Duplicate closing node on node path operation

[Jabiertxof]

NEW BUG DESCRIPTION::
On a closed BSpline path, last node became duplicated when operating with other paths nodes. Attached example of the problem in SVG.

Steps to reproduce ONE:
1) open bspline.extranode.svg in current trunk
2) Select the big shape
--> tooltip show 38 nodes
3) Move it
--> Tooltip show 39 nodes

Steps to reproduce TWO:
1) open bspline.extranode.svg in current trunk
2) Move the node marked with the black circle
--> sometimes the node marked with the red circle changes
3) Unselect the path and select it again
--> the node marked with red circle is duplicated

~suv speculates it could be related to bugs:
Bug #515237: "Rotate shape adds node"
Bug #614628: ""Join selected nodes" adds an extraneous node when joining near-duplicate nodes"

=====
Inkscape version: 0.91+devel r14828, r14301

[su_v (suv-lp)]

Not reproduced with Inkscape 0.91 r13725 and 0.91+devel r14283 on OS X 10.7.5 (tested with default (new) prefs).

--
<off-topic>
Please don't forget to always include information about OS/platform and used Inkscape version / build revno to new bug reports, thank you.
</off-topic>

[Jabiertxof (jabiertxof)]

Thanks for your review and time, I also coulden't reproduce.

[su_v (suv-lp)]

JFTR - not reproduced on Ubuntu 14.04.2 LTS (VM 64bit, host: OS X 10.7.5) either, tested with Inkscape 0.91 r13725 and 0.91+devel r14283 (both from inkscape.dev PPAs).

[Jabiertxof (jabiertxof)]

Here are the bug example of the main bug

[su_v (suv-lp)]

Testing steps for new test case 'bspline.extranode.svg' with r14302 on OS X 10.7.5:
ONE (node count changes when moving a path): not reproduced
TWO (closing node duplicates after node-editing the path elsewhere): reproduced

[su_v (suv-lp)]

On 2015-08-14 20:13 (+0200), ~suv wrote:
> ONE (node count changes when moving a path): not reproduced

On the other hand, the node count displayed by the select tool does change to 39 if I rotate the path (similar to bug #515237), instead of moving it.

[su_v (suv-lp)]

Another observation with regard to node count displayed in the status bar by the select tool, before and after moving the path (r14302 on OS X 10.7.5):

If I lower the numeric precision to 7 and relaunch inkscape with the test case:
- initial node count: 37 nodes
- node count after first move: 38 nodes
- node count after third and later moves: 39

Reverting numeric precision again to default '8', relaunching inkscape: node count (38) again stays unchanged on move, and only changes on rotation (from 38 to 39).

[Discrete Games (discretegames)]

I can reproduce this bug in Windows 10, Inkscape 0.92.3 (2405546, 2018-03-11).

In fact it happens to me all the time when working with closed BSpline shapes. I made another bug report recently that I now realize is a duplicate of this one: https://bugs.launchpad.net/inkscape/+bug/1762093

If this is a precision issue would using much larger shapes fix (or at least avoid) it? I tried scaling up the shape in the provided svg and can no longer reproduce the bug. For now this appears to be a promising workaround!

[Diego R Guzman (yeco)]

This is still happening, and you can spent too much time fixing the duplicated nodes. Inkscape 0.92.4 (5da689c313, 2019-01-14)

[carlos santos (carlossantos1986)]

I can confirm this bug is still present in Inkscape 1.3 (0e150ed, 2023-07-21 , Linux appimage). I've seen it for several years but never bothers me much, but now I'm designing vectors for engraving with a cnc and this bug cause issues, most of the time, the "paranormal" added nodes are on top of each other, and that causes problems in the CAM software. I've seen it happen just by moving/rotating objects / boolean operations / applying path effects, you name it. For some reason it adds duplicated nodes of top of each other. I really like Inkscape but this bug alone cost me hours in the past months, in the mean time, I've switched to other software because I need to get work done, but I miss Inkscake... Sorry for the rant. Hope some king soul can find solve the issue. Tanks