Environment data

VS Code version: 1.19.1
Python Extension version: 0.9.1
Python Version: 3.6.3
OS and version: Ubuntu 14.04

Actual behavior

Suppose you have a function with signature foo(bar=None). If you type foo(ba it displays suggestions to complete the argument. If you hit Enter to accept the suggestion it enters bar=None.

Expected behavior

The completion should just be bar= without the default value None. After all, if we wanted the default value we wouldn't be typing bar. We're trying to change bar to something other than its default.

As it is you have to backspace over the default value to replace it.

I flip back and forth between VSCode and Jupyter notebooks a lot. Notebooks just complete with bar= and it is really convenient.

Steps to reproduce:

As above.