Fix env passed to command, drop docfx.cmd detection

autoapi/mappers/dotnet.py

@@ -1,6 +1,5 @@
 import re
 import os
-import platform
 import subprocess
 import traceback
 import shutil
@@ -14,10 +13,6 @@ from sphinx.errors import ExtensionError
 from .base import PythonMapperBase, SphinxMapperBase
 
 
-DOCFX_COMMAND = 'docfx'
-if platform.system() == 'Windows':
-    DOCFX_COMMAND = 'docfx.cmd'
-
 # Doc comment patterns
 DOC_COMMENT_PATTERN = r'''
     \<%(tag)s
@@ -73,14 +68,16 @@ class DotNetSphinxMapper(SphinxMapperBase):
             all_files.add(_file)
         if all_files:
             try:
-                command = [DOCFX_COMMAND, 'metadata', '--raw', '--force']
+                command = ['docfx', 'metadata', '--raw', '--force']
                 command.extend(all_files)
                 proc = subprocess.Popen(
                     ' '.join(command),
                     stdout=subprocess.PIPE,
                     stderr=subprocess.PIPE,
+                    shell=True,
                     env=dict((key, os.environ[key])
-                             for key in ['PATH', 'HOME']
+                             for key in ['PATH', 'HOME', 'SYSTEMROOT',
+                                         'USERPROFILE', 'WINDIR']
                              if key in os.environ),
                 )
                 _, error_output = proc.communicate()