[squeak-dev] Installing metacello within a 'Smalltalk run:[]' fails

Levente Uzonyi leves at caesar.elte.hu
Thu Jul 16 02:09:40 UTC 2020

On Wed, 15 Jul 2020, tim Rowledge wrote:

> Running 
> Installer ensureRecentMetacello 
> works. (in a 5.3-19435 image)
> Wrapping it in 
> Smalltalk run:[Installer ensureRecentMetacello ]
> crashes. Specifically in MetacelloScriptEngine>>#lookupProjectSpecFor: we find that 'registration' is nil on the last line. 
> Seems a bit odd; possibly sometihng to do with the assorted exception handling in the SmalltalkImage>run: code?

I think the cause of the problem is that SmalltalkImage >> #run: 
catches all Notifications, logs them, and finally #resumes them.
But many Notifications override #defaultAction, and the return value of 
that method will be the value the Notification normally returns with when 
not handled.
#resume does not send #defaultAction (it sends #defaultResumeValue, 
which is rarely used).

IMO the code should not #resume the Notifications just #pass them, so that 
they can return with whatever they want (or be handled by an outer 


> I'm trying to make a simplecommandline  filein that will load a bunch'o'stuff, something that has been doable before, so this is a bit puzzling.
> {a bit later}
> Hmm, moving the Installer ensureRecentMetacello  outside the run: block lets it install but later use of metacello within the run: block to load Seaside fails because MetacelloIgnorePackageLoaded signal: pkg doesn't return a boolean. So, yeah, probably sometihng to do with the run: handling of exceptions.
> tim
> --
> tim Rowledge; tim at rowledge.org; http://www.rowledge.org/tim
> "How many tnuctip does it take to change a lightbulb?” 
> "Depends what you want them to change it into."

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