there are still undo-bugs:

have two tabs, type something (multiple lines) in the first (main) tab,
switch to the second, type something,
switch back to first tab and start undoing.
the first line gets undone ok, then it starts duplication the code ...
i had a case where i couldn't select or edit the top of the code anymore.

save and reopen rescued the project ..

F

from the case where i could only recover by save-reopen:
( not sure when the out of memory error occured, but there should have been enough mem available anyway ..? )
Code:

java.lang.OutOfMemoryError
javax.swing.text.BadLocationException: Length must be positive
	at javax.swing.text.AbstractDocument.getText(AbstractDocument.java:810)
	at processing.app.syntax.JEditTextArea.getText(JEditTextArea.java:916)
	at processing.app.syntax.JEditTextArea.getLineText(JEditTextArea.java:944)
	at processing.app.syntax.JEditTextArea.xToOffset(JEditTextArea.java:621)
	at processing.app.syntax.InputHandler$prev_line.actionPerformed(InputHandler.java:940)
	at processing.app.syntax.InputHandler.executeAction(InputHandler.java:286)
	at processing.app.syntax.DefaultInputHandler.keyPressed(DefaultInputHandler.java:210)
	at processing.app.syntax.JEditTextArea.processKeyEvent(JEditTextArea.java:1630)
	at java.awt.Component.processEvent(Component.java:4975)
	at java.awt.Container.processEvent(Container.java:1613)
	at java.awt.Component.dispatchEventImpl(Component.java:3681)
	at java.awt.Container.dispatchEventImpl(Container.java:1671)
	at java.awt.Component.dispatchEvent(Component.java:3543)
	at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1713)
	at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:627)
	at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:831)
	at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:741)
	at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:592)
	at java.awt.Component.dispatchEventImpl(Component.java:3572)
	at java.awt.Container.dispatchEventImpl(Container.java:1671)
	at java.awt.Window.dispatchEventImpl(Window.java:1606)
	at java.awt.Component.dispatchEvent(Component.java:3543)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:456)
	at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:234)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:184)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:178)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:170)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:100)
 

ok, here's some code to reproduce (parts) of the bug:

Code:

{TAB 1}
int[] ints;

void setup()
{
    size( 100,100);
    ints = new int[10];
}

void draw()
{
    for (int i=0; i<100; i++)
    {
	  ints[i]++;  // raise exception here
    }
}
 

Code:

{TAB 2}
/*
a
b
c
d
e
f
g
h
i
j
k
l
m
n
o
p
q
r
s
t
u
v
w
x
y
z
*/
 

to reproduce the bug:
- cut (command-x) half the comment from tab 2
- run the sketch, raises exception
- go to tab 2
- undo the cutting

this will not only raise the exception mentioned earlier it as well will give you the strange insertion bug (lost linendings, code duplication).

( i'm not able to reproduce the scroll misbehaviour .. but i think it's tied to the unpredictable length of the via undo wrongly re-inserted code )

F