[Vm-dev] Finding pointers via heap walking and contexts

[Eliot Miranda]

On Thu, Aug 29, 2013 at 8:54 AM, Igor Stasenko <siguctua at gmail.com> wrote:

>
> Hello,
>
> i tried to implement a simple algorithm to find nearest common roots for
> some object(s)..
> see the attached code.
>
> The problem i discovered that the last assertion of my test fails:
> =====
> testArrayShouldBeRootOfItsElements
>
>     | obj1 obj2 array arrayToTest roots |
>
>     obj1 := 'ObjectA' copy.
>     obj2 := 'ObjectB' copy.
>
>     array := {  obj1. obj2 }.
>     arrayToTest := { obj1. obj2 }.
>
>     roots := CommonRootsFinder new findCommonRootsOf:  arrayToTest.
>
>     self assert: (roots identityIncludes: array).
>     self assert: (roots identityIncludes: arrayToTest) not.
>     self assert: (roots identityIncludes: thisContext).  "- sometimes
> works , sometimes not "
> ========
>
> but, when i restart the method in debugger and step down through it,
> assertion DOES NOT fails.
> This means that memory scan does not reveals this context as it should be.
>
> (maybe because it stops at the object which located before location of
> thisContext)?
>

That would make sense.  For debugging, why don't you record the objects
visited in an OrderedCollection, and then you can look at what order the
pointer finder found them.


>
> any suggestions/comments/ideas , how to make sure that assert will never
> fail?
>

Doesn't that depend on how you've implemented CommonRootsFinder?


> --
> Best regards,
> Igor Stasenko.
>
>


-- 
best,
Eliot
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