def test_solve_nested_clause2(self):
src = '''
male(zeus).
male(chronos).
female(rhea).
female(athena).
parent(zeus, chronos).
parent(zeus, rhea).
parent(athena, zeus).
father(X, Y) :- parent(X, Y), male(Y).
grandfather(X, Z) :- parent(X, Y), father(Y, Z).
?- grandfather(X, Z).
'''
db = parser.parse(src)
gen = solve(db.rules, db.queries[0])
# Assertions
exp = {
'X': ('var', 'X_0'),
'X_0': ('term', 'athena', []),
'X_1': ('term', 'zeus', []),
'Y_0': ('term', 'zeus', []),
'Y_1': ('var', 'Z_0'),
'Z': ('var', 'Z_0'),
'Z_0': ('term', 'chronos', []),
}
self.assertEqual(next(gen), exp)
exp = None
self.assertEqual(next(gen), exp)
def test_solve_double_clause2(self):
src = '''
parent(zeus, chronos).
parent(zeus, rhea).
parent(athena, zeus).
grandparent(X, Y) :- parent(X, Z), parent(Z, Y).
?- grandparent(X, Y).
'''
db = parser.parse(src)
gen = solve(db.rules, db.queries[0])
# Assertions
exp = {
'X': ('var', 'X_0'),
'X_0': ('term', 'athena', []),
'Y': ('var', 'Y_0'),
'Y_0': ('term', 'chronos', []),
'Z_0': ('term', 'zeus', [])
}
self.assertEqual(next(gen), exp)
exp = {
'X': ('var', 'X_0'),
'X_0': ('term', 'athena', []),
'Y': ('var', 'Y_0'),
'Y_0': ('term', 'rhea', []),
'Z_0': ('term', 'zeus', [])
}
self.assertEqual(next(gen), exp)
def search(source):
global rules
prog = parser.parse(source)
rules += prog.rules
for query in prog.queries:
vs = vars(query)
for sol in solve(rules, query):
sol = compress(sol)
sol = restrict(sol, vs)
yield prettify(sol)
def test_solve_fail(self):
src = '''
human(sokrates).
human(plato).
god(zeus).
?- mortal(zeus).
'''
db = parser.parse(src)
gen = solve(db.rules, db.queries[0])
# Assertions
exp = None
self.assertEqual(next(gen), exp)
def test_solve_single_clause1(self):
src = '''
human(sokrates).
human(plato).
god(zeus).
mortal(X) :- human(X).
?- mortal(sokrates).
'''
db = parser.parse(src)
gen = solve(db.rules, db.queries[0])
# Assertions
exp = {'X_0': ('term', 'sokrates', [])}
self.assertEqual(next(gen), exp)
exp = None
self.assertEqual(next(gen), exp)
def test_solve_double_clause(self):
src = '''
human(sokrates).
deity(zeus).
male(sokrates).
male(zeus).
god(X) :- male(X), deity(X).
?- god(X).
'''
db = parser.parse(src)
gen = solve(db.rules, db.queries[0])
# Assertions
exp = {'X': ('var', 'X_0'), 'X_0': ('term', 'zeus', [])}
self.assertEqual(next(gen), exp)
exp = None
self.assertEqual(next(gen), exp)
def test_solve_facts_list(self):
src = '''
human(sokrates).
human(plato).
god(zeus).
?- human(X).
'''
db = parser.parse(src)
gen = solve(db.rules, db.queries[0])
# Assertions
exp = {'X': ('term', 'sokrates', [])}
self.assertEqual(next(gen), exp)
exp = {'X': ('term', 'plato', [])}
self.assertEqual(next(gen), exp)
exp = None
self.assertEqual(next(gen), exp)