Neovim assign shortcut for compiling and running a scala file

Question

Currently, after writing a scala program I have to invoke the three commands:

1. File save
2. compile the file
3. run the program

How to assign a shortcut for steps 2 and 3 above?

Answer 1

If your command to compile is: :scalac -classpath . % and your command to run is :terminal scala -classpath . %:r to associate them to the shortcuts F7 and Ctrl-F5 respectively you could add the following lines in your init.vim file:

nnoremap <F7> :scalac -classpath . %<CR>
nnoremap <C-F5> :terminal scala -classpath . %:r<CR>

You could also configure Vim to associate :make to scalac that allow you to get the compiler error in the Neovim Quicklist (and to make use of the autowrite feature)

If you add the following lines to ~/.config/nvim/ftplugin/scala.vim

" Make that calling make automatically save the change in your buffers
setlocal autowrite

setlocal makeprg=scalac\ -classpath\ .
setlocal errorformat=%A--\ [%t%n]\ %m:%f:%l:%c\ -%#,%C%\\d%#\ %#\|%.%#,%C%\\d%\\+\ error%.%#

I had to transform the scalac output with sed (| sed s/\x1B\[[0-9]\+m//g) to remove the color escape characters for the errorformat to work.

And the following line in your init.vim:

nnoremap <F7> :make %<CR>
nnoremap <C-F5> :terminal scala -classpath . %:r<CR>