code: def test_vectorfield_linear_color_op(self):
      vectorfield = VectorField(
          [(0, 0, 0, 1, 0), (0, 1, 0, 1, 1), (0, 2, 0, 1, 2)],
          vdims=["A", "M", "color"],
      ).opts(color="color")
      plot = bokeh_renderer.get_plot(vectorfield)
      cds = plot.handles["cds"]
      glyph = plot.handles["glyph"]
      cmapper = plot.handles["color_color_mapper"]
      self.assertTrue(cmapper, LinearColorMapper)
      self.assertEqual(cmapper.low, 0)
      self.assertEqual(cmapper.high, 2)
      self.assertEqual(
          cds.data["color"], np.array([0, 1, 2, 0, 1, 2, 0, 1, 2])
      )
      self.assertEqual(
          property_to_dict(glyph.line_color),
          {"field": "color", "transform": cmapper},
      )
  
file_path: holoviews/holoviews/tests/plotting/bokeh/test_vectorfieldplot.py
imports: import numpy
  from holoviews.element import VectorField
  from holoviews.plotting.bokeh.util import property_to_dict
  from ..utils import ParamLogStream
  from .test_plot import TestBokehPlot, bokeh_renderer
label_desc: Use image node_id 2 for calling the TestVectorFieldPlot obj's underlying member method code with example usage: obj.test_vectorfield_linear_color_op() without return types