Bug: Menu item enablement in CmUICommandDisplayStrategy>>#display:in:do: is fixed

[koendehondt]

Context : Pharo 12 and Pharo 13.

I think CmUICommandDisplayStrategy>>#display:in:do: is implemented incorrectly. Now it is:

display: aCmSpecCommand in: aMenuOrGroupPresenter do: aBlock
	aMenuOrGroupPresenter
		addItem: [ :item |
			aBlock value: item.
			item enabled: aCmSpecCommand canBeExecuted.
			item ]

As a consequence, a menu item's enablement state is set only once, when the menu item is added. Given that the command decides whether it can be executed, the enablement state should be updated every time a menu item is displayed. In Spec, that is achieved by passing a block to #enabled:.

So I think the method should be implemented as:

display: aCmSpecCommand in: aMenuOrGroupPresenter do: aBlock
	aMenuOrGroupPresenter
		addItem: [ :item |
			aBlock value: item.
			item enabled: [ aCmSpecCommand canBeExecuted ].
			item ]

This issue is related to #1559 and #1561, which report other enablement issues.