python: add xargs support to translate() and postprocess()

Fixes #361.

* python/spot/__init__.py: Implement it.
* tests/python/optionmap.py: Test it.
* NEWS: Mention it.

NEWS

@@ -18,6 +18,16 @@ New in spot 2.6.3.dev (not yet released)
   - ltlfilt learned --liveness to match formulas representing liveness
     properties.
 
+  Python:
+
+  - spot.translate() and spot.postprocess() now take an xargs=
+    argument similar to the -x option of ltl2tgba and autfilt, making
+    it easier to fine tune these operations.  For instance
+        ltl2tgba 'GF(a <-> XXa)' --det -x gf-guarantee=0
+    would be written in Python as
+        spot.translate('GF(a <-> XXa)', 'det', xargs='gf-guarantee=0')
+    (Note: those extra options are documented in the spot-x(7) man page.)
+
   Library:
 
   - The LTL parser learned syntactic sugar for nested ranges of X

python/spot/__init__.py

@@ -101,6 +101,17 @@ if 'op_ff' not in globals():
 _bdd_dict = make_bdd_dict()
 
 
+
+__om_init_tmp = option_map.__init__
+def __om_init_new(self, str=None):
+    __om_init_tmp(self)
+    if str:
+        res = self.parse_options(str)
+        if res:
+            raise RuntimeError("failed to parse option at: '" + str +"'")
+option_map.__init__ = __om_init_new
+
+
 @_extend(twa, ta)
 class twa:
     def _repr_svg_(self, opt=None):
@@ -688,7 +699,7 @@ def _postproc_translate_options(obj, default_type, *args):
     obj.set_level(optm_)
 
 
-def translate(formula, *args, dict=_bdd_dict):
+def translate(formula, *args, dict=_bdd_dict, xargs=None):
     """Translate a formula into an automaton.
 
     Keep in mind that 'Deterministic' expresses just a preference that
@@ -708,12 +719,22 @@ def translate(formula, *args, dict=_bdd_dict):
       'Colored' (only for parity acceptance)
 
     The default corresponds to 'tgba', 'small' and 'high'.
+
+    Additional options can be supplied using a `spot.option_map`, or a
+    string (that will be converted to `spot.option_map`), as the `xargs`
+    argument.  This is similar to the `-x` option of command-line tools;
+    so check out the spot-x(7) man page for details.
     """
-    a = translator(dict)
+    if type(xargs) is str:
+        xargs = option_map(xargs)
+    a = translator(dict, xargs)
     _postproc_translate_options(a, postprocessor.TGBA, *args)
     if type(formula) == str:
         formula = parse_formula(formula)
-    return a.run(formula)
+    result = a.run(formula)
+    if xargs:
+        xargs.report_unused_options()
+    return result
 
 
 formula.translate = translate
@@ -732,7 +753,7 @@ _add_formula('contains')
 _add_formula('are_equivalent', 'equivalent_to')
 
 
-def postprocess(automaton, *args, formula=None):
+def postprocess(automaton, *args, formula=None, xargs=None):
     """Post process an automaton.
 
     This applies a number of simlification algorithms, depending on
@@ -758,12 +779,22 @@ def postprocess(automaton, *args, formula=None):
     If a formula denoted by this automaton is known, pass it to as the
     optional `formula` argument; it can help some algorithms by
     providing an easy way to complement the automaton.
-    """
-    p = postprocessor()
+
+    Additional options can be supplied using a `spot.option_map`, or a
+    string (that will be converted to `spot.option_map`), as the `xargs`
+    argument.  This is similar to the `-x` option of command-line tools;
+    so check out the spot-x(7) man page for details.
+"""
+    if type(xargs) is str:
+        xargs = option_map(xargs)
+    p = postprocessor(xargs)
     if type(automaton) == str:
         automaton = globals()['automaton'](automaton)
     _postproc_translate_options(p, postprocessor.Generic, *args)
-    return p.run(automaton, formula)
+    result = p.run(automaton, formula)
+    if xargs:
+        xargs.report_unused_options()
+    return result
 
 
 twa.postprocess = postprocess

tests/python/optionmap.py

@@ -1,5 +1,5 @@
 # -*- mode: python; coding: utf-8 -*-
-# Copyright (C) 2010, 2012 Laboratoire de Recherche et Développement
+# Copyright (C) 2010, 2012, 2018 Laboratoire de Recherche et Développement
 # de l'EPITA.
 # Copyright (C) 2005  Laboratoire d'Informatique de Paris 6 (LIP6),
 # département Systèmes Répartis Coopératifs (SRC), Université Pierre
@@ -57,3 +57,29 @@ assert res == "opt == 1"
 
 res = o.parse_options("foo=3opt == 1")
 assert res == "3opt == 1"
+
+aut1 = spot.translate('GF(a <-> XXa)', 'det')
+assert aut1.num_states() == 4
+aut2 = spot.translate('GF(a <-> XXa)', 'det', xargs='gf-guarantee=0')
+assert aut2.num_states() == 9
+
+try:
+    spot.translate('GF(a <-> XXa)', 'det', xargs='foobar=1')
+except RuntimeError as e:
+    assert "option 'foobar' was not used" in str(e)
+else:
+    raise RuntimeError("missing exception")
+
+try:
+    spot.translate('GF(a <-> XXa)').postprocess('det', xargs='gf-guarantee=0')
+except RuntimeError as e:
+    assert "option 'gf-guarantee' was not used" in str(e)
+else:
+    raise RuntimeError("missing exception")
+
+try:
+    spot.translate('GF(a <-> XXa)').postprocess('det', xargs='gf-guarantee=x')
+except RuntimeError as e:
+    assert "failed to parse option at: 'gf-guarantee=x'" in str(e)
+else:
+    raise RuntimeError("missing exception")