RFR: 8189354: ArrayIndexOutOfBoundsException when listening to selection changes on TreeTableView [v8]

[Kevin Rushforth]

On Tue, 27 Apr 2021 19:18:59 GMT, mstr2 <github.com+43553916+mstr2 at openjdk.org> wrote:

>> This PR fixes the implementation of `ControlUtils.reducingChange`, which incorrectly computed adjacent removed indices, thus resulting in incorrect removal notifications.
>> 
>> Since there were no unit tests for this method, I also added a bunch of tests.
>> 
>> After applying this fix, I can no longer reproduce [JDK-8189354](https://bugs.openjdk.java.net/browse/JDK-8189354) and [JDK-8189228](https://bugs.openjdk.java.net/browse/JDK-8189228).
>
> mstr2 has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Use MockListObserver

I'm a bit confused about the various issues.

> The issues that are currently listed in the bug JDK-8189228 are not reproducible, so it can be closed as cannot reproduce

If any are reproducible before this fix, then closing as "cannot reproduce" is incorrect. Either close as a duplicate, or list that issue in this PR.

But... I thought based on the earlier discussion that one or more NPEs in TreeView multi-selection remain even after this which, which focuses on fixing IOOBE. Is this not the case?

-------------

PR: https://git.openjdk.java.net/jfx/pull/480