Morphic yellow cross of death

Well,

- your stack is truncated, is there more somewhere?
- can you say anything about how you got there?
- did you notice that lines was not nil by the time the stack was written:

        lines:     {a TextLine 1 to: 67 . a TextLine 68 to: 139 . a TextLine 140 to: 240 . ...etc...

Cheers,
Bob

On 9/16/13 5:26 PM, Nicolas Cellier wrote:

Lately I have many instances of these yellow cross over red background that happens when a low level morphic error is encountered.

It seems related to a MultiNewParagraph lines being nil like in following stack example.

I don't know if it can help a morphic guru, but I just hate those stateful behavior with volatile states...

Really hard to debug/understand!!!

Well, I can sort-of make it happen

- do you have the full SqueakDebug.log?
- did you copy the portion you sent from the file or did you do it another way? (like the mail bug report menu item)???
- you might think about upping the numbers in ContextPart>>errorReportOn: so we can see the full stack next time
[snip]
        strm position > (startPos+40000) ifTrue: [strm nextPutAll: '...etc...'.    "make 40000 much larger"
            ^ self].     "exit early"
        cnt > 60 ifTrue: [strm nextPutAll: '-- and more not shown --'.  ^ self].    "make 60 much larger"
[snip]

Cheers,
Bob

On 9/16/13 5:26 PM, Nicolas Cellier wrote:

Lately I have many instances of these yellow cross over red background that happens when a low level morphic error is encountered.

It seems related to a MultiNewParagraph lines being nil like in following stack example.

I don't know if it can help a morphic guru, but I just hate those stateful behavior with volatile states...

Really hard to debug/understand!!!

UndefinedObject(Object)>>error:
    Receiver: nil
    Arguments and temporary variables:
        aString:     'MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNone:'
    Receiver's instance variables:
nil

[] in WorldState>>displayWorldSafely:
    Receiver: a WorldState
    Arguments and temporary variables:
<<error during printing>
    Receiver's instance variables:
        hands:     {a HandMorph(3216)}
        activeHand:     a HandMorph(3216)
        viewBox:     0@0 corner: 1113@867
        canvas:     a FormCanvas on: DisplayScreen(1113x867x32)
        damageRecorder:     a DamageRecorder
        stepList:     a Heap(StepMessage(#stepAt: -> 3PButton(#toggleProjectLocalness 739))...etc...
        lastStepTime:     690046
        lastStepMessage:     nil
        lastCycleTime:     690046
        commandHistory:     a CommandHistory
        alarms:     a MorphicAlarmQueue()
        lastAlarmTime:     690046
        remoteServer:     nil
        multiCanvas:     nil

BlockClosure>>cull:cull:
    Receiver: [closure] in WorldState>>displayWorldSafely:
    Arguments and temporary variables:
        firstArg:     'MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNone:'
        secondArg:     nil
    Receiver's instance variables:
        outerContext:     WorldState>>displayWorldSafely:
        startpc:     97
        numArgs:     2

[] in BlockClosure>>ifError:
    Receiver: [closure] in WorldState>>displayWorldSafely:
    Arguments and temporary variables:
        errorHandlerBlock:     MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNon...etc...
        ex:     [closure] in WorldState>>displayWorldSafely:
    Receiver's instance variables:
        outerContext:     WorldState>>displayWorldSafely:
        startpc:     90
        numArgs:     0

BlockClosure>>cull:
    Receiver: [closure] in BlockClosure>>ifError:
    Arguments and temporary variables:
        firstArg:     MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNone:
    Receiver's instance variables:
        outerContext:     BlockClosure>>ifError:
        startpc:     40
        numArgs:     1

[] in MethodContext(ContextPart)>>handleSignal:
    Receiver: BlockClosure>>on:do:
    Arguments and temporary variables:
<<error during printing>
    Receiver's instance variables:
        sender:     BlockClosure>>ifError:
        pc:     17
        stackp:     3
        method:     (BlockClosure>>#on:do: "a CompiledMethod(680)")
        closureOrNil:     nil
        receiver:     [closure] in WorldState>>displayWorldSafely:

BlockClosure>>ensure:
    Receiver: [closure] in MethodContext(ContextPart)>>handleSignal:
    Arguments and temporary variables:
        aBlock:     [closure] in MethodContext(ContextPart)>>handleSignal:
        complete:     nil
        returnValue:     nil
    Receiver's instance variables:
        outerContext:     MethodContext(ContextPart)>>handleSignal:
        startpc:     98
        numArgs:     0

