code: def test_spread_stream_data(self):
      buffer = Buffer(
          {"y": np.array([]), "yerror": np.array([]), "x": np.array([])}
      )
      dmap = DynamicMap(Spread, streams=[buffer])
      plot = bokeh_renderer.get_plot(dmap)
      buffer.send(
          {
              "y": [1, 2, 1, 4],
              "yerror": [0.5, 0.2, 0.1, 0.5],
              "x": [0, 1, 2, 3],
          }
      )
      cds = plot.handles["cds"]
      self.assertEqual(
          cds.data["x"],
          np.array([0.0, 1.0, 2.0, 3.0, 3.0, 2.0, 1.0, 0.0]),
      )
      self.assertEqual(
          cds.data["y"],
          np.array([0.5, 1.8, 0.9, 3.5, 4.5, 1.1, 2.2, 1.5]),
      )
  
file_path: holoviews/holoviews/tests/plotting/bokeh/test_spreadplot.py
imports: import numpy
  from holoviews.core.spaces import DynamicMap
  from holoviews.element import Spread
  from holoviews.streams import Buffer
  from .test_plot import TestBokehPlot, bokeh_renderer
label_desc: Use image node_id 1 for calling the TestSpreadPlot obj's underlying member method code with example usage: obj.test_spread_stream_data() without return types