Panic in alternate screen when passing empty word list

[SimonRenblad]

Passing an empty word list, either directly or piped through stdin, fails at:

thread 'main' panicked at src/ui.rs:97:35: index out of bounds: the len is 0 but the index is 0

Which would be fine, except for it remaining on the alternate screen, so I need to tput rmcup to get out.

I understand that this is not a typical problem when reading directly from a file, but I tend to pipe inputs into ttyper and whenever a previous command in the pipeline fails I get this error.

I would propose to check the length of contents before enabling raw mode in main.