Watch window freezes the system when Name contains non-ASCII symbols

[alexander-pastukhov]

Environment data

• PTVSD version: 15.8.18241.1
• OS and version: Windows 10 Enterprise LTSB 2016 - 64 bit
• Python version (& distribution if applicable, e.g. Anaconda): Python 2.7
• Using VS Code or Visual Studio: Visual Studio Community 2017 15.8.6 (VisualStudio.15.Release/15.8.6+28010.2041)

Actual behavior

When a non-ASCII symbol (e.g., Ä or Д) is entered in the Name in the Watch window during debugging, it crashes (see traceback below), freezing the system. I assume that this is Python 2 specific bug, as there are no problems with Python 3.6

Expected behavior

Should produce NameError, as in Python 3

Steps to reproduce:

1. Pause the execution with a breakpoint.
2. Enter Ä in the watch window.

Traceback

Traceback (most recent call last):
File "e:\software\microsoft visual studio\2017\community\common7\ide\extensions\microsoft\python\core\Packages\ptvsd\wrapper.py", line 1211, in done
fut.result()
File "e:\software\microsoft visual studio\2017\community\common7\ide\extensions\microsoft\python\core\Packages\ptvsd\futures.py", line 40, in result
reraise(self._exc_info)
File "e:\software\microsoft visual studio\2017\community\common7\ide\extensions\microsoft\python\core\Packages\ptvsd\futures.py", line 149, in callback
x = next(it)
File "e:\software\microsoft visual studio\2017\community\common7\ide\extensions\microsoft\python\core\Packages\ptvsd\wrapper.py", line 1760, in on_evaluate
msg = '\t'.join(str(s) for s in cmd_args)
File "e:\software\microsoft visual studio\2017\community\common7\ide\extensions\microsoft\python\core\Packages\ptvsd\wrapper.py", line 1760, in
msg = '\t'.join(str(s) for s in cmd_args)
UnicodeEncodeError: 'ascii' codec can't encode character u'\xc4' in position 0: ordinal not in range(128)