def test_weakref_event_emitter():
"""
We are testing that an event blocker does not keep hard reference to
the object we are blocking, especially if it's a bound method.
The reason it used to keep references is to get the count of how many time
a callback was blocked, but if the object does not exists, then the bound method
does not and thus there is no way to ask for it's count.
so we can keep only weak refs.
"""
e = EventEmitter(type='test_weak')
class Obj:
def cb(self):
pass
o = Obj()
ref_o = weakref.ref(o)
e.connect(o.cb)
#
with e.blocker(o.cb):
e()
del o
assert ref_o() is None
def test_error_on_connect():
"""Check that connections happen correctly even on decorated methods.
Some decorators will alter method.__name__, so that obj.method
will not be equal to getattr(obj, obj.method.__name__). We check here
that event binding will be correct even in these situations.
"""
def rename(newname):
def decorator(f):
f.__name__ = newname
return f
return decorator
class Test:
def __init__(self):
self.m1, self.m2, self.m4 = 0, 0, 0
@rename("nonexist")
def meth1(self, _event):
self.m1 += 1
@rename("meth1")
def meth2(self, _event):
self.m2 += 1
def meth3(self):
pass
def meth4(self, _event):
self.m4 += 1
t = Test()
e = EventEmitter(type="test")
e.connect(t.meth1)
e()
assert (t.m1, t.m2) == (1, 0)
e.connect(t.meth2)
e()
assert (t.m1, t.m2) == (2, 1)
meth = t.meth3
t.meth3 = "aaaa"
with pytest.raises(RuntimeError):
e.connect(meth)
e.connect(t.meth4)
assert t.m4 == 0
e()
assert t.m4 == 1
t.meth4 = None
with pytest.warns(RuntimeWarning, match="Problem with function"):
e()
assert t.m4 == 1
def test_event_blocker_count():
"""Test event emitter block counter with emission."""
e = EventEmitter(type="test")
with e.blocker() as block:
e()
e()
e()
assert block.count == 3
def test_disconnect_object():
count_list = []
def fun1():
count_list.append(1)
class TestOb:
call_list_1 = []
call_list_2 = []
def fun1(self):
self.call_list_1.append(1)
def fun2(self):
self.call_list_2.append(1)
t = TestOb()
e = EventEmitter(type="test")
e.connect(t.fun1)
e.connect(t.fun2)
e.connect(fun1)
e()
assert t.call_list_1 == [1]
assert t.call_list_2 == [1]
assert count_list == [1]
e.disconnect(t)
e()
assert t.call_list_1 == [1]
assert t.call_list_2 == [1]
assert count_list == [1, 1]
def test_weakref_event_emitter_cb(disconnect_and_should_be_none):
"""
Note that as above but with pure callback, We keep a reference to it, the
reason is that unlike with bound method, the callback may be a closure and
may not stick around.
We thus expect the wekref to be None only if explicitely disconnected
"""
e = EventEmitter(type='test_weak')
def cb(self):
pass
ref_cb = weakref.ref(cb)
e.connect(cb)
with e.blocker(cb):
e()
if disconnect_and_should_be_none:
e.disconnect(cb)
del cb
assert ref_cb() is None
else:
del cb
assert ref_cb() is not None
def test_event_order_methods():
res_li = []
class Test:
def fun1(self):
res_li.append(1)
def fun2(self):
res_li.append(2)
class Test2:
def fun3(self):
res_li.append(3)
def fun4(self):
res_li.append(4)
Test.__module__ = "napari.test.sample"
t1 = Test()
t2 = Test2()
e = EventEmitter(type="test")
e.connect(t1.fun1)
e.connect(t2.fun3)
e()
assert res_li == [1, 3]
res_li = []
e.connect(t1.fun2)
e.connect(t2.fun4)
e()
assert res_li == [2, 1, 4, 3]
def test_none_disconnect():
count_list = []
def fun1():
count_list.append(1)
def fun2(event):
count_list.append(2)
e = EventEmitter(type="test")
e.connect(fun1)
e()
assert count_list == [1]
e.disconnect(None)
e()
assert count_list == [1]
e.connect(fun2)
e()
assert count_list == [1, 2]
def test_to_many_positional():
class TestOb:
def fun(self, a, b, c=1):
pass
def simple_fun(a, b):
pass
t = TestOb()
e = EventEmitter(type="test")
with pytest.raises(RuntimeError):
e.connect(t.fun)
with pytest.raises(RuntimeError):
e.connect(simple_fun)
def test_weakref_disconnect():
class TestOb:
call_list_1 = []
def fun1(self):
self.call_list_1.append(1)
def fun2(self, event):
self.call_list_1.append(2)
t = TestOb()
e = EventEmitter(type="test")
e.connect(t.fun1)
e()
assert t.call_list_1 == [1]
e.disconnect((weakref.ref(t), "fun1"))
e()
assert t.call_list_1 == [1]
e.connect(t.fun2)
e()
assert t.call_list_1 == [1, 2]
def test_no_event_arg():
class TestOb:
def __init__(self):
self.count = 0
def fun(self):
self.count += 1
count = [0]
def simple_fun():
count[0] += 1
t = TestOb()
e = EventEmitter(type="test")
e.connect(t.fun)
e.connect(simple_fun)
e()
assert t.count == 1
assert count[0] == 1
def test_event_order_func():
res_li = []
def fun1():
res_li.append(1)
def fun2(val):
res_li.append(val)
def fun3():
res_li.append(3)
def fun4():
res_li.append(4)
def fun5(val):
res_li.append(val)
def fun6(val):
res_li.append(val)
fun1.__module__ = "napari.test.sample"
fun3.__module__ = "napari.test.sample"
fun5.__module__ = "napari.test.sample"
e = EventEmitter(type="test")
e.connect(fun1)
e.connect(partial(fun2, val=2))
e()
assert res_li == [1, 2]
res_li = []
e.connect(fun3)
e()
assert res_li == [3, 1, 2]
res_li = []
e.connect(fun4)
e()
assert res_li == [3, 1, 4, 2]
res_li = []
e.connect(partial(fun5, val=5), position="last")
e()
assert res_li == [3, 1, 5, 4, 2]
res_li = []
e.connect(partial(fun6, val=6), position="last")
e()
assert res_li == [3, 1, 5, 4, 2, 6]