`vtkmodules/__init__.py` Yields Infinite Loop
The while loop in vtkmodules/__init__.py
yields an infinite loop on Windows because the dirname
of C:\
on Windows is always C:\
. This never becomes "", ".", or "/". That would only work on a Linux system.
r"""
Currently, this package is experimental and may change in the future.
"""
from __future__ import absolute_import
import sys
def _windows_dll_path():
import os
_vtk_python_path = r"C:\VTK\bin\Lib\site-packages\vtkmodules"
_vtk_dll_path = r"C:\VTK\bin"
# Compute the DLL path based on the location of the file and traversing up
# the installation prefix to append the DLL path.
_vtk_dll_directory = os.path.dirname(os.path.abspath(__file__))
# Loop while we have components to remove.
print("Folder Search:")
print("==============")
while _vtk_python_path not in ("", ".", "/"):
# Strip a directory away.
_vtk_python_path = os.path.dirname(_vtk_python_path)
_vtk_dll_directory = os.path.dirname(_vtk_dll_directory)
if _vtk_python_path != "C:\\":
print(_vtk_python_path)
print("==============")
print()
_vtk_dll_directory = os.path.join(_vtk_dll_directory, _vtk_dll_path)
print(f"VTK DLL Directory: {_vtk_dll_directory}")
print()
print("Adding DLLs...")
if os.path.exists(_vtk_dll_directory):
# We never remove this path; it is required for VTK to work and there's
# no scope where we can easily remove the directory again.
print(f"DLL: {_vtk_dll_directory}")
_ = os.add_dll_directory(_vtk_dll_directory)
print()
print("Build tree...")
# Build tree support.
try:
from . import _build_paths
# Add any paths needed for the build tree.
for path in _build_paths.paths:
if os.path.exists(path):
print(f"Path: {path}")
_ = os.add_dll_directory(path)
except ImportError:
# Relocatable install tree (or non-Windows).
print("Passing: Relocatable install tree")
pass
print()
print("Imported!")
# CPython 3.8 added behaviors which modified the DLL search path on Windows to
# only search "blessed" paths. When importing SMTK, ensure that SMTK's DLLs are
# in this set of "blessed" paths.
if sys.version_info >= (3, 8) and sys.platform == "win32":
_windows_dll_path()
# ------------------------------------------------------------------------------
# this little trick is for static builds of VTK. In such builds, if
# the user imports this Python package in a non-statically linked Python
# interpreter i.e. not of the of the VTK-python executables, then we import the
# static components importer module.
try:
from . import vtkCommonCore
except ImportError:
import _vtkmodules_static
# ------------------------------------------------------------------------------
# get the version
__version__ = "9.0.3"
The above leads to an infinite loop in the while
loop because the dirname
of C:\
in Windows is always C:\
:
❯ py
Python 3.8.10 (tags/v3.8.10:3d8993a, May 3 2021, 11:48:03) [MSC v.1928 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> print(os.path.dirname("C:\\"))
C:\
>>>
Running the above __init__.py
code yields:
❯ py
Python 3.8.10 (tags/v3.8.10:3d8993a, May 3 2021, 11:48:03) [MSC v.1928 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import vtk
Folder Search:
==============
C:\VTK\bin\Lib\site-packages
C:\VTK\bin\Lib
C:\VTK\bin
C:\VTK
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "C:\Program Files\Python38\lib\site-packages\vtk.py", line 30, in <module>
all_m = importlib.import_module('vtkmodules.all')
File "C:\Program Files\Python38\lib\importlib\__init__.py", line 127, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "C:\Program Files\Python38\lib\site-packages\vtkmodules\__init__.py", line 61, in <module>
_windows_dll_path()
File "C:\Program Files\Python38\lib\site-packages\vtkmodules\__init__.py", line 23, in _windows_dll_path
_vtk_dll_directory = os.path.dirname(_vtk_dll_directory)
File "C:\Program Files\Python38\lib\ntpath.py", line 223, in dirname
return split(p)[0]
File "C:\Program Files\Python38\lib\ntpath.py", line 187, in split
d, p = splitdrive(p)
KeyboardInterrupt
>>>
The fix to this is to add "C:\\"
and "C:/"
to the tuple in the while loop:
while _vtk_python_path not in ("", ".", "/", "C:\\", "C:/"):
Edited by Adam Hendry