MethodContext(ContextPart)>>handleSignal:
    Receiver: BlockClosure>>on:do:
    Arguments and temporary variables:
        exception:     MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNone:
        val:     nil
    Receiver's instance variables:
        sender:     BlockClosure>>ifError:
        pc:     17
        stackp:     3
        method:     (BlockClosure>>#on:do: "a CompiledMethod(680)")
        closureOrNil:     nil
        receiver:     [closure] in WorldState>>displayWorldSafely:

MessageNotUnderstood(Exception)>>signal
    Receiver: MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNone:
    Arguments and temporary variables:

    Receiver's instance variables:
        messageText:     nil
        tag:     nil
        signalContext:     MessageNotUnderstood(Exception)>>signal
        handlerContext:     BlockClosure>>on:do:
        outerContext:     nil
        message:     findBinaryIndex: [closure] in MultiNewParagraph(NewParagraph)>>fastFin...etc...
        receiver:     nil
        reachedDefaultHandler:     false

UndefinedObject(Object)>>doesNotUnderstand: #findBinaryIndex:ifNone:
    Receiver: nil
    Arguments and temporary variables:
        aMessage:     findBinaryIndex: [closure] in MultiNewParagraph(NewParagraph)>>fastFi...etc...
        exception:     MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNone:
        resumeValue:     nil
    Receiver's instance variables:
nil

MultiNewParagraph(NewParagraph)>>fastFindFirstLineSuchThat:
    Receiver: a MultiNewParagraph
    Arguments and temporary variables:
        lineBlock:     [closure] in MultiNewParagraph(NewParagraph)>>lineIndexForPoint:
    Receiver's instance variables:
        text:     a Text for 'evaluate: textOrStream cue: aCue ifFail: failBlock logged: lo...etc...
        textStyle:     a TextStyle Bitmap DejaVu Sans 9
        firstCharacterIndex:     1
        container:     0@0 corner: 669@9999999
        lines:     {a TextLine 1 to: 67 . a TextLine 68 to: 139 . a TextLine 140 to: 240 . ...etc...
        positionWhenComposed:     0@0
        offsetToEnd:     1089
        maxRightX:     652
        selectionStart:     a CharacterBlock with index 278 and character Character tab and...etc...
        selectionStop:     a CharacterBlock with index 278 and character Character tab and ...etc...
        wantsColumnBreaks:     false
        focused:     true
        caretRect:     nil
        showCaret:     true
        presentationText:     nil
        presentationLines:     nil

MultiNewParagraph(NewParagraph)>>lineIndexForPoint:
    Receiver: a MultiNewParagraph
    Arguments and temporary variables:
        aPoint:     669@274
        i:     nil
        py:     274
    Receiver's instance variables:
        text:     a Text for 'evaluate: textOrStream cue: aCue ifFail: failBlock logged: lo...etc...
        textStyle:     a TextStyle Bitmap DejaVu Sans 9
        firstCharacterIndex:     1
        container:     0@0 corner: 669@9999999
        lines:     {a TextLine 1 to: 67 . a TextLine 68 to: 139 . a TextLine 140 to: 240 . ...etc...
        positionWhenComposed:     0@0
        offsetToEnd:     1089
        maxRightX:     652
        selectionStart:     a CharacterBlock with index 278 and character Character tab and...etc...
        selectionStop:     a CharacterBlock with index 278 and character Character tab and ...etc...
        wantsColumnBreaks:     false
        focused:     true
        caretRect:     nil
        showCaret:     true
        presentationText:     nil
        presentationLines:     nil

MultiNewParagraph>>displayOn:using:at:
    Receiver: a MultiNewParagraph
    Arguments and temporary variables:
        aCanvas:     a FormCanvas on: DisplayScreen(1113x867x32)
        displayScanner:     a MultiDisplayScanner
        somePosition:     80@436
        visibleRectangle:     0@0 corner: 669@274
        offset:     80@436
        leftInRun:     0
        line:     nil
        i:     nil
        iLimiT:     nil
    Receiver's instance variables:
        text:     a Text for 'evaluate: textOrStream cue: aCue ifFail: failBlock logged: lo...etc...
        textStyle:     a TextStyle Bitmap DejaVu Sans 9
        firstCharacterIndex:     1
        container:     0@0 corner: 669@9999999
        lines:     {a TextLine 1 to: 67 . a TextLine 68 to: 139 . a TextLine 140 to: 240 . ...etc...
        positionWhenComposed:     0@0
        offsetToEnd:     1089
        maxRightX:     652
        selectionStart:     a CharacterBlock with index 278 and character Character tab and...etc...
        selectionStop:     a CharacterBlock with index 278 and character Character tab and ...etc...
        wantsColumnBreaks:     false
        focused:     true
        caretRect:     nil
        showCaret:     true
        presentationText:     nil
        presentationLines:     nil

