561\" cy=\"-196\" fill=\"#ffffaa\" rx=\"18\" ry=\"18\" stroke=\"black\"/>\n",
+        "<ellipse cx=\"67.3561\" cy=\"-196\" fill=\"none\" rx=\"18\" ry=\"18\" stroke=\"black\"/>\n",
         "<ellipse cx=\"67.3561\" cy=\"-196\" fill=\"none\" rx=\"22\" ry=\"22\" stroke=\"black\"/>\n",
         "<text font-family=\"Times,serif\" font-size=\"14.00\" text-anchor=\"middle\" x=\"67.3561\" y=\"-192.3\">1</text>\n",
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@@ -239,7 +240,7 @@
         "</g>\n",
         "<!-- 4 -->\n",
         "<g class=\"node\" id=\"node4\"><title>4</title>\n",
-        "<ellipse cx=\"175.356\" cy=\"-196\" fill=\"#ffffaa\" rx=\"18\" ry=\"18\" stroke=\"black\"/>\n",
+        "<ellipse cx=\"175.356\" cy=\"-196\" fill=\"none\" rx=\"18\" ry=\"18\" stroke=\"black\"/>\n",
         "<text font-family=\"Times,serif\" font-size=\"14.00\" text-anchor=\"middle\" x=\"175.356\" y=\"-192.3\">4</text>\n",
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         "<!-- 0&#45;&gt;4 -->\n",
@@ -256,7 +257,7 @@
         "</g>\n",
         "<!-- 2 -->\n",
         "<g class=\"node\" id=\"node5\"><title>2</title>\n",
-        "<ellipse cx=\"68.3561\" cy=\"-18\" fill=\"#ffffaa\" rx=\"18\" ry=\"18\" stroke=\"black\"/>\n",
+        "<ellipse cx=\"68.3561\" cy=\"-18\" fill=\"none\" rx=\"18\" ry=\"18\" stroke=\"black\"/>\n",
         "<text font-family=\"Times,serif\" font-size=\"14.00\" text-anchor=\"middle\" x=\"68.3561\" y=\"-14.3\">2</text>\n",
         "</g>\n",
         "<!-- 1&#45;&gt;2 -->\n",
@@ -267,7 +268,7 @@
         "</g>\n",
         "<!-- 3 -->\n",
         "<g class=\"node\" id=\"node6\"><title>3</title>\n",
-        "<ellipse cx=\"68.3561\" cy=\"-105\" fill=\"#ffffaa\" rx=\"18\" ry=\"18\" stroke=\"black\"/>\n",
+        "<ellipse cx=\"68.3561\" cy=\"-105\" fill=\"none\" rx=\"18\" ry=\"18\" stroke=\"black\"/>\n",
         "<text font-family=\"Times,serif\" font-size=\"14.00\" text-anchor=\"middle\" x=\"68.3561\" y=\"-101.3\">3</text>\n",
         "</g>\n",
         "<!-- 1&#45;&gt;3 -->\n",
@@ -316,7 +317,7 @@
         "</svg>"
        ],
        "text": [
-        "<IPython.core.display.SVG object>"
+        "<IPython.core.display.SVG at 0x7f7cff347ef0>"
        ]
       }
      ],
@@ -469,7 +470,7 @@
         "</svg>"
        ],
        "text": [
-        "<IPython.core.display.SVG object>"
+        "<IPython.core.display.SVG at 0x7f7d034410f0>"
        ]
       }
      ],
@@ -569,7 +570,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f3c2515b810> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f7cef37ee10> >"
        ]
       }
      ],
@@ -639,7 +640,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f3c2515b690> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f7cef37ecc0> >"
        ]
       }
      ],
@@ -715,7 +716,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f3c2515b6f0> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f7cef37ed50> >"
        ]
       }
      ],
@@ -755,7 +756,7 @@
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "f.translate('ba', 'small').show('v')"
+      "f.translate('ba', 'small').show('.v')"
      ],
      "language": "python",
      "metadata": {},
@@ -765,15 +766,15 @@
        "output_type": "pyout",
        "prompt_number": 10,
        "svg": [
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+        "<svg height=\"177pt\" viewBox=\"0.00 0.00 253.00 177.00\" width=\"253pt\" xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\">\n",
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-        "<polygon fill=\"white\" points=\"-4,4 -4,-173 247,-173 247,4 -4,4\" stroke=\"none\"/>\n",
+        "<polygon fill=\"white\" points=\"-4,4 -4,-173 249,-173 249,4 -4,4\" stroke=\"none\"/>\n",
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         "<g class=\"node\" id=\"node2\"><title>0</title>\n",
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-        "<text font-family=\"Times,serif\" font-size=\"14.00\" text-anchor=\"middle\" x=\"109\" y=\"-109.3\">0</text>\n",
