Hey Jerome,

could you put the (sm) behind the name of the changeset in
the Subject?

that is, use

[FIX][BUG] BitmapFillGrabFormFix (sm)

BFAV has problems with the way you did it (they
don't show up correctly in the listing).

The easiest way is to just use the "mail changset to list"
option in the changesorter.

       Marcus

Am 15.03.2004 um 02:03 schrieb Peace Jerome:

> Problem: If a zero area form is grabbed problems
> arise. This fixes the problem when the user chooses to
> supply his own bitmap fill from the screen. This is a
> partial fix for a larger problem which I leave to the
> experts to choose a solution to.
>
>
> Form fromUser causes a lot of down the line problems.
>
> Most methods use the form supplied without checking to
> see if the user might have balked. If the corner is
> above or left of the origin fromUser returns an empty
> form with zero area.  Many down the line users assume
> all the forms they are given are valid. And crash in
> some horrible way if they aren't.
>
> e.g. Circle exampleTwo. will hang (at least it did for
> me when I tested it) and there is no report or debug
> window to tell what happened.
>
>
> Question for the experts: What should Form fromUser do
> when a user balks? Rectangle fromUser gives a zero
> area rectangle if the corner is higher left than the
> origin.
>
> Right now it returns a Form object with zero area.
> Most things that use form assume that this won't
> happen. I fixed BitmapFill cause I needed it for my
> other work but there are a lot of other places this
> comes up.
>
>
> Rather than return a zero area form, should Form
> fromUser:
>
>
> 1) signal an error?
> 2) return a default Form?
> 3) return the undefined object which will force the
> methods that use Form fromUser to deal with it
> promptly?
>
> Second point for Testers and Bug Squashers. There are
> probably many serious bugs in squeak that arise when a
> user input is used by a method that assumes the
> arguments its receiving are valid. Someone
> knowledgeable and clever should be able find methods
> that leap before they check.
>
> Can you write an inspector to check if a parameter is
> stored without being checked?
>
> Can you set a bunch of eyes to look for the cases
> where these things occur? Seems to me there must be a
> lot of cases and this would be a good thing to sic
> newbee apprentice bugsquashers on. A chance to do
> something useful while they learn the language and the
> code.
>
>
>  
> Yours in service,  Jerome Peace
>
>
> __________________________________
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> http://mail.yahoo.com'From Squeak3.7alpha of 11 September 2003 [latest 
> update: #5816] on 13 March 2004 at 6:20:31 pm'!
> "Change Set:		GrabFormFix
> Date:			13 March 2004
> Author:			wiz (Jerome Peace)
>
> Insure form is valid before using it.
>
> Form fromUser causes a lot of down the line problems.
>
> Most methods use the form supplied without checking to see if the user 
> might have balked. If the corner is above or left of the origin 
> fromUser returns an empty form with zero area.  Many down the line 
> users assume all the forms they are given are valid. And crash in some 
> horrible way if they aren't.
>
> Might be better for fromUser to return a undefined object and catch 
> the problem early?--wiz"!
>
>
> !BitmapFillStyle methodsFor: 'Morphic menu' stamp: 'wiz 3/13/2004 
> 18:08'!
> grabNewGraphicIn: aMorph event: evt
> 	"Used by any morph that can be represented by a graphic"
> 	| fill |
> 	fill  _ Form fromUser.
> 	fill height * fill width = 0 ifTrue: [^ self].
> 	self form: fill. "Insure form is valid before using it. --wiz"
> 	self direction: self form width @ 0.
> 	self normal: 0 @ self form height.
> 	aMorph changed.! !
>
--
Marcus Denker marcus at ira.uka.de