feat: allow more dynamic output

refer: #2138

autoload/vimtex/compiler.vim

@@ -60,10 +60,6 @@ function! vimtex#compiler#callback(status) abort " {{{1
 
   let b:vimtex.compiler.status = a:status
 
-  if exists('s:output')
-    call s:output.update()
-  endif
-
   if a:status == 1
     if exists('#User#VimtexEventCompiling')
       doautocmd <nomodeline> User VimtexEventCompiling
@@ -152,77 +148,25 @@ endfunction
 
 " }}}1
 function! vimtex#compiler#output() abort " {{{1
-  let l:file = get(b:vimtex.compiler, 'output', '')
-  if empty(l:file)
+  if !exists('b:vimtex.compiler.output')
+        \ || !filereadable(b:vimtex.compiler.output)
     call vimtex#log#warning('No output exists!')
     return
   endif
 
-  " If window already open, then go there
+  " If relevant output is open, then reuse it
   if exists('s:output')
-    if bufwinnr(l:file) == s:output.winnr
-      execute s:output.winnr . 'wincmd w'
+    if s:output.name ==# a:file
+      if bufwinnr(a:file) == s:output.winnr
+        execute s:output.winnr . 'wincmd w'
+      endif
       return
     else
       call s:output.destroy()
     endif
   endif
 
-  " Create new output window
-  silent execute 'split' l:file
-
-  " Create the output object
-  let s:output = {}
-  let s:output.name = l:file
-  let s:output.bufnr = bufnr('%')
-  let s:output.winnr = bufwinnr('%')
-  function! s:output.update() dict abort
-    if bufwinnr(self.name) != self.winnr
-      return
-    endif
-
-    if mode() ==? 'v' || mode() ==# "\<c-v>"
-      return
-    endif
-
-    " Go to last line of file if it is not the current window
-    if bufwinnr('%') != self.winnr
-      let l:return = bufwinnr('%')
-      execute 'keepalt' self.winnr . 'wincmd w'
-      edit
-      normal! Gzb
-      execute 'keepalt' l:return . 'wincmd w'
-      redraw
-    endif
-  endfunction
-  function! s:output.destroy() dict abort
-    autocmd! vimtex_output_window
-    augroup! vimtex_output_window
-    unlet s:output
-  endfunction
-
-  " Better automatic update
-  augroup vimtex_output_window
-    autocmd!
-    autocmd BufDelete <buffer> call s:output.destroy()
-    autocmd BufEnter     *     call s:output.update()
-    autocmd FocusGained  *     call s:output.update()
-    autocmd CursorHold   *     call s:output.update()
-    autocmd CursorHoldI  *     call s:output.update()
-    autocmd CursorMoved  *     call s:output.update()
-    autocmd CursorMovedI *     call s:output.update()
-  augroup END
-
-  " Set some mappings
-  nnoremap <silent><buffer><nowait> q :bwipeout<cr>
-  if has('nvim') || has('gui_running')
-    nnoremap <silent><buffer><nowait> <esc> :bwipeout<cr>
-  endif
-
-  " Set some buffer options
-  setlocal autoread
-  setlocal nomodifiable
-  setlocal bufhidden=wipe
+  call s:output_factory.create(b:vimtex.compiler.output)
 endfunction
 
 " }}}1
@@ -365,6 +309,78 @@ endfunction
 " }}}1
 
 
+let s:output_factory = {}
+function! s:output_factory.create(file) dict abort " {{{1
+  silent execute 'split' a:file
+  setlocal autoread
+  setlocal nomodifiable
+  setlocal bufhidden=wipe
+
+  nnoremap <silent><buffer><nowait> q :bwipeout<cr>
+  if has('nvim') || has('gui_running')
+    nnoremap <silent><buffer><nowait> <esc> :bwipeout<cr>
+  endif
+
+  let s:output = deepcopy(self)
+  unlet s:output.create
+
+  let s:output.name = a:file
+  let s:output.bufnr = bufnr('%')
+  let s:output.winnr = bufwinnr('%')
+  let s:output.timer = timer_start(150,
+        \ {_ -> s:output.update()},
+        \ {'repeat': -1})
+
+  augroup vimtex_output_window
+    autocmd!
+    autocmd BufDelete <buffer> call s:output.destroy()
+    autocmd BufEnter     *     call s:output.update()
+    autocmd FocusGained  *     call s:output.update()
+    autocmd CursorHold   *     call s:output.update()
+    autocmd CursorHoldI  *     call s:output.update()
+    autocmd CursorMoved  *     call s:output.update()
+    autocmd CursorMovedI *     call s:output.update()
+  augroup END
+endfunction
+
+" }}}1
+function! s:output_factory.update() dict abort " {{{1
+  if bufwinnr(self.name) != self.winnr
+    let self.winnr = bufwinnr(self.name)
+  endif
+
+  if mode() ==? 'v' || mode() ==# "\<c-v>"
+    return
+  endif
+
+  let l:swap = bufwinnr('%') != self.winnr
+  if l:swap
+    let l:return = bufwinnr('%')
+    execute 'keepalt' self.winnr . 'wincmd w'
+  endif
+
+  " Reload content with :edit
+  edit
+
+  if l:swap
+    " Go to last line of file if it is not the current window
+    normal! Gzb
+    execute 'keepalt' l:return . 'wincmd w'
+    redraw
+  endif
+endfunction
+
+" }}}1
+function! s:output_factory.destroy() dict abort " {{{1
+  call timer_stop(self.timer)
+  autocmd! vimtex_output_window
+  augroup! vimtex_output_window
+  unlet s:output
+endfunction
+
+" }}}1
+
+
 " {{{1 Initialize module
 
 if !g:vimtex_compiler_enabled | finish | endif

autoload/vimtex/compiler/_template.vim

@@ -145,12 +145,13 @@ function! s:compiler.start(...) abort dict " {{{1
   if self.continuous
     call vimtex#log#info('Compiler started in continuous mode'
           \ . (a:0 > 0 ? ' (single shot)' : ''))
-    if exists('#User#VimtexEventCompileStarted')
-      doautocmd <nomodeline> User VimtexEventCompileStarted
-    endif
   else
     call vimtex#log#info('Compiler started in background!')
   endif
+
+  if exists('#User#VimtexEventCompileStarted')
+    doautocmd <nomodeline> User VimtexEventCompileStarted
+  endif
 endfunction
 
 " }}}1