+        "<text font-family=\"Lato\" font-size=\"14.00\" text-anchor=\"middle\" x=\"109\" y=\"-109.3\">0</text>\n",
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@@ -784,61 +785,61 @@
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-        "<text font-family=\"Times,serif\" font-size=\"14.00\" text-anchor=\"middle\" x=\"22\" y=\"-18.3\">1</text>\n",
+        "<text font-family=\"Lato\" font-size=\"14.00\" text-anchor=\"middle\" x=\"22\" y=\"-18.3\">1</text>\n",
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         "<g class=\"edge\" id=\"edge2\"><title>0-&gt;1</title>\n",
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+        "<text font-family=\"Lato\" font-size=\"14.00\" text-anchor=\"middle\" x=\"109\" y=\"-18.3\">2</text>\n",
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+        "<ellipse cx=\"198\" cy=\"-22\" fill=\"none\" rx=\"22\" ry=\"22\" stroke=\"black\"/>\n",
+        "<text font-family=\"Lato\" font-size=\"14.00\" text-anchor=\"middle\" x=\"198\" y=\"-18.3\">3</text>\n",
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+        "<text font-family=\"Lato\" font-size=\"14.00\" text-anchor=\"start\" x=\"62\" y=\"-18.3\">a</text>\n",
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+        "<text font-family=\"Lato\" font-size=\"14.00\" text-anchor=\"start\" x=\"149\" y=\"-18.3\">b</text>\n",
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-        "<text font-family=\"Times,serif\" font-size=\"14.00\" text-anchor=\"middle\" x=\"239.5\" y=\"-18.3\">c</text>\n",
+        "<path d=\"M218.581,-30.3702C228.845,-31.5284 238,-28.7383 238,-22 238,-16.9463 232.85,-14.1134 225.945,-13.5015\" fill=\"none\" stroke=\"black\"/>\n",
+        "<polygon fill=\"black\" points=\"218.581,-13.6298 225.525,-10.3582 222.08,-13.5688 225.58,-13.5077 225.58,-13.5077 225.58,-13.5077 222.08,-13.5688 225.635,-16.6573 218.581,-13.6298 218.581,-13.6298\" stroke=\"black\"/>\n",
+        "<text font-family=\"Lato\" font-size=\"14.00\" text-anchor=\"start\" x=\"238\" y=\"-18.3\">c</text>\n",
         "</g>\n",
         "</g>\n",
         "</svg>"
        ],
        "text": [
-        "<IPython.core.display.SVG object>"
+        "<IPython.core.display.SVG at 0x7f7ced200cc0>"
        ]
       }
      ],
@@ -1028,7 +1029,7 @@
         "</svg>"
        ],
        "text": [
-        "<IPython.core.display.SVG object>"
+        "<IPython.core.display.SVG at 0x7f7ced19d7f0>"
        ]
       }
      ],
@@ -1175,7 +1176,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f3c2515be10> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f7cef37ef60> >"
        ]
       }
      ],
@@ -1276,7 +1277,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f3c2515bed0> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f7cef37ef30> >"
        ]
       }
      ],
@@ -1394,7 +1395,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f3c2515b630> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f7cef37ef00> >"
        ]
       }
      ],
@@ -1493,7 +1494,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f3c2515b6c0> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f7cef37ed20> >"
        ]
       }
      ],
@@ -1963,7 +1964,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f3c2515b450> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f7cef37ef90> >"
        ]
       }
      ],
@@ -2160,7 +2161,7 @@
         "</svg>"
        ],
        "text": [
-        "<IPython.core.display.SVG object>"
+        "<IPython.core.display.SVG at 0x7f7ced19d5c0>"
        ]
       },
       {
@@ -2285,7 +2286,7 @@
         "</svg>"
        ],
        "text": [
-        "<IPython.core.display.SVG object>"
+        "<IPython.core.display.SVG at 0x7f7d03411e10>"
        ]
       },
       {
@@ -2427,7 +2428,7 @@
         "</svg>"
        ],
        "text": [
-        "<IPython.core.display.SVG object>"
+        "<IPython.core.display.SVG at 0x7f7ced1fa710>"
        ]
       },
       {
@@ -2578,7 +2579,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f3c2515b840> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f7cef37ecf0> >"
        ]
       }
      ],
@@ -2734,7 +2735,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f3c250f61e0> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f7cef37eed0> >"
        ]
       }
      ],
@@ -2804,7 +2805,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f3c250f6150> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f7cef37ecf0> >"
        ]
       }
      ],
@@ -2876,7 +2877,7 @@
         "</svg>"
        ],
        "text": [
-        "<IPython.core.display.SVG object>"
+        "<IPython.core.display.SVG at 0x7f7ced1863c8>"
        ]
       },
       {
@@ -2929,7 +2930,7 @@
         "</svg>"
        ],
        "text": [
-        "<IPython.core.display.SVG object>"
+        "<IPython.core.display.SVG at 0x7f7ced1913c8>"
        ]
       },
       {
@@ -3041,7 +3042,7 @@
         "</svg>"
        ],
        "text": [
-        "<IPython.core.display.SVG object>"
+        "<IPython.core.display.SVG at 0x7f7ced18d160>"
        ]
       },
       {
@@ -3153,7 +3154,7 @@
         "</svg>"
        ],
        "text": [
-        "<IPython.core.display.SVG object>"
+        "<IPython.core.display.SVG at 0x7f7ced1b7668>"
        ]
       }
      ],
@@ -3166,7 +3167,7 @@
      "language": "python",
      "metadata": {},
      "outputs": [],
-     "prompt_number": null
+     "prompt_number": 23
     }
    ],
    "metadata": {}
diff --git a/tests/python/highlighting.ipynb b/tests/python/highlighting.ipynb
index 37132f41d..68d96658b 100644
--- a/tests/python/highlighting.ipynb
+++ b/tests/python/highlighting.ipynb
@@ -1,7 +1,7 @@
 {
  "metadata": {
   "name": "",
-  "signature": "sha256:f1eb908ff21cb1cb844770da8e495a79965a4e6417793313eb447ba80378f4b4"
+  "signature": "sha256:c89800970357ab95bbed91a11bd8f6c61d1861b3fb1fb1edf133500904e3a355"
  },
  "nbformat": 3,
  "nbformat_minor": 0,
@@ -124,7 +124,7 @@
         "</svg>"
        ],
        "text": [
-        "<IPython.core.display.SVG at 0x7f295bcccd68>"
+        "<IPython.core.display.SVG at 0x7f6f6408cda0>"
        ]
       }
      ],
@@ -224,7 +224,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f29585c6810> >"
+        "<spot.impl.twa_graph; proxy of <Swig Object of type 'std::shared_ptr< spot::twa_graph > *' at 0x7f6f600c1690> >"
        ]
       }
      ],
@@ -283,7 +283,7 @@
         "</g>\n",
         "<!-- 0 -->\n",
         "<g id=\"node3\" class=\"node\"><title>0</title>\n",
-        "<ellipse fill=\"none\" stroke=\"#5da5da\" stroke-width=\"2\" cx=\"277\" cy=\"-76\" rx=\"18\" ry=\"18\"/>\n",
+        "<ellipse fill=\"#ffffaa\" stroke=\"#5da5da\" stroke-width=\"2\" cx=\"277\" cy=\"-76\" rx=\"18\" ry=\"18\"/>\n",
         "<ellipse fill=\"none\" stroke=\"#5da5da\" stroke-width=\"2\" cx=\"277\" cy=\"-76\" rx=\"22\" ry=\"22\"/>\n",
         "<text text-anchor=\"middle\" x=\"277\" y=\"-72.3\" font-family=\"Lato\" font-size=\"14.00\">0</text>\n",
         "</g>\n",
@@ -295,7 +295,7 @@
         "</g>\n",
         "<!-- 1 -->\n",
         "<g id=\"node4\" class=\"node\"><title>1</title>\n",
-        "<ellipse fill=\"none\" stroke=\"#5da5da\" stroke-width=\"2\" cx=\"194\" cy=\"-18\" rx=\"18\" ry=\"18\"/>\n",
+        "<ellipse fill=\"#ffffaa\" stroke=\"#5da5da\" stroke-width=\"2\" cx=\"194\" cy=\"-18\" rx=\"18\" ry=\"18\"/>\n",
         "<text text-anchor=\"start\" x=\"189.5\" y=\"-14.3\" font-family=\"Lato\" font-size=\"14.00\">1</text>\n",
         "</g>\n",
         "<!-- 2&#45;&gt;1 -->\n",
@@ -326,7 +326,7 @@
         "</svg>\n"
        ],
        "text": [
-        "<spot.twa; proxy of <Swig Object of type 'std::shared_ptr< spot::twa > *' at 0x7f295853bcc0> >"
+        "<spot.twa; proxy of <Swig Object of type 'std::shared_ptr< spot::twa > *' at 0x7f6f60140b40> >"
        ]
       }
      ],