aux.py 1.95 KB
Newer Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
# -*- coding: utf-8 -*-
# Copyright (C) 2016 Laboratoire de Recherche et Développement 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 3 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 this program.  If not, see <http://www.gnu.org/licenses/>.

"""
Auxiliary functions for Spot's Python bindings
"""

from functools import lru_cache
import subprocess


def extend(*classes):
    """
    Decorator that extends all the given classes with the contents
    of the class currently being defined.
    """
    def wrap(this):
        for cls in classes:
            for (name, val) in this.__dict__.items():
                if name not in ('__dict__', '__weakref__') \
                   and not (name == '__doc__' and val is None):
                    setattr(cls, name, val)
        return classes[0]
    return wrap


# Add a small LRU cache so that when we display automata into a
# interactive widget, we avoid some repeated calls to dot for
# identical inputs.
@lru_cache(maxsize=64)
def str_to_svg(str):
    """
    Send some text to dot for conversion to SVG.
    """
    dot = subprocess.Popen(['dot', '-Tsvg'],
                           stdin=subprocess.PIPE,
                           stdout=subprocess.PIPE)
    res = dot.communicate(str)
    return res[0].decode('utf-8')


def ostream_to_svg(ostr):
    """
    Encode an ostringstream as utf-8 and send it to dot for cocnversion to SVG.
    """
    return str_to_svg(ostr.str().encode('utf-8'))