FormCanvas>>paragraph:bounds:color:
    Receiver: a FormCanvas on: DisplayScreen(1113x867x32)
    Arguments and temporary variables:
        para:     a MultiNewParagraph
        bounds:     0@0 corner: 669@450
        c:     Color black
        scanner:     a MultiDisplayScanner
    Receiver's instance variables:
        target:     nil
        filterSelector:     nil
        origin:     80@436
        clipRect:     77@436 corner: 752@710
        form:     DisplayScreen(1113x867x32)
        port:     a GrafPort
        shadowColor:     nil

TextMorphForEditView(TextMorph)>>drawOn:
    Receiver: a TextMorphForEditView(975)
    Arguments and temporary variables:
        aCanvas:     a FormCanvas on: DisplayScreen(1113x867x32)
        fauxBounds:     0@0 corner: 669@450
    Receiver's instance variables:
        bounds:     0@0 corner: 669@450
        owner:     a TransformMorph(1921)
        submorphs:     #()
        fullBounds:     0@0 corner: 669@450
        color:     Color black
        extension:     a MorphExtension (1256) [other:  (errorOnDraw -> true) (blinkStart -...etc...
        borderWidth:     0
        borderColor:     Color black
        textStyle:     a TextStyle Bitmap DejaVu Sans 9
        text:     a Text for 'evaluate: textOrStream cue: aCue ifFail: failBlock logged: lo...etc...
        wrapFlag:     true
        paragraph:     a MultiNewParagraph
        editor:     a SmalltalkEditor
        container:     nil
        predecessor:     nil
        successor:     nil
        backgroundColor:     nil
        margins:     nil
        editHistory:     nil
        editView:     a PluggableTextMorphPlus(3589)
        acceptOnCR:     false

FormCanvas(Canvas)>>draw:
    Receiver: a FormCanvas on: DisplayScreen(1113x867x32)
    Arguments and temporary variables:
        anObject:     a TextMorphForEditView(975)
    Receiver's instance variables:
        target:     nil
        filterSelector:     nil
        origin:     80@436
        clipRect:     77@436 corner: 752@710
        form:     DisplayScreen(1113x867x32)
        port:     a GrafPort
        shadowColor:     nil

FormCanvas(Canvas)>>drawMorph:
    Receiver: a FormCanvas on: DisplayScreen(1113x867x32)
    Arguments and temporary variables:
        aMorph:     a TextMorphForEditView(975)
    Receiver's instance variables:
        target:     nil
        filterSelector:     nil
        origin:     80@436
        clipRect:     77@436 corner: 752@710
        form:     DisplayScreen(1113x867x32)
        port:     a GrafPort
        shadowColor:     nil

[] in TextMorphForEditView(Morph)>>fullDrawOn:
    Receiver: a TextMorphForEditView(975)
    Arguments and temporary variables:
        aCanvas:     a FormCanvas on: DisplayScreen(1113x867x32)
    Receiver's instance variables:
        bounds:     0@0 corner: 669@450
        owner:     a TransformMorph(1921)
        submorphs:     #()
        fullBounds:     0@0 corner: 669@450
        color:     Color black
        extension:     a MorphExtension (1256) [other:  (errorOnDraw -> true) (blinkStart -...etc...
        borderWidth:     0
        borderColor:     Color black
        textStyle:     a TextStyle Bitmap DejaVu Sans 9
        text:     a Text for 'evaluate: textOrStream cue: aCue ifFail: failBlock logged: lo...etc...
        wrapFlag:     true
        paragraph:     a MultiNewParagraph
        editor:     a SmalltalkEditor
        container:     nil
        predecessor:     nil
        successor:     nil
        backgroundColor:     nil
        margins:     nil
        editHistory:     nil
        editView:     a PluggableTextMorphPlus(3589)
        acceptOnCR:     false

