Use balloon hovers instead of cursorhold hovers to show documents

autoload/youcompleteme.vim

@@ -169,7 +169,7 @@ function! youcompleteme#Enable()
     " supported, enable it.
     let s:resolve_completions = s:RESOLVE_ON_DEMAND
   elseif require_resolve
-    " The preview window or info popup is enalbed - request the server
+    " The preview window or info popup is enabled - request the server
     " pre-resolves completion items
     let s:resolve_completions = s:RESOLVE_UP_FRONT
   else
@@ -709,19 +709,28 @@ endfunction
 
 
 function! s:EnableAutoHover()
-  if g:ycm_auto_hover ==# 'CursorHold' && s:enable_hover
-    augroup YcmBufHover
-      autocmd! * <buffer>
-      autocmd CursorHold <buffer> call s:Hover()
-    augroup END
+  if s:enable_hover
+    if has( 'balloon_eval' )
+      set ballooneval
+    endif
+    if has( 'balloon_eval_term' )
+      set balloonevalterm
+    endif
+    if exists( '+balloonexpr' ) && empty( &balloonexpr )
+      set balloonexpr=youcompleteme#hover()
+    endif
   endif
 endfunction
 
 
 function! s:DisableAutoHover()
-  augroup YcmBufHover
-    autