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[squeak-dev] OrderedCollection bug?

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Steven W Riggins

[squeak-dev] OrderedCollection bug?

Hi there!

We're running Sophie in a 3.8 image, and ran into a fairly nasty
OrderedCollection bug. I've not tried to replicate this in later
images.

o := OrderedCollection new.
o add: true beforeIndex: 2.

If you do this, the resulting collection is (nil)

No error, and true is not in the collection.

Can someone verify if this still exists, or what the proper behavior is?

Back Story: When "saving as" our page templates, the code determines
that some actions are not needed, but it still writes them into the
new collection based on their old index. So you end up with a nil
object in the collection, missing the object you intended to be there,
and a silent failure to boot.

We'll clean up our usage of OrderedCollection, but shouldn't this at
least throw an error?

Steve

Andreas.Raab

[squeak-dev] Re: OrderedCollection bug?

I've posted a fix at:

http://bugs.squeak.org/view.php?id=7121

Cheers,
- Andreas

Steven W Riggins wrote:

> Hi there!
>
> We're running Sophie in a 3.8 image, and ran into a fairly nasty
> OrderedCollection bug. I've not tried to replicate this in later images.
>
> o := OrderedCollection new.
> o add: true beforeIndex: 2.
>
> If you do this, the resulting collection is (nil)
>
> No error, and true is not in the collection.
>
> Can someone verify if this still exists, or what the proper behavior is?
>
> Back Story: When "saving as" our page templates, the code determines
> that some actions are not needed, but it still writes them into the new
> collection based on their old index. So you end up with a nil object in
> the collection, missing the object you intended to be there, and a
> silent failure to boot.
>
> We'll clean up our usage of OrderedCollection, but shouldn't this at
> least throw an error?
>
> Steve
>
>

timrowledge

Re: [squeak-dev] OrderedCollection bug?

In reply to this post by Steven W Riggins

Just as #add:before: raises an exception when the second arg is not in
the collection (indirectly, since #find: does not find the second arg)
add:beforeIndex: should raise an exception if there is no valid index
given as the second arg. Though to be honest I really don't think
OrderedCollection should even implement add:beforeIndex: &
add:afterIndex:. It's just.... yuck. All the usages I can spot are
simply poor algorithms that ought to be done properly.

tim
--
tim Rowledge; [hidden email]; http://www.rowledge.org/tim
Oxymorons: Act naturally

Steven W Riggins

Re: [squeak-dev] Re: OrderedCollection bug?

In reply to this post by Andreas.Raab

Thanks! Was along the lines I was looking at, but I was not sure of
the intended behavior.

On Jul 15, 2008, at 11:15 PM, Andreas Raab wrote:

> I've posted a fix at:
>
> http://bugs.squeak.org/view.php?id=7121
>
> Cheers,
> - Andreas
>
>
> Steven W Riggins wrote:
>> Hi there!
>> We're running Sophie in a 3.8 image, and ran into a fairly nasty
>> OrderedCollection bug. I've not tried to replicate this in later
>> images.
>> o := OrderedCollection new.
>> o add: true beforeIndex: 2.
>> If you do this, the resulting collection is (nil)
>> No error, and true is not in the collection.
>> Can someone verify if this still exists, or what the proper
>> behavior is?
>> Back Story: When "saving as" our page templates, the code
>> determines that some actions are not needed, but it still writes
>> them into the new collection based on their old index. So you end
>> up with a nil object in the collection, missing the object you
>> intended to be there, and a silent failure to boot.
>> We'll clean up our usage of OrderedCollection, but shouldn't this
>> at least throw an error?
>> Steve
>
>

Steven W Riggins

Re: [squeak-dev] OrderedCollection bug?

In reply to this post by timrowledge

Indeed. I suspect this is likely the issue. It was initially done
when something is cut out of a list, the undo can put it back. Likely
it should recall which object it was after, stick it back in and resort.

The bug we ran into was when adding an action, the action list was
empty, but a method synthesized a list composed of the frame and
template frame, which was not empty, so then it decided to insert
before index 3. That code has been changed to just do an add:

Steve

On Jul 15, 2008, at 11:24 PM, tim Rowledge wrote:

> Just as #add:before: raises an exception when the second arg is not
> in the collection (indirectly, since #find: does not find the second
> arg) add:beforeIndex: should raise an exception if there is no valid
> index given as the second arg. Though to be honest I really don't
> think OrderedCollection should even implement add:beforeIndex: &
> add:afterIndex:. It's just.... yuck. All the usages I can spot are
> simply poor algorithms that ought to be done properly.
>
> tim
> --
> tim Rowledge; [hidden email]; http://www.rowledge.org/tim
> Oxymorons: Act naturally
>
>
>