def test_simple_reduce(self):
s = Substitution()
# variables ending with '#N' are considered as renamed
s['A#0'] = Variable('I')
s['I'] = Atomic('p')
s['X'] = Variable('C#0')
result = Substitution()
result['I'] = Atomic('p')
s.reduce()
self.assertEquals(result, s)
def test_reduce_with_compound(self):
s = Substitution()
# variables ending with '#N' are considered as renamed
s['A#0'] = Variable('I')
s['B'] = Compound('p', Variable('A#0'))
s['I'] = Atomic('q')
result = Substitution()
result['I'] = Atomic('q')
result['B'] = Compound('p', Variable('A#0'))
s.reduce()
self.assertEquals(result, s)
def test_simple_flatten(self):
s = Substitution()
s['A'] = Variable('B')
s['B'] = Atomic(1)
self.assertEquals(Variable('B'), s.get('A'))
s.flatten()
self.assertEquals(Atomic(1), s.get('A'))
self.assertEquals(Atomic(1), s['B'])
def test_update(self):
s1 = Substitution()
s1['A'] = Variable('B')
s1['B'] = Atomic(1)
s2 = Substitution()
s2['A'] = Variable('C')
s2['D'] = Atomic(2)
s1.update(s2)
b = s1.get('A')
# A is still bound to a variable...
self.assertTrue(isinstance(b, Variable))
# ...but the variable has been updated to point to 1
self.assertEquals(Atomic(1), b.value)
# C is updated to reflect its proper status
self.assertEquals(Atomic(1), s1['C'])
# D is left as it is
self.assertEquals(Atomic(2), s1['D'])
def test_get_binding(self):
s = Substitution()
s['A'] = Variable('B')
s['B'] = Atomic(1)
self.assertEquals(Atomic(1), s['A'])
self.assertEquals(Atomic(1), s['B'])
def test_empty_semantics(self):
s = Substitution()
self.assertFalse(s)
def test_flatten_with_compound(self):
s = Substitution()
s['A'] = Variable('I')
s['B'] = Compound('p', Variable('A'))
s.flatten()
self.assertEquals(Compound('p', Variable('I')), s['B'])
def test_set_existing_binding(self):
s = Substitution()
s['A'] = Atomic(1)
s['A'] = Atomic(2)
self.assertEquals(Atomic(1), s['A'])