• VSCode Version: 1.26.0
• OS Version: macOS

Steps to Reproduce:

1. run code '' in command line.
2. VS Code seems opened a workspace of current directory folder, like code .

Does this issue occur when all extensions are disabled?: Yes

Reason the above behavior is improper

When I run some command like code "$(some command to get the file)" (e.g. code "$(which "$1")" in Linux), if the inner command failed, it return empty string as argument. VSCode shouldn't open current directory and replace the workspace (which is annoying), but should just open or focus the application instead.