tests: replace all "assert" by unittest assertions

If the assert fails because of a comparison, it is useful that the
test suite log contains a comparison of these values.
unittest.assertEqual() and friends do that for us.

* HACKING: Add a section about Python tests.
* tests/sanity/style.test: Forbid the use of "assert" in
Python tests.
* tests/python/298.py, tests/python/341.py, tests/python/471.py,
tests/python/accparse2.py, tests/python/aiger.py,
tests/python/aliases.py, tests/python/alternating.py,
tests/python/bdddict.py, tests/python/bdditer.py,
tests/python/bugdet.py, tests/python/complement_semidet.py,
tests/python/declenv.py, tests/python/decompose_scc.py,
tests/python/det.py, tests/python/dualize.py, tests/python/ecfalse.py,
tests/python/except.py, tests/python/game.py, tests/python/gen.py,
tests/python/genem.py, tests/python/implies.py,
tests/python/intrun.py, tests/python/kripke.py,
tests/python/langmap.py, tests/python/ltl2tgba.py,
tests/python/ltlf.py, tests/python/ltlparse.py,
tests/python/ltlsimple.py, tests/python/mealy.py,
tests/python/merge.py, tests/python/mergedge.py,
tests/python/misc-ec.py, tests/python/optionmap.py,
tests/python/origstate.py, tests/python/otfcrash.py,
tests/python/parity.py, tests/python/parsetgba.py,
tests/python/pdegen.py, tests/python/prodexpt.py,
tests/python/randgen.py, tests/python/relabel.py,
tests/python/remfin.py, tests/python/removeap.py,
tests/python/rs_like.py, tests/python/satmin.py,
tests/python/sbacc.py, tests/python/sccfilter.py,
tests/python/sccinfo.py, tests/python/sccsplit.py,
tests/python/semidet.py, tests/python/setacc.py,
tests/python/setxor.py, tests/python/simplacc.py,
tests/python/simstate.py, tests/python/sonf.py, tests/python/split.py,
tests/python/streett_totgba.py, tests/python/streett_totgba2.py,
tests/python/stutter.py, tests/python/sum.py,
tests/python/synthesis.py, tests/python/toparity.py,
tests/python/toweak.py, tests/python/tra2tba.py,
tests/python/trival.py, tests/python/twagraph.py,
tests/python/zlktree.py: Replace all occurrences of "assert" by calls
to unittest.TestCase methods.

tests/python/alternating.py

@@ -1,7 +1,7 @@
 #!/usr/bin/python3
 # -*- mode: python; coding: utf-8 -*-
-# Copyright (C) 2016, 2017, 2021 Laboratoire de Recherche et Développement de
-# l'EPITA.
+# Copyright (C) 2016-2017, 2021-2022 Laboratoire de Recherche
+# et Développement de l'EPITA.
 #
 # This file is part of Spot, a model checking library.
 #
@@ -20,6 +20,8 @@
 
 import spot
 import buddy
+from unittest import TestCase
+tc = TestCase()
 
 aut = spot.make_twa_graph(spot._bdd_dict)
 
@@ -38,9 +40,8 @@ aut.new_edge(2, 2, p1 | p2)
 
 tr = [(s, [[x for x in aut.univ_dests(i)] for i in aut.out(s)])
       for s in range(3)]
-print(tr)
-assert [(0, [[1, 2], [0, 1]]), (1, [[0, 2, 1]]), (2, [[2]])] == tr
-assert not aut.is_existential()
+tc.assertEqual([(0, [[1, 2], [0, 1]]), (1, [[0, 2, 1]]), (2, [[2]])], tr)
+tc.assertFalse(aut.is_existential())
 
 received = False
 try:
@@ -49,11 +50,10 @@ try:
             pass
 except RuntimeError:
     received = True
-assert received
+tc.assertTrue(received)
 
 h = aut.to_str('hoa')
-print(h)
-assert h == """HOA: v1
+tc.assertEqual(h, """HOA: v1
 States: 3
 Start: 0
 AP: 2 "p1" "p2"
@@ -68,22 +68,20 @@ State: 1
 [0&1] 0&2&1
 State: 2
 [0 | 1] 2
---END--"""
+--END--""")
 
 aut2 = spot.automaton(h)
 h2 = aut2.to_str('hoa')
-print(h2)
-assert h != h2
+tc.assertNotEqual(h, h2)
 
 # This will sort destination groups
 aut.merge_univ_dests()
 h = aut.to_str('hoa')
-assert h == h2
+tc.assertEqual(h, h2)
 
 aut2.set_univ_init_state([0, 1])
 h3 = aut2.to_str('hoa')
-print(h3)
-assert h3 == """HOA: v1
+tc.assertEqual(h3, """HOA: v1
 States: 3
 Start: 0&1
 AP: 2 "p1" "p2"
@@ -98,23 +96,22 @@ State: 1
 [0&1] 0&1&2
 State: 2
 [0 | 1] 2
---END--"""
+--END--""")
 
 st = spot.states_and(aut, [0, 2])
 st2 = spot.states_and(aut, [1, st])
 st3 = spot.states_and(aut, [0, 1, 2])
-assert (st, st2, st3) == (3, 4, 5)
+tc.assertEqual((st, st2, st3), (3, 4, 5))
 
 received = False
 try:
     st4 = spot.states_and(aut, [])
 except RuntimeError:
     received = True
-assert received
+tc.assertTrue(received)
 
 h = aut.to_str('hoa')
-print(h)
-assert h == """HOA: v1
+tc.assertEqual(h, """HOA: v1
 States: 6
 Start: 0
 AP: 2 "p1" "p2"
@@ -136,11 +133,10 @@ State: 4
 [0&1] 0&1&2
 State: 5
 [0&1] 0&1&2
---END--"""
+--END--""")
 
 h = spot.split_edges(aut).to_str('hoa')
-print(h)
-assert h == """HOA: v1
+tc.assertEqual(h, """HOA: v1
 States: 6
 Start: 0
 AP: 2 "p1" "p2"
@@ -168,7 +164,7 @@ State: 4
 [0&1] 0&1&2
 State: 5
 [0&1] 0&1&2
---END--"""
+--END--""")
 
 
 # remove_univ_otf
@@ -206,11 +202,11 @@ State: 2
 --END--"""
 
 desalt = spot.remove_univ_otf(aut)
-assert(desalt.to_str('hoa') == out)
+tc.assertEqual(desalt.to_str('hoa'), out)
 
-assert aut.num_states() == 3
-assert aut.num_edges() == 3
+tc.assertEqual(aut.num_states(), 3)
+tc.assertEqual(aut.num_edges(), 3)
 aut.edge_storage(3).cond = buddy.bddfalse
 aut.purge_dead_states()
-assert aut.num_states() == 1
-assert aut.num_edges() == 0
+tc.assertEqual(aut.num_states(), 1)
+tc.assertEqual(aut.num_edges(), 0)