"AttributeError: 'x' object has no attribute 'y'" for original Oblivion files

[Allofich]

Issue Overview

Some .nif files that come with Oblivion have an "AttributeError: 'NoneType' object has no attribute 'data'" error on import.

Version Information

Blender Niftools Addon Version Info

Built the addon using the following: Python 3.11 New Pyffi: https://github.com/Candoran2/new-pyffi/commit/6d113fdcfcf950eae138f7e75efcc6b057c1d605 New nif xml: https://github.com/Candoran2/nifxml/commit/d0ab9271e2c2bf75eacb46082b93e1d304b551e6 Latest blender addon code at: https://github.com/Candoran2/blender_nif_plugin/commit/cc4012830897ed32c378c3a2e5335e68d7ef3d48

Blender Version Info

3.4

Platform information

Windows 11 22H2

Steps to Reproduce

[Ordered list of the steps required for recreating the issue, including settings]

1. Build the latest blender_niftools_addon using the code versions listed above.
2. Import the problem mesh from Oblivion (below) into Blender.
3. The file is imported but has an error.

Expected Result

Should import without errors.

Actual Result

Imports with an error.

Console Output

niftools:INFO:Inserting key 'CLaw_L01'
Traceback (most recent call last):
  File "****\AppData\Roaming\Blender Foundation\Blender\3.4\scripts\addons\io_scene_niftools\operators\nif_import_op.py", line 134, in execute
    return NifImport(self, context).execute()
  File "****\AppData\Roaming\Blender Foundation\Blender\3.4\scripts\addons\io_scene_niftools\nif_import.py", line 131, in execute
    self.import_root(root)
  File "****\AppData\Roaming\Blender Foundation\Blender\3.4\scripts\addons\io_scene_niftools\nif_import.py", line 159, in import_root
    b_obj = self.import_branch(root_block)
  File "****\AppData\Roaming\Blender Foundation\Blender\3.4\scripts\addons\io_scene_niftools\nif_import.py", line 234, in import_branch
    b_child = self.import_branch(n_child, b_armature=b_armature)
  File "****\AppData\Roaming\Blender Foundation\Blender\3.4\scripts\addons\io_scene_niftools\nif_import.py", line 200, in import_branch
    return self.objecthelper.import_geometry_object(b_armature, n_block)
  File "****\AppData\Roaming\Blender Foundation\Blender\3.4\scripts\addons\io_scene_niftools\modules\nif_import\object\__init__.py", line 135, in import_geometry_object
    self.mesh.import_mesh(n_block, b_obj)
  File "****\AppData\Roaming\Blender Foundation\Blender\3.4\scripts\addons\io_scene_niftools\modules\nif_import\geometry\mesh\__init__.py", line 167, in import_mesh
    self.morph_anim.import_morph_controller(n_block, b_obj)
  File "****\AppData\Roaming\Blender Foundation\Blender\3.4\scripts\addons\io_scene_niftools\modules\nif_import\animation\morph.py", line 98, in import_morph_controller
    morph = n_morph_ctrl.interpolators[morph_i].data.data
AttributeError: 'NoneType' object has no attribute 'data'

Nif File

claw_l.zip