FormCanvas>>roundCornersOf:in:during:
    Receiver: a FormCanvas on: DisplayScreen(1113x867x32)
    Arguments and temporary variables:
        aMorph:     a TextMorphForEditView(975)
        bounds:     0@0 corner: 669@450
        aBlock:     [closure] in TextMorphForEditView(Morph)>>fullDrawOn:
    Receiver's instance variables:
        target:     nil
        filterSelector:     nil
        origin:     80@436
        clipRect:     77@436 corner: 752@710
        form:     DisplayScreen(1113x867x32)
        port:     a GrafPort
        shadowColor:     nil


--- The full stack ---
UndefinedObject(Object)>>error:
[] in WorldState>>displayWorldSafely:
BlockClosure>>cull:cull:
[] in BlockClosure>>ifError:
BlockClosure>>cull:
[] in MethodContext(ContextPart)>>handleSignal:
BlockClosure>>ensure:
MethodContext(ContextPart)>>handleSignal:
MessageNotUnderstood(Exception)>>signal
UndefinedObject(Object)>>doesNotUnderstand: #findBinaryIndex:ifNone:
MultiNewParagraph(NewParagraph)>>fastFindFirstLineSuchThat:
MultiNewParagraph(NewParagraph)>>lineIndexForPoint:
MultiNewParagraph>>displayOn:using:at:
FormCanvas>>paragraph:bounds:color:
TextMorphForEditView(TextMorph)>>drawOn:
FormCanvas(Canvas)>>draw:
FormCanvas(Canvas)>>drawMorph:
[] in TextMorphForEditView(Morph)>>fullDrawOn:
FormCanvas>>roundCornersOf:in:during:
 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
FormCanvas(Canvas)>>roundCornersOf:during:
TextMorphForEditView(Morph)>>fullDrawOn:
FormCanvas(Canvas)>>fullDraw:
FormCanvas(Canvas)>>fullDrawMorph:
[] in [] in TransformMorph>>drawSubmorphsOn:
Array(SequenceableCollection)>>reverseDo:
[] in TransformMorph>>drawSubmorphsOn:
FormCanvas>>transformBy:clippingTo:during:smoothing:
TransformMorph>>drawSubmorphsOn:
[] in TransformMorph(Morph)>>fullDrawOn:
FormCanvas>>roundCornersOf:in:during:
FormCanvas(Canvas)>

Ah another instance (see attachment)

This time I clicked in a debugger methodList and you can see that

(listSource itemSelectedAmongMultiple:  row) ifTrue: [

bugged because it did not answer a boolean...

2013/9/17 Bob Arning <[hidden email]>

Well, I can sort-of make it happen

- do you have the full SqueakDebug.log?
- did you copy the portion you sent from the file or did you do it another way? (like the mail bug report menu item)???
- you might think about upping the numbers in ContextPart>>errorReportOn: so we can see the full stack next time
[snip]
        strm position > (startPos+40000) ifTrue: [strm nextPutAll: '...etc...'.    "make 40000 much larger"
            ^ self].     "exit early"
        cnt > 60 ifTrue: [strm nextPutAll: '-- and more not shown --'.  ^ self].    "make 60 much larger"
[snip]

Cheers,
Bob

On 9/16/13 5:26 PM, Nicolas Cellier wrote:

Lately I have many instances of these yellow cross over red background that happens when a low level morphic error is encountered.

It seems related to a MultiNewParagraph lines being nil like in following stack example.

I don't know if it can help a morphic guru, but I just hate those stateful behavior with volatile states...

Really hard to debug/understand!!!

UndefinedObject(Object)>>error:
    Receiver: nil
    Arguments and temporary variables:
        aString:     'MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNone:'
    Receiver's instance variables:
nil

[] in WorldState>>displayWorldSafely:
    Receiver: a WorldState
    Arguments and temporary variables:
<<error during printing>
    Receiver's instance variables:
        hands:     {a HandMorph(3216)}
        activeHand:     a HandMorph(3216)
        viewBox:     0@0 corner: 1113@867
        canvas:     a FormCanvas on: DisplayScreen(1113x867x32)
        damageRecorder:     a DamageRecorder
        stepList:     a Heap(StepMessage(#stepAt: -> 3PButton(#toggleProjectLocalness 739))...etc...
        lastStepTime:     690046
        lastStepMessage:     nil
        lastCycleTime:     690046
        commandHistory:     a CommandHistory
        alarms:     a MorphicAlarmQueue()
        lastAlarmTime:     690046
        remoteServer:     nil
        multiCanvas:     nil

