QAbstractItemModel Subclass duplicate entries

[caduel]

You have to remember the last parent chain.
If the next directory chain (your list in line 31) shares a common prefix with the last line you parsed, then remove only all those parents that do not match.

Example:

path           list        parents
/a/b/c/d  -> [a,b,c,d]   [p1, p2, p3, p4]
/a/b/e    -> [a,b,e]

path           list        parents
/a/b/c/d  -> [a,b,c,d]   [p1, p2, p3, p4]
/a/b/e    -> [a,b,e]

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Then you reduce parents to [p1, p2] and insert your new item under that chain.
You must not create a new parent chain all over for each line you parse.


Note: this algorithm assumes that the lines are sorted properly, which they should be in your case.

HTH

PS: I did not quite see where you "clear" your parent list.
Line 35 is beyond my understanding, too. Looks strange to me.
(I did not study your code in detail, sorry.)