Pcell within library appears as "new independant topcell" in the Cells side bar in layout

edited February 2022 in General

Hello Matthias, all

i dunno how to put an explicit title on the behaviour i seen, nor found an answer to what i see in the forum, so sorry if this behaviour is intended and/or documented.
Actually, i make "huge" use of the library concept and of the Pcells. I recently upgraded from a rather old version (0.25..) and i have seen a behaviour appear in the cells side bar view. Let me explain:
Make a gds library called, say test.gds with a library title test_lib. Put in this library in a topcell (lets call it test) some standard patterns and somme Pcells (basic layout objects will do it, a circle for example) save this gds, close klayout and reopen it . make a new layout and then put an instance of the test libray in it. put other patterns (or not, doesn't matter)
you will have in the cells side bar view something like

Topcell
-> Test_lib.test
----> test_lib.Basic.CIRCLE(xxx)

which is what we can see in the old version.
then save and close this layout
If you simply reopen this layout, instead of having the view as above (which is what i expect and what i got with the "old" version, you will have

Topcell
-> Test_lib.test
---> test_lib.Basic.CIRCLE(xxx)
Basic.circle(xxx)

as you can notice the Pcell cell appear in the cell views as a "fake" or "ghost" independant topcell which can be for example , viewed, deleted, copied, etc

As soon as you try to put a new object instance (can be a pcell or a library pattern) these "independant topcell" disappear from the view.

if you delete them then reopen the saved file they do "magically" reappear...

So i dunno if is intended or not , or if there is a way to not have this feature but it make the cell tree view rather hard to "decode" and review...

any clue ?

Regards
Joël

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