Support changing images in ImageEditor for all IImage subclasses

[corranwebster]

Currently code is doing a check for ImageResource. Includes smoke tests for expected functionality.

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[aaronayres35]

Generally changes LGTM, but I'm not sure why we're only testing on wx / I'm seeing test failures locally

[aaronayres35]

why can't these be run on Qt?

[aaronayres35]

The CI currently only runs on Qt.

Locally I ran python etstool.py install --toolkit=wx, edm shell -e traitsui-test-3.6-wx and python -m unittest traitsui.tests.editors.test_image_editor and I see the following test failures:

======================================================================
ERROR: test_image_editor_none (traitsui.tests.editors.test_image_editor.TestImageEditor)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/tests/editors/test_image_editor.py", line 141, in test_image_editor_none
    with create_ui(obj1, dict(view=view)) as ui:
  File "/Users/aayres/.edm/envs/traitsui-test-3.6-wx/lib/python3.6/contextlib.py", line 81, in __enter__
    return next(self.gen)
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/testing/tester/ui_tester.py", line 105, in create_ui
    ui = object.edit_traits(**ui_kwargs)
  File "/Users/aayres/.edm/envs/traitsui-test-3.6-wx/lib/python3.6/site-packages/traits/has_traits.py", line 1830, in edit_traits
    args,
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/view.py", line 450, in ui
    ui.ui(parent, kind)
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/ui.py", line 235, in ui
    self.rebuild(self, parent)
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/wx/toolkit.py", line 118, in ui_live
    ui_live.ui_live(ui, parent)
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/wx/ui_live.py", line 47, in ui_live
    _ui_dialog(ui, parent, BaseDialog.NONMODAL)
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/wx/ui_live.py", line 81, in _ui_dialog
    BaseDialog.display_ui(ui, parent, style)
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/wx/ui_base.py", line 61, in display_ui
    ui.owner.init(ui, parent, style)
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/wx/ui_live.py", line 195, in init
    sw = panel(ui, window)
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/wx/ui_panel.py", line 266, in panel
    panel, content[0], ui
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/wx/ui_panel.py", line 423, in fill_panel_for_group
    panel, group, ui, suppress_label, is_dock_window, create_panel
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/wx/ui_panel.py", line 577, in __init__
    self.add_items(content, panel, self.sizer)
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/wx/ui_panel.py", line 932, in add_items
    editor.prepare(item_panel)
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/editor.py", line 247, in prepare
    self.init(parent)
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/wx/image_editor.py", line 44, in init
    self.control = ImageControl(parent, convert_bitmap(image), padding=0)
  File "/Users/aayres/.edm/envs/traitsui-test-3.6-wx/lib/python3.6/site-packages/pyface/ui_traits.py", line 92, in convert_bitmap
    return image.create_bitmap()
AttributeError: 'NoneType' object has no attribute 'create_bitmap'

======================================================================
ERROR: test_image_editor_resource (traitsui.tests.editors.test_image_editor.TestImageEditor)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/tests/editors/test_image_editor.py", line 62, in test_image_editor_resource
    image=ImageResource(absolute_path=filename1)
TypeError: __init__() got an unexpected keyword argument 'absolute_path'

======================================================================
ERROR: test_image_editor_static (traitsui.tests.editors.test_image_editor.TestImageEditor)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/aayres/Desktop/all_ets/traitsui/traitsui/tests/editors/test_image_editor.py", line 51, in test_image_editor_static
    image=ImageResource(absolute_path=filename1),
TypeError: __init__() got an unexpected keyword argument 'absolute_path'

----------------------------------------------------------------------
Ran 5 tests in 1.216s

FAILED (errors=3)

running with pyside2 I see the same failures. In pyface.i_image_resource.MImageResource the __init__ method is overridden and doesn't call super.

[corranwebster]

This should now be resolved. The absolute_path was me misremembering the API, not a bug in Pyface.

[aaronayres35]

LGTM and all tests seem to be passing 🙌 (although Test with EDM / test-with-edm (macos-latest, pyside2) (pull_request) is being skipped on this PR and I'm not sure why 😕 - https://github.com/enthought/traitsui/runs/5230631738?check_suite_focus=true isn't very helpful)

[corranwebster]

Re-ran the tests and all are passing, no skips.