ButtonView keystroke error

[maziyank]

I experienced an error with CKEditor with my custom plugin after updating CKEditor to v 26.0.0

TypeError: Cannot read property 'map' of undefined
    at parseKeystroke (keyboard.js:109)
    at getEnvKeystrokeText (keyboard.js:121)
    at TemplateToBinding.callback (buttonview.js:270)
    at TemplateToBinding.getValue (template.js:908)
    at template.js:1038
    at Array.map (<anonymous>)
    at getValueSchemaValue (template.js:1035)
    at syncValueSchemaValue (template.js:1053)
    at Template._bindToObservable (template.js:783)
    at Template._renderText (template.js:477)
(anonymous) @ app.js:19
Promise.catch (async)
./app.js @ app.js:18
__webpack_require__ @ bootstrap:19
(anonymous) @ bootstrap:83
(anonymous) @ bootstrap:83

This happened because I unconsciously created a button view with arg withKeystroke=true and forget to define keystroke.

editor.ui.componentFactory.add( 'customPlugin', locale => {
            const view = new ButtonView( locale );
            view.set( {
                label: 'Custom Plugin',
                icon: someIcon,
                tooltip: true,
                withKeystroke : true
            } );

            return view;
        } );

On CKEditor 25.0.0 this works fine but in CKEditor 26.0.0+ this causes the error.

[mlewand]

@ckeditor/qa-team can you verify that it is a regression as mentioned in the issue and add a label in case it is?

[mlewand]

I'm hesitant whether it's a dx or ux squad issue. Given that it happens in case of incomplete dev configuration I say it's more of a DX thing.

[FilipTokarski]

In 25.0.0 I got:

TypeError: Cannot read property 'split' of undefined
    at splitKeystrokeText (keyboard.js:234)
    at getEnvKeystrokeText (keyboard.js:115)
    at TemplateToBinding.callback (buttonview.js:270)
    at TemplateToBinding.getValue (template.js:908)
    at template.js:1038
    at Array.map (<anonymous>)
    at getValueSchemaValue (template.js:1035)
    at syncValueSchemaValue (template.js:1053)
    at Template._bindToObservable (template.js:783)
    at Template._renderText (template.js:477)