Re: [PATCH v3 1/3] Improve interaction between mouse-drag-region and scroll-margin

[Yuri D'Elia]

On Sat, Sep 25 2021, Yuri D'Elia wrote:
> Clicking inside the scroll-margin region still occasionally causes some
> regions to be selected, ....

I spent some extra time digging into this specific edge case that was
remaining, as I still consider it buggy.

To sum up: now the click and drag behave as expected within the
scroll-margin region, but I *still* noticed sometimes a word or a line
would unexpectedly be selected.

Turns out the code is correct. It's a much dumber problem:

When clicking inside the scroll-margin region, the point is moved and
the buffer is scrolled. So far so good.

So I would just click again on the same spot for testing. This would
scroll more. But it the mouse hasn't moved, so this event would *also*
count as a double-click (and triple, if done in succession) if done fast
enough.

It's technically correct, since you *might* be trying to do a legitimate
double-click. However, if you click within any autoscroll region, the
buffer is scrolled after releasing the button. Such attempt results in
two scrolls, or more. Having this select /anything/ and at the same time
move it away from view is broken IMHO.

My thinking would be that if scrolling happens between the down-mouse
and up-mouse event, we shouldn't count subsequent clicks as repeated.

However the repeat count seems to come from a higher level which I'm not
familiar with. I'm not sure how would I approach such a fix.

Ideas?