def test_count():
r = TopicsRegistry()
t1 = Topic('test1')
r.register(t1)
assert r.count() == 1
t2 = Topic('test2')
t3 = Topic('test3')
r.register(t2)
r.register(t3)
assert r.count() == 3
def test_register():
r = TopicsRegistry()
t = Topic('test')
r.register(t)
assert r.count() == 1
# registering the same topic multiple times won't change it
r.register(t)
assert r.count() == 1
# ... but a new one, will
t2 = Topic('test2')
r.register(t2)
assert r.count() == 2