CompensateBoundaryEventBehavior.js: fail 'shape.replace' event handler when the targetElement is undefined

[Vovamzur]

Describe the Bug

There is a bug while using bpmn-js-element-templates with bpmn-js@16.3.0 after removing an element template:

EventBus.js:437 unhandled error in event listener TypeError: Cannot read properties of undefined (reading 'type')
    at handleReplacement (CompensateBoundaryEventBehavior.js:101:1)

It is caused by calling https://github.com/bpmn-io/bpmn-js-element-templates/blob/main/src/element-templates/cmd/RemoveElementTemplateHandler.js#L46 without hints.targetElement

As we can see from line https://github.com/bpmn-io/bpmn-js/blob/develop/lib/features/modeling/behavior/CompensateBoundaryEventBehavior.js#L95 the targetElement could be undefined.

As solution, we could check it for undefined before getting properties like targetElement.type or targetElement.eventDefinitionType on 100,101,115 lines

Steps to Reproduce

1. apply some element template
2. remove element template

Expected Behavior

Element template is removed without errors

Environment

• Library version: 16.3.1
• bpmn-js-element-templates: 1.10.0

[nikku]

I can reproduce this in the bpmn-js-element-templates test environment:

• spin it up using npm start
• assign an element template to a compensation activity
• remove element template from a compensation activity

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[nikku]

We see these failures when updating the element template repository dependencies, too: bpmn-io/bpmn-js-element-templates#40

[barmac]

This sounds critical :/

[barmac]

I had a closer look, and in the compensation PR I assumed that targetElement is set but it's only done when replacing via bpmnReplace. We should probably look at the newData property instead as it's set in the core diagram-js component.

[barmac]

Closed via #2074