BlockClosure>>cull:cull:
    Receiver: [closure] in WorldState>>displayWorldSafely:
    Arguments and temporary variables:
        firstArg:     'MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNone:'
        secondArg:     nil
    Receiver's instance variables:
        outerContext:     WorldState>>displayWorldSafely:
        startpc:     97
        numArgs:     2

[] in BlockClosure>>ifError:
    Receiver: [closure] in WorldState>>displayWorldSafely:
    Arguments and temporary variables:
        errorHandlerBlock:     MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNon...etc...
        ex:     [closure] in WorldState>>displayWorldSafely:
    Receiver's instance variables:
        outerContext:     WorldState>>displayWorldSafely:
        startpc:     90
        numArgs:     0

BlockClosure>>cull:
    Receiver: [closure] in BlockClosure>>ifError:
    Arguments and temporary variables:
        firstArg:     MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNone:
    Receiver's instance variables:
        outerContext:     BlockClosure>>ifError:
        startpc:     40
        numArgs:     1

[] in MethodContext(ContextPart)>>handleSignal:
    Receiver: BlockClosure>>on:do:
    Arguments and temporary variables:
<<error during printing>
    Receiver's instance variables:
        sender:     BlockClosure>>ifError:
        pc:     17
        stackp:     3
        method:     (BlockClosure>>#on:do: "a CompiledMethod(680)")
        closureOrNil:     nil
        receiver:     [closure] in WorldState>>displayWorldSafely:

BlockClosure>>ensure:
    Receiver: [closure] in MethodContext(ContextPart)>>handleSignal:
    Arguments and temporary variables:
        aBlock:     [closure] in MethodContext(ContextPart)>>handleSignal:
        complete:     nil
        returnValue:     nil
    Receiver's instance variables:
        outerContext:     MethodContext(ContextPart)>>handleSignal:
        startpc:     98
        numArgs:     0

MethodContext(ContextPart)>>handleSignal:
    Receiver: BlockClosure>>on:do:
    Arguments and temporary variables:
        exception:     MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNone:
        val:     nil
    Receiver's instance variables:
        sender:     BlockClosure>>ifError:
        pc:     17
        stackp:     3
        method:     (BlockClosure>>#on:do: "a CompiledMethod(680)")
        closureOrNil:     nil
        receiver:     [closure] in WorldState>>displayWorldSafely:

MessageNotUnderstood(Exception)>>signal
    Receiver: MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNone:
    Arguments and temporary variables:

    Receiver's instance variables:
        messageText:     nil
        tag:     nil
        signalContext:     MessageNotUnderstood(Exception)>>signal
        handlerContext:     BlockClosure>>on:do:
        outerContext:     nil
        message:     findBinaryIndex: [closure] in MultiNewParagraph(NewParagraph)>>fastFin...etc...
        receiver:     nil
        reachedDefaultHandler:     false

UndefinedObject(Object)>>doesNotUnderstand: #findBinaryIndex:ifNone:
    Receiver: nil
    Arguments and temporary variables:
        aMessage:     findBinaryIndex: [closure] in MultiNewParagraph(NewParagraph)>>fastFi...etc...
        exception:     MessageNotUnderstood: UndefinedObject>>findBinaryIndex:ifNone:
        resumeValue:     nil
    Receiver's instance variables:
nil

MultiNewParagraph(NewParagraph)>>fastFindFirstLineSuchThat:
    Receiver: a MultiNewParagraph
    Arguments and temporary variables:
        lineBlock:     [closure] in MultiNewParagraph(NewParagraph)>>lineIndexForPoint:
    Receiver's instance variables:
        text:     a Text for 'evaluate: textOrStream cue: aCue ifFail: failBlock logged: lo...etc...
        textStyle:     a TextStyle Bitmap DejaVu Sans 9
        firstCharacterIndex:     1
        container:     0@0 corner: 669@9999999
        lines:     {a TextLine 1 to: 67 . a TextLine 68 to: 139 . a TextLine 140 to: 240 . ...etc...
        positionWhenComposed:     0@0
        offsetToEnd:     1089
        maxRightX:     652
        selectionStart:     a CharacterBlock with index 278 and character Character tab and...etc...
        selectionStop:     a CharacterBlock with index 278 and character Character tab and ...etc...
        wantsColumnBreaks:     false
        focused:     true
        caretRect:     nil
        showCaret:     true
        presentationText:     nil
        presentationLines:     nil

