Raycaster bug : wrong face index

[ArpegorPSGH]

In one of my node trees when veryfying proper working, I found out that when hitting the first polygon of the mesh, -1 gets returned instead of 0, while everything else is normal. Attached is a MWE.
Bug raycaster_2022_04_28_17_11.zip

[zeffii]

interestingly - in this scenario

        if I.is_linked:
            I.sv_set([[r[2] if r[2] else -1 for r in L] for L in RL])

r[2] must be evaluating to False. RL is [[(Vector((0.0, 0.0, -1.0)), Vector((0.0, 0.0, 1.0)), 0, 1.0)]]

from mathutils import Vector

RL = [[(Vector((0.0, 0.0, -1.0)), Vector((0.0, 0.0, 1.0)), 0, 1.0)]]
F = [[r[2] if r[2] else -1 for r in L] for L in RL]
print(F)
>>> [[-1]]

https://docs.blender.org/api/current/mathutils.bvhtree.html?highlight=mathutils%20bvhtree#mathutils.bvhtree.BVHTree.ray_cast
ray_cast returns tuple( Vector location, Vector normal, int index, float distance )
and the first polygon's index being 0, results in r[2] evaluating to False. and therefore is replaced by -1 .

we will have to check against None explicitly.

[zeffii]

nice catch @ArpegorPSGH

[Durman]

If we stick to pep8 - https://pep8.org/#programming-recommendations
It should be something is not None

[zeffii]

even better