Node version:

(probably any)

ShellJS version (the most recent version/Github branch you see the bug on):

v0.7

Operating system:

(probably any)

Description of the bug:

cp('-n', 'foo', 'bar') fails if bar exists. This should succeed but do nothing.

Example ShellJS command to reproduce the error:

See above

This is related to shelljs/shx#67, as pointed out by @kirly-af