Moving nested classes

[matthias-springer]

There should be a way to move a nested class from one parent to another parent, e.g. using drag and drop.

[abstraktor]

I'll give up for now. We need to look at this together or it's a waste of time. Leftovers:

• Cutting a class produces exceptions in the MethodView
• use ModuleSystemViewHelper canPaste to hide the paste button
• I don't know how to commit things

ModuleSystemViewHelper class>>canPaste
    ^cutSpec isNil not

ModuleSystemViewHelper class>>cut: aName from: aSpec 
    cutSpecName := aName.
    cutSpec := aSpec removeClassAt: aName

ModuleSystemViewHelper class>>pasteInto: aSpec 
    aSpec addClass: cutSpec name: cutSpecName.
    cutSpec := nil.
    cutSpecName := nil

SpecificationTest>>testAddClassName
    |spec added|
    added := ClassSpecification new.
    spec := ClassSpecification new.
    spec addClass: added name: 'added'.
    self assert: (spec classAt: 'added') equals: added.

SpecificationTest>>testRemoveClassAt
    |spec added|
    added := ClassSpecification new.
    spec := ClassSpecification new.
    spec addClass: added name: 'added'.
    self assert: (spec classAt: 'added') equals: added.

    self assert: (spec removeClassAt: 'added') equals: added.
    self assert: (spec classAt: 'added' ifAbsent: nil) equals: nil.

"ModuleSystemButtonBar"
[:memberSpecification | {
    #text -> 'Cut'.
    #icon -> UiSilkIcons cutIcon.
    #clicked -> [[
        ModuleSystemViewHelper cut: memberSpecification selector from: memberSpecification parent.
        ViEventNotifier trigger: #ModuleSystemModuleView]]}]

[:memberSpecification | {
    #text -> 'Paste Into'.
    #icon -> UiSilkIcons pastePlainIcon.
    #clicked -> [[
        ModuleSystemViewHelper pasteInto: memberSpecification.
        ViEventNotifier trigger: #ModuleSystemModuleView]]}]