Thanks Levente,

Indeed that is a much simpler solution. The fact that the selector refers
to "hashBlock" and "equalBlock" should have been a clue, thank you for
pointing it out.

Should I revert the changes? In testPerformIdentityEquals I wrote this:

	"Selector #== must refer to aProtoObj, not to the MCPackage to which it delegates"
	self assert: [aProtoObj perform: #== with: aProtoObj]
		description: 'If aProtoObj delegates to the MCPackage the identity test will fail'.

because I expected that identity test should always refer to the actual receiver
object, but maybe that is no the right assumption in the case of proxies.

Dave


On Mon, May 14, 2018 at 01:52:14AM +0200, Levente Uzonyi wrote:
> Having a look at the code, it's probably enough to change 
> #newLargeIdentityDictionaryOfSize: to be
> 
> 	^(PluggableDictionary new: size)
> 		hashBlock: [ :object | object largeHash ];
> 		equalBlock: [ :a :b | a == b ];
> 		yourself
> 
> That change should also make the code somewhat faster.
> 
> Levente
> 
> On Mon, 14 May 2018, Levente Uzonyi wrote:
> 
> >Hi Dave,
> >
> >I think the best would be if SystemTracer used the mirror primitives (See 
> >Context's mirror primitives method category), primitive 110 
> >(#object:eqeq:) in this case, so that proxies like MCPackageInEnvironment 
> >can't affect it.
> >
> >Levente
> >
> >On Sun, 13 May 2018, David T. Lewis wrote:
> >
> >>This update feels a bit hacky to me with its test for a specific 
> >>selector, 
> >so
> >>better or clearer solutions are welcome. Meanwhile, the prior behavior was
> >>corrupting identity dictionaries, which seems like a Bad Thing, so I put
> >>this fix (along with a new unit test) directly into trunk.
> >>
> >>The problem showed up as I was trying to get SystemTracer64 working again 
> >on
> >>V3 images, so it was not an easy thing to debug :-/
> >>
> >>Dave
> >>
> >>On Sun, May 13, 2018 at 11:14:39PM +0000, commits at source.squeak.org wrote:
> >>>David T. Lewis uploaded a new version of Monticello to project The Trunk:
> >>>http://source.squeak.org/trunk/Monticello-dtl.682.mcz
> >>>
> >>>==================== Summary ====================
> >>>
> >>>Name: Monticello-dtl.682
> >>>Author: dtl
> >>>Time: 13 May 2018, 7:14:27.068827 pm
> >>>UUID: 76fc84e6-7e2b-4a6a-af6b-2d02d11c38eb
> >>>Ancestors: Monticello-nice.681
> >>>
> >>>Sending perform: #== with: anObject to an instance of 
> >MCPackageInEnvironment should test identity of the actual instance, not 
> >the MCPackage to which it refers. If this is not so, a PluggableDictionary 
> >will fail when doing identity checks on its keys, as is the case for a 
> >SystemTracer adding all objects to its oop dictionary.
> >>>
> >>>Implement MCPackageInEnvironment>>perform:with: such that performing #== 
> >will call primitivePerform, and all other selectors are delegated to the 
> >MCPackage as before.
> >>>
> >>>=============== Diff against Monticello-nice.681 ===============
> >>>
> >>>Item was added:
> >>>+ ----- Method: MCPackageInEnvironment>>perform:with: (in category 
> >'delegating') -----
> >>>+ perform: aSymbol with: anObject
> >>>+ 	"If aSymbol is #== then the sender is trying to perform an identity 
> >comparison.
> >>>+ 	This cannot be delegated, because the delegate will be a different 
> >object.
> >>>+ 	Implement perform:with: here to protect for this case. An important 
> >example
> >>>+ 	is the case of PluggableDictionary, which relies on perform:with: to 
> >implement
> >>>+ 	comparisons for an identity dictionary."
> >>>+ 
> >>>+ 	aSymbol == #==
> >>>+ 		ifTrue: [ ^self privatePerform: aSymbol with: anObject ]
> >>>+ 		ifFalse: [ ^package perform: aSymbol with: anObject "as per 
> >doesNotUnderStand:" ]
> >>>+ !
> >>>
> >>>Item was added:
> >>>+ ----- Method: MCPackageInEnvironment>>privatePerform:with: (in 
> >>>category 
> >'delegating') -----
> >>>+ privatePerform: aSymbol with: anObject
> >>>+ 	"aSymbol is #== and the sender is trying to perform an identity 
> >comparison.
> >>>+ 	Invoke primitivePerform."
> >>>+ 
> >>>+ 	<primitive: 83>
> >>>+ 	^ self primitiveFailed!
> >>>
> >>>
> >
> >
>