MultiNewParagraph(NewParagraph)>>lineIndexForPoint:
    Receiver: a MultiNewParagraph
    Arguments and temporary variables:
        aPoint:     669@274
        i:     nil
        py:     274
    Receiver's instance variables:
        text:     a Text for 'evaluate: textOrStream cue: aCue ifFail: failBlock logged: lo...etc...
        textStyle:     a TextStyle Bitmap DejaVu Sans 9
        firstCharacterIndex:     1
        container:     0@0 corner: 669@9999999
        lines:     {a TextLine 1 to: 67 . a TextLine 68 to: 139 . a TextLine 140 to: 240 . ...etc...
        positionWhenComposed:     0@0
        offsetToEnd:     1089
        maxRightX:     652
        selectionStart:     a CharacterBlock with index 278 and character Character tab and...etc...
        selectionStop:     a CharacterBlock with index 278 and character Character tab and ...etc...
        wantsColumnBreaks:     false
        focused:     true
        caretRect:     nil
        showCaret:     true
        presentationText:     nil
        presentationLines:     nil

MultiNewParagraph>>displayOn:using:at:
    Receiver: a MultiNewParagraph
    Arguments and temporary variables:
        aCanvas:     a FormCanvas on: DisplayScreen(1113x867x32)
        displayScanner:     a MultiDisplayScanner
        somePosition:     80@436
        visibleRectangle:     0@0 corner: 669@274
        offset:     80@436
        leftInRun:     0
        line:     nil
        i:     nil
        iLimiT:     nil
    Receiver's instance variables:
        text:     a Text for 'evaluate: textOrStream cue: aCue ifFail: failBlock logged: lo...etc...
        textStyle:     a TextStyle Bitmap DejaVu Sans 9
        firstCharacterIndex:     1
        container:     0@0 corner: 669@9999999
        lines:     {a TextLine 1 to: 67 . a TextLine 68 to: 139 . a TextLine 140 to: 240 . ...etc...
        positionWhenComposed:     0@0
        offsetToEnd:     1089
        maxRightX:     652
        selectionStart:     a CharacterBlock with index 278 and character Character tab and...etc...
        selectionStop:     a CharacterBlock with index 278 and character Character tab and ...etc...
        wantsColumnBreaks:     false
        focused:     true
        caretRect:     nil
        showCaret:     true
        presentationText:     nil
        presentationLines:     nil

FormCanvas>>paragraph:bounds:color:
    Receiver: a FormCanvas on: DisplayScreen(1113x867x32)
    Arguments and temporary variables:
        para:     a MultiNewParagraph
        bounds:     0@0 corner: 669@450
        c:     Color black
        scanner:     a MultiDisplayScanner
    Receiver's instance variables:
        target:     nil
        filterSelector:     nil
        origin:     80@436
        clipRect:     77@436 corner: 752@710
        form:     DisplayScreen(1113x867x32)
        port:     a GrafPort
        shadowColor:     nil

TextMorphForEditView(TextMorph)>>drawOn:
    Receiver: a TextMorphForEditView(975)
    Arguments and temporary variables:
        aCanvas:     a FormCanvas on: DisplayScreen(1113x867x32)
        fauxBounds:     0@0 corner: 669@450
    Receiver's instance variables:
        bounds:     0@0 corner: 669@450
        owner:     a TransformMorph(1921)
        submorphs:     #()
        fullBounds:     0@0 corner: 669@450
        color:     Color black
        extension:     a MorphExtension (1256) [other:  (errorOnDraw -> true) (blinkStart -...etc...
        borderWidth:     0
        borderColor:     Color black
        textStyle:     a TextStyle Bitmap DejaVu Sans 9
        text:     a Text for 'evaluate: textOrStream cue: aCue ifFail: failBlock logged: lo...etc...
        wrapFlag:     true
        paragraph:     a MultiNewParagraph
        editor:     a SmalltalkEditor
        container:     nil
        predecessor:     nil
        successor:     nil
        backgroundColor:     nil
        margins:     nil
        editHistory:     nil
        editView:     a PluggableTextMorphPlus(3589)
        acceptOnCR:     false

FormCanvas(Canvas)>>draw:
    Receiver: a FormCanvas on: DisplayScreen(1113x867x32)
    Arguments and temporary variables:
        anObject:     a TextMorphForEditView(975)
    Receiver's instance variables:
        target:     nil
        filterSelector:     nil
        origin:     80@436
        clipRect:     77@436 corner: 752@710
        form:     DisplayScreen(1113x867x32)
        port:     a GrafPort
        shadowColor:     nil

