As usually happens. While I'm writing my "please help" post I end up figuring out the problem on my own. Still, I will put my findings here to hopefully help someone else.
A few months ago I hacked together a script to randomly distort path points. It's not a perfect script but it worked fine for my use and saved me a ton of time.
Now after upgrading to 2018 it just beachballs the mac and gets stuck in an endless loop. When I detect a compound path I do this:
newItem = newCompoundPath.pathItems.add();
dupeAndWarp(comp, newItem, hVar, vVar);
comp is an pathitem of the compound path, which becomes "source" inside the dupeAndWarp method. Then inside dupeAndWarp, I transfer properties of the source item to the newpath (created by the caller), and then fill it with points using this loop:
function dupeAndWarp(source, newpath, hVar, vVar) {
.....
for (i=0; i<source.pathPoints.length; i++) {
var newPoint = idoc.pathItems[0].pathPoints.add();
var anchor = source.pathPoints.anchor;
var left = source.pathPoints.leftDirection;
var right = source.pathPoints.rightDirection;
var moveX = (Math.random() * hVar * 2) - hVar;
var moveY = (Math.random() * vVar * 2) - vVar;
newPoint.anchor = Array(anchor[0] + moveX, anchor[1] + moveY);
newPoint.leftDirection = Array(left[0] + moveX, left[1] + moveY);
newPoint.rightDirection = Array(right[0] + moveX, right[1] + moveY);
newPoint.pointType = source.pathPoints.pointType;
}
Which is where it's getting stuck. In CC 2017 this worked fine. What I discovered is that in 2018 the source.pathPoints.lenth is growing by one each time I do:
var newPoint = idoc.pathItems[0].pathPoints.add();
In the past this created a new point to the newCompoundPath that I added. But I suppose using pathItem[0] is sloppy and assumes that the item in [0] is the newest one that was added. The reason I did this was that the demo I found did it. I replaced that with "newpath and it works fine now.
Conclusion.. in 2018 we can no longer assume what pathItem[0] is going to be.
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