class JS:
parent = event.prop(parent)
@event.connect('parent')
def on_parent(self, *events):
parent = events[-1].new_value
parent_id = 'None' if parent is None else parent._id
print('parent of %s changed to %s in JS' % (self._id, parent_id))
class Node(app.Model):
parent = event.prop(parent)
@event.connect('parent')
def on_parent(self, *events):
parent = events[-1].new_value
parent_id = 'None' if parent is None else parent._id
print('parent of %s changed to %s in Py' % (self._id, parent_id))
class Both:
# cannot define parent prop here; it would result in an infinite loop
@event.prop
def children(self, new_children=()):
old_children = self.children
if not old_children: # Can be None during initialization
old_children = []
for child in old_children:
if child not in new_children:
child.parent = None
for child in new_children:
if child not in old_children:
child.parent = self
return tuple(new_children)
class JS:
parent = event.prop(parent)
@event.connect('parent')
def on_parent(self, *events):
parent = events[-1].new_value
parent_id = 'None' if parent is None else parent._id
print('parent of %s changed to %s in JS' % (self._id, parent_id))
def test_property():
class MyObject(event.HasEvents):
@event.prop
def foo(self, v=1.2):
return float(v)
@event.prop
def bar(self, v=1.3):
return float(v)
m = MyObject()
assert m.foo == 1.2
assert m.bar == 1.3
m = MyObject(foo=3)
assert m.foo == 3.0
m.foo = 5.1
m.bar = 5.1
assert m.foo == 5.1
assert m.bar == 5.1
m.foo = '9.3'
assert m.foo == 9.3
m = MyObject(foo=3)
assert m.foo == 3.0
# Hacky, but works
def foo():
pass
x = event.prop(foo)
assert 'foo' in repr(x)
spam = lambda x:None
x = event.prop(spam)
assert '<lambda>' in repr(x)
# fails
with raises(ValueError):
m.foo = 'bla'
with raises(ValueError):
MyObject(foo='bla')
with raises(TypeError):
m._set_prop(3, 3) # Property name must be a string
with raises(AttributeError):
m._set_prop('spam', 3) # MyObject has not spam property
with raises(AttributeError):
MyObject(spam='bla') # MyObject has not spam property
with raises(TypeError):
event.prop(3) # prop decorator needs callable
with raises(AttributeError):
del m.foo # cannot delete a property
class MyObject2(event.HasEvents):
@event.prop
def foo(self, v):
return float(v)
#with raises(RuntimeError):
# MyObject2() # no default value for foo
ob = MyObject2()
assert ob.foo is None