Mirror LPE problem when modifying curve points location

This is the additional discovery file. As you can see, Rotate Copies has a unexpected behavior.

crash confirmed using file "Bug Testing" from comment 1.
I get a number of DOS warning messages saying:

** (inkscape.exe:10748): WARNING **: encountered non finite point when evaluating snapping callback

then get a standard crash with the creation of a backup file.
the unexpected behavior when editing a node is probably related to the fact that this object is using the spiro mode of rendering

A strange behavior is observed within b-splines, but no crash there. Nodes are deleted as I moved node using b-spline and the shape of the object is dramatically changed.

For B-Spline, you can just make a B-Spline object, and then mirror it, and then attempt to move nodes, and behold strange behavior.

For the above, I observed it with pre3 and pre4 version of Inkscape under Windows 10.

@Reptorian: I think I fix the bug but coulden't see the problem with BSPline. could you attach a file with the bug?
Thanks

Any body can confirm this bug is full fixed in r.15356 of trunk to backport to 0.92.x?

@Jabertxof - I can reproduce the issue with BSpline using Inkscape 0.92pre4 r15267 and lp:inkscape/0.92.x r15283 (on OS X 10.7.5):

1) launch inkscape (new doc, default prefs)
2) draw a bspline shape (open)
3) add mirror symmetry LPE
4) change Mode to 'X from middle knot'
5) switch to node tool
6) select, grab and drag one of the end nodes of the original bspline paths
--> inkscape pauses, keeps pointer grabbed and ultimately displaces the grabbed node unexpectedly.

Will test with latest trunk on Ubuntu 14.04 next.

su_v wrote:
> Will test with latest trunk on Ubuntu 14.04 next.

On Ubuntu 14.04.5 LTS:
- reproduced with lp:inkscape r15353 (from PPA)
- not reproduced with lp:inkscape r15366 (local build)
based on the steps provided in comment #8.

Thanks very much for confirm the fix su_v!

Backported fix of trunk r.r15366 to 0.92.x r.15284