See :help local-options for more details, but essentially, we have to be
very careful with how we set window-local options on popup windows,
because buffers might take some window-local options from the last
window they were displayed in with them to the new window in certain
circumstances.
This commit changes the backup/restore for the window options so that
the possible window-local options that might get clobbered are saved
from the original active window and reapplied to the preview window just
before it's closed. This ensures any buffers loaded from the picker will
have the same window options applied that were in the active window when
fzf was opened.
Whenever the file ends with newline, the builtin previewer was adding an
empty line at the end of the file. That's a side effect splitting and
rejoining the lines with \n. Basically, when we split a\nb\nc\n we get
{'a', 'b', 'c', ''}, then nvim_buf_set_lines treats each item in the
table as a line, and inserts an empty line at the end.
We do need to account for files that don't end with a new line though,
hence the check.
I don't have a way to test the \r\n logic locally, no Windows hosts
around, but it should work too.
bhagwan
John Drouhard
francisco souza