def test_lazy_loading(tmp_path):
s = BaseSignal(np.empty((5, 5, 5)))
fname = tmp_path / 'tmp.hdf5'
s.save(fname, overwrite=True)
shape = (10000, 10000, 100)
del s
f = h5py.File(fname, mode='r+')
s = f['Experiments/__unnamed__']
del s['data']
s.create_dataset('data', shape=shape, dtype='float64', chunks=True)
f.close()
s = load(fname, lazy=True)
assert shape == s.data.shape
assert isinstance(s.data, da.Array)
assert s._lazy
s.close_file()
