Cannot delete a "parent" relation in the extension modeler about ecore

[philippemerle]

Hi William,
Is this a feature of Sirius or a bug of Sirius?

[wpiers]

Not really a bug : deletion is supported for Nodes by default, or for Element based edges, but Relation based edges like "parent" "applies" & "depend" a Delete tool must be defined.
I did it for those references in commit a297712

It can be used as example for other designs if necessary. Below is the raw xmi for a relation deletion tool (without eOpposite) :

<ownedTools xsi:type="tool:DeleteElementDescription" name="Delete<FEATURE_NAME>">
    <element name="element"/>
    <elementView name="elementView"/>
    <containerView name="containerView"/>
    <initialOperation>
        <firstModelOperations xsi:type="tool_1:Unset" featureName="<FEATURE_NAME>" 
        elementExpression="[elementView.targetNode.oclAsType(DSemanticDecorator).target/]"/>
    </initialOperation>
</ownedTools>