nvim: Miscellaneous cleanups & improvements

Signed-off-by: Sanchayan Maity <maitysanchayan@gmail.com>

nvim/.config/nvim/init.vim

@@ -117,7 +117,7 @@ let maplocalleader=","
 
 set colorcolumn=80      " Highlight 80th column
 set laststatus=2        " Always show status bar
-set updatetime=500      " Let plugins show effects after 500ms
+set updatetime=300      " Let plugins show effects after 500ms
 set mouse-=a            " Disable mouse click to go to position
 set encoding=utf-8
 set exrc                " Allow loading local .nvimrc files
@@ -147,6 +147,7 @@ set nowritebackup       " only in case you don't want a backup file while editin
 set noswapfile          " no swap files
 set foldmethod=syntax   " Create folds based on files syntax
 set nofoldenable        " Open folds by default
+set undofile            " Enable undo persistence across sessions
 
 " Wild menu
 set wildmenu
@@ -466,6 +467,8 @@ augroup END
 augroup terminal_job
 	au!
 	au TermOpen * setlocal statusline=%{b:terminal_job_id}
+	au TermOpen * startinsert
+	au TermOpen * setlocal listchars= nonumber norelativenumber
 augroup END
 
 augroup indentation_defaults
@@ -473,10 +476,10 @@ augroup indentation_defaults
 	au BufRead,BufNewFile *.c set noexpandtab
 	au BufRead,BufNewFile *.h set noexpandtab
 	au BufRead,BufNewFile Makefile* set noexpandtab
-	au BufNewFile,BufRead *.vim setlocal noet ts=4 sw=4 sts=4
+	au BufRead,BufNewFile *.vim setlocal noet ts=4 sw=4 sts=4
-	au BufNewFile,BufRead *.txt setlocal noet ts=4 sw=4
+	au BufRead,BufNewFile *.txt setlocal noet ts=4 sw=4
-	au BufNewFile,BufRead *.lua setlocal noet ts=4 sw=4 sts=4
+	au BufRead,BufNewFile *.lua setlocal noet ts=4 sw=4 sts=4
-	au BufNewFile,BufRead *.py setlocal tabstop=4 softtabstop=4 shiftwidth=4 textwidth=80 smarttab expandtab
+	au BufRead,BufNewFile *.py setlocal tabstop=4 softtabstop=4 shiftwidth=4 textwidth=80 smarttab expandtab
 	au BufRead,BufNewFile */gst-*/*.[ch] set et sw=2
 	au BufRead,BufNewFile */gstreamer-*/*.[ch] set et sw=2
 	au BufRead,BufNewFile */pulseaudio/*.[ch] set et sw=4 tw=128
@@ -679,7 +682,7 @@ function! Cscope(option, query)
                 \             '--multi', '--bind', 'alt-a:select-all,alt-d:deselect-all',
                 \             '--color', 'info:144,prompt:161,spinner:135,pointer:135,marker:118',
                 \             '--color', 'fg:252,bg:233,hl:67,fg+:252,bg+:235,hl+:81'],
-                \ 'window': 'call FloatingFZF()'
+                \ 'window': 'call CreateCentredFloatingWindow()'
                 \ }
     function! opts.sink(lines)
         let data = split(a:lines)
@@ -726,24 +729,29 @@ function! NvimGdbNoTKeymaps()
 endfunction
 
 let $FZF_DEFAULT_OPTS='--layout=reverse'
-let g:fzf_layout = { 'window': 'call FloatingFZF()' }
+let g:fzf_layout = { 'window': 'call CreateCentredFloatingWindow()' }
-function! FloatingFZF()
+" Stolen from https://github.com/camspiers/dotfiles/blob/master/files/.config/nvim/init.vim
-    let buf = nvim_create_buf(v:false, v:true)
+function! CreateCentredFloatingWindow()
-    let height = float2nr(&lines * 0.4)
 	let width = float2nr(&columns * 0.8)
-    let horizontal = float2nr((&columns - width) / 2)
+	let height = float2nr(&lines * 0.4)
-    let vertical = float2nr((&columns - width) / 2)
+	let top = ((&lines - height) / 2) - 1
+	let left = (&columns - width) / 2
+	let opts = {'relative': 'editor', 'row': top, 'col': left, 'width': width, 'height': height, 'style': 'minimal'}
 
-    let opts = {
+	let top = "╭" . repeat("─", width - 2) . "╮"
-        \ 'relative': 'editor',
+	let mid = "│" . repeat(" ", width - 2) . "│"
-        \ 'row': vertical,
+	let bot = "╰" . repeat("─", width - 2) . "╯"
-        \ 'col': horizontal,
+	let lines = [top] + repeat([mid], height - 2) + [bot]
-        \ 'width': width,
+	let s:buf = nvim_create_buf(v:false, v:true)
-        \ 'height': height
+	call nvim_buf_set_lines(s:buf, 0, -1, v:true, lines)
-        \ }
+	call nvim_open_win(s:buf, v:true, opts)
-
+	set winhl=Normal:Floating
-    " open the new window, floating, and enter to it
+	let opts.row += 1
-    call nvim_open_win(buf, v:true, opts)
+	let opts.height -= 2
+	let opts.col += 2
+	let opts.width -= 4
+	call nvim_open_win(nvim_create_buf(v:false, v:true), v:true, opts)
+	au BufWipeout <buffer> exe 'bw '.s:buf
 endfunction
 
 function! s:incsearch_config(...) abort