FormCanvas(Canvas)>>drawMorph:
    Receiver: a FormCanvas on: DisplayScreen(1113x867x32)
    Arguments and temporary variables:
        aMorph:     a TextMorphForEditView(975)
    Receiver's instance variables:
        target:     nil
        filterSelector:     nil
        origin:     80@436
        clipRect:     77@436 corner: 752@710
        form:     DisplayScreen(1113x867x32)
        port:     a GrafPort
        shadowColor:     nil

[] in TextMorphForEditView(Morph)>>fullDrawOn:
    Receiver: a TextMorphForEditView(975)
    Arguments and temporary variables:
        aCanvas:     a FormCanvas on: DisplayScreen(1113x867x32)
    Receiver's instance variables:
        bounds:     0@0 corner: 669@450
        owner:     a TransformMorph(1921)
        submorphs:     #()
        fullBounds:     0@0 corner: 669@450
        color:     Color black
        extension:     a MorphExtension (1256) [other:  (errorOnDraw -> true) (blinkStart -...etc...
        borderWidth:     0
        borderColor:     Color black
        textStyle:     a TextStyle Bitmap DejaVu Sans 9
        text:     a Text for 'evaluate: textOrStream cue: aCue ifFail: failBlock logged: lo...etc...
        wrapFlag:     true
        paragraph:     a MultiNewParagraph
        editor:     a SmalltalkEditor
        container:     nil
        predecessor:     nil
        successor:     nil
        backgroundColor:     nil
        margins:     nil
        editHistory:     nil
        editView:     a PluggableTextMorphPlus(3589)
        acceptOnCR:     false

FormCanvas>>roundCornersOf:in:during:
    Receiver: a FormCanvas on: DisplayScreen(1113x867x32)
    Arguments and temporary variables:
        aMorph:     a TextMorphForEditView(975)
        bounds:     0@0 corner: 669@450
        aBlock:     [closure] in TextMorphForEditView(Morph)>>fullDrawOn:
    Receiver's instance variables:
        target:     nil
        filterSelector:     nil
        origin:     80@436
        clipRect:     77@436 corner: 752@710
        form:     DisplayScreen(1113x867x32)
        port:     a GrafPort
        shadowColor:     nil


--- The full stack ---
UndefinedObject(Object)>>error:
[] in WorldState>>displayWorldSafely:
BlockClosure>>cull:cull:
[] in BlockClosure>>ifError:
BlockClosure>>cull:
[] in MethodContext(ContextPart)>>handleSignal:
BlockClosure>>ensure:
MethodContext(ContextPart)>>handleSignal:
MessageNotUnderstood(Exception)>>signal
UndefinedObject(Object)>>doesNotUnderstand: #findBinaryIndex:ifNone:
MultiNewParagraph(NewParagraph)>>fastFindFirstLineSuchThat:
MultiNewParagraph(NewParagraph)>>lineIndexForPoint:
MultiNewParagraph>>displayOn:using:at:
FormCanvas>>paragraph:bounds:color:
TextMorphForEditView(TextMorph)>>drawOn:
FormCanvas(Canvas)>>draw:
FormCanvas(Canvas)>>drawMorph:
[] in TextMorphForEditView(Morph)>>fullDrawOn:
FormCanvas>>roundCornersOf:in:during:
 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
FormCanvas(Canvas)>>roundCornersOf:during:
TextMorphForEditView(Morph)>>fullDrawOn:
FormCanvas(Canvas)>>fullDraw:
FormCanvas(Canvas)>>fullDrawMorph:
[] in [] in TransformMorph>>drawSubmorphsOn:
Array(SequenceableCollection)>>reverseDo:
[] in TransformMorph>>drawSubmorphsOn:
FormCanvas>>transformBy:clippingTo:during:smoothing:
TransformMorph>>drawSubmorphsOn:
[] in TransformMorph(Morph)>>fullDrawOn:
FormCanvas>>roundCornersOf:in:during:
FormCanvas(Canvas)>

To get better info next time

- you might think about upping the numbers in ContextPart>>errorReportOn: so we can see the full stack next time
[snip]
        strm position > (startPos+40000) ifTrue: [strm nextPutAll: '...etc...'.    "make 40000 much larger"
            ^ self].     "exit early"
        cnt > 60 ifTrue: [strm nextPutAll: '-- and more not shown --'.  ^ self].    "make 60 much larger"
[snip]

I'll be looking at what you have sent.

Also, do you have a Transcript open when this happens? Is anything written to it around the time of the error (the previous error, perhaps, more than this latest one)?

Cheers,
Bob

On 9/17/13 4:26 PM, Nicolas Cellier wrote:

- you might think about upping the numbers in ContextPart>>errorReportOn: so we can see the full stack next time
[snip]
        strm position > (startPos+40000) ifTrue: [strm nextPutAll: '...etc...'.    "make 40000 much larger"
            ^ self].     "exit early"
        cnt > 60 ifTrue: [strm nextPutAll: '-- and more not shown --'.  ^ self].    "make 60 much larger"
[snip]

What sort of select/deselect/removes had you done to this ChangeList?

Cheer,
Bob

On 9/17/13 4:26 PM, Nicolas Cellier wrote:

Ah, sorry, it was not a debugger, it was a ChangeList, and curiously, the listSelections effectively contains a non boolean (nil)
 #(false false false true true nil true false false false false false false false false false false)

Well, this I can reproduce.

So if we look at this puppy:
========================================
!PluggableListMorphOfMany methodsFor: 'event handling' stamp: 'raa 9/17/2013 18:02'!
mouseMove: event
    "The mouse has moved, as characterized by the event provided.  Adjust the scrollbar, and alter the selection as appropriate"

    | oldIndex oldVal row index bobsDebugging |
   
    bobsDebugging _ OrderedCollection new.
    bobsDebugging add: {'1'. dragOnOrOff}.
    event position y < self top
        ifTrue:
            [scrollBar scrollUp: 1.
            row := self rowAtLocation: scroller topLeft + (1 @ 1)]
        ifFalse:
            [row := event position y > self bottom
                ifTrue:
                    [scrollBar scrollDown: 1.
                    self rowAtLocation: scroller bottomLeft + (1 @ -1)]
                ifFalse: [ self rowAtLocation: event position]].
    row = 0 ifTrue: [^super mouseDown: event].
    index := self modelIndexFor: row.

    model okToChange ifFalse: [^self].    "No change if model is locked"
    bobsDebugging add: {'2'. dragOnOrOff}.

    dragOnOrOff ifNil:
            ["Was not set at mouse down, which means the mouse must have gone down in an area where there was no list item"
            dragOnOrOff := (self listSelectionAt: index) not].
    bobsDebugging add: {'3'. dragOnOrOff}.

    "Set meaning for subsequent dragging of selection"
    oldIndex := self getCurrentSelectionIndex.
    oldIndex ~= 0 ifTrue: [oldVal := self listSelectionAt: oldIndex].

    "Set or clear new primary selection (listIndex)"
    dragOnOrOff
        ifTrue: [self changeModelSelection: index]
        ifFalse: [self changeModelSelection: 0].

    "Need to restore the old one, due to how model works, and set new one."
    oldIndex ~= 0 ifTrue: [self listSelectionAt: oldIndex put: oldVal].
    bobsDebugging add: {'4'. dragOnOrOff}.
    self listSelectionAt: index put: dragOnOrOff.
! !
==========================================
I added some debugging code which reports

an OrderedCollection(#('1' false) #('2' false) #('3' false) #('4' nil))

So we clobbered dragOnOrOff between the 3rd and 4th entries in the list. That's happening because of:

============================================
!PluggableListMorph methodsFor: 'model access' stamp: 'kb 6/5/2013 21:12'!
changeModelSelection: anInteger
    " Change the model's selected item index to be anInteger. Enable the pre selection highlight. Step the World forward to let the pre selection highlight take effect. "

    self rowAboutToBecomeSelected: (self uiIndexFor: anInteger).
    World doOneCycle.
    setIndexSelector ifNotNil: [
        model perform: setIndexSelector with: anInteger ].! !
=============================================

The World doOneCycle permits another ui event to be processed while we are still in the mouseMove:. If the event is a mouseUp: then

mouseUp: event

    dragOnOrOff := nil.  "So improperly started drags will have not effect"

kaboom.

Cheers,
Bob

On 9/17/13 4:26 PM, Nicolas Cellier wrote:

Ah, sorry, it was not a debugger, it was a ChangeList, and curiously, the listSelections effectively contains a non boolean (nil)
 #(false false false true true nil true false false false false false false false false false false)

So, the question is do they really need #doOneCycle or something less, like #displayWorldSafely

Cheers,
Bob

On 9/17/13 6:36 PM, Nicolas Cellier wrote:

Ah we cross posted, good find!

Those guys messing with World doOneCycle are just like the sorcerer's apprentice...