Implement debugger extensions like in StateSpecs-GTTools

[dionisiydk]

Sadly NewTools does not provide any hooks to extend debugger to support new kind of assertion failures. Only basic #assert: logic is supported with very primitive variable analysis:

Context>>findFailedAssertionContextInSenderChain

	^ (self findContextSuchThat: [ :ctx | 
		   (ctx hasTemporaryVariableNamed: #actual) and: [ 
			   ctx hasTemporaryVariableNamed: #expected ] ]) ifNil: [ 
		  StDebuggeAssertionFailureContextNotFound new signal ]

which is used from:

StDebuggerInspector>>updateLayoutForContexts: aContext isAssertionFailure: isTopContextFailingAssertion

	| assertionResult |
	isTopContextFailingAssertion ifFalse: [ 
		currentLayoutSelector = self defaultLayoutSelector ifTrue: [ ^ self ].
		self setDefaultLayout.
		^self ].
	currentLayoutSelector = self assertionLayoutSelector ifTrue: [ ^ self ].

	[ assertionResult := aContext findFailedAssertionResultsInSenderChain ]
		on: StDebuggeAssertionFailureContextNotFound
		do: [ self setDefaultLayout.
			^self ].		
	
	assertionFailure := StFailingAssertionInspector
		                    diffInspectorsFromActual: assertionResult actual
		                    expected: assertionResult expected
		                    application: self application.
	self setAssertionLayout

It should really lookup the exception and ask exception instance to setup the inspector extension. This requires contribution into NewTools project