def test_intvar_update():
f = Frame()
intv = IntVar(f, 1.)
def dx(f):
return 1.
intv.updater = dx
assert intv.update() == None
assert intv == 1.
def test_intvar_snapshots():
f = Frame()
intv = IntVar(f, 2.1)
with pytest.raises(ValueError):
intv.snapshots = [2., 1.]
with pytest.raises(ValueError):
intv.snapshots = [1., 1.]
def dx(x):
return 1.
intv.updater = dx
intv.snapshots = []
with pytest.raises(ValueError):
intv.nextsnapshot
with pytest.raises(ValueError):
intv.prevsnapshot
intv.snapshots = [1., 2., 3.]
assert intv.nextsnapshot == 3.
assert intv.prevsnapshot == 2.