Create fallback with old arg_split, incase CommandLineToArgvW is missing.

IPython/utils/_process_win32.py

@@ -151,26 +151,51 b' def getoutput(cmd):'
         out = ''
     return out
 
-
-CommandLineToArgvW = ctypes.windll.shell32.CommandLineToArgvW
-CommandLineToArgvW.arg_types = [LPCWSTR, POINTER(c_int)]
-CommandLineToArgvW.res_types = [POINTER(LPCWSTR)]
-LocalFree = ctypes.windll.kernel32.LocalFree
-LocalFree.res_type = HLOCAL
-LocalFree.arg_types = [HLOCAL]
-
-def arg_split(commandline, posix=False):
-    """Split a command line's arguments in a shell-like manner.
-
-    This is a special version for windows that use a ctypes call to CommandLineToArgvW
-    to do the argv splitting. The posix paramter is ignored.
-    """
-    #CommandLineToArgvW returns path to executable if called with empty string.
-    if commandline.strip() == "":
-        return []
-    argvn = c_int()
-    result_pointer = CommandLineToArgvW(py3compat.cast_unicode(commandline.lstrip()), ctypes.byref(argvn))
-    result_array_type = LPCWSTR * argvn.value
-    result = [arg for arg in result_array_type.from_address(result_pointer)]
-    retval = LocalFree(result_pointer)
-    return result
+try:
+    CommandLineToArgvW = ctypes.windll.shell32.CommandLineToArgvW
+    CommandLineToArgvW.arg_types = [LPCWSTR, POINTER(c_int)]
+    CommandLineToArgvW.res_types = [POINTER(LPCWSTR)]
+    LocalFree = ctypes.windll.kernel32.LocalFree
+    LocalFree.res_type = HLOCAL
+    LocalFree.arg_types = [HLOCAL]
+    
+    def arg_split(commandline, posix=False):
+        """Split a command line's arguments in a shell-like manner.
+
+        This is a special version for windows that use a ctypes call to CommandLineToArgvW
+        to do the argv splitting. The posix paramter is ignored.
+        """
+        #CommandLineToArgvW returns path to executable if called with empty string.
+        if commandline.strip() == "":
+            return []
+        argvn = c_int()
+        result_pointer = CommandLineToArgvW(py3compat.cast_unicode(commandline.lstrip()), ctypes.byref(argvn))
+        result_array_type = LPCWSTR * argvn.value
+        result = [arg for arg in result_array_type.from_address(result_pointer)]
+        retval = LocalFree(result_pointer)
+        return result
+except AttributeError:
+    import shlex
+    #alternative if CommandLineToArgvW is not available
+    def arg_split(s, posix=False):
+        """Split a command line's arguments in a shell-like manner.
+
+        This is a modified version of the standard library's shlex.split()
+        function, but with a default of posix=False for splitting, so that quotes
+        in inputs are respected."""
+
+        # Unfortunately, python's shlex module is buggy with unicode input:
+        # http://bugs.python.org/issue1170
+        # At least encoding the input when it's unicode seems to help, but there
+        # may be more problems lurking.  Apparently this is fixed in python3.
+        is_unicode = False
+        if (not py3compat.PY3) and isinstance(s, unicode):
+            is_unicode = True
+            s = s.encode('utf-8')
+        lex = shlex.shlex(s, posix=posix)
+        lex.whitespace_split = True
+        tokens = list(lex)
+        if is_unicode:
+            # Convert the tokens back to unicode.
+            tokens = [x.decode('utf-8') for x in tokens]
+        return tokens