ScatterInspector does not deselect all on index == None

[amalec]

I've been playing around with the scattertoggle.py example. Maybe I'm missing something, but the ScatterInspector seems to fail to deselect all points when clicking on whitespace on the plot (that is, index == None). Something along the lines of this seems to fix it.

class PatchedScatterInspector(ScatterInspector):
        def _deselect(self, index=None):
            plot = self.component
            if index:
                super(PatchedScatterInspector, self)._deselect(index)
            else:
                for name in ('index', 'value'):
                    if not hasattr(plot, name):
                        continue
                    md = getattr(plot, name).metadata
                    md[self.selection_metadata_name] = []
                    getattr(plot, name).metadata_changed = True
            return

Cheers,

-A

[notmatthancock]

I just ran into this because the docstring for ScatterInspector._deselect claims that selection clearing should occur when index=None.

Here's a MWE of the bug:

from chaco.api import *
from chaco.tools.api import *
from enable.api import ComponentEditor
from traits.api import *
from traitsui.api import *

import numpy as np


class MyInspector(ScatterInspector):

    def normal_key_pressed(self, event):
        if event.character == 'Esc':
            # Should clear all selections, but does not!
            self._deselect()


class Demo(HasTraits):

    plot = Instance(Plot)
    data = Instance(ArrayPlotData)

    def _data_default(self):
        return ArrayPlotData(
            x=np.linspace(0, 1, 11),
            y=np.linspace(0, 1, 11) + 0.1*np.random.randn(11)
        )

    def _plot_default(self):
        plot = Plot(self.data)
        scatter = plot.plot(('x', 'y'), type='scatter')[0]
        tool = MyInspector(scatter)
        scatter.tools.append(tool)
        return plot

    def default_traits_view(self):
        return View(
            UItem('plot', editor=ComponentEditor()),
            resizable=True,
        )

Demo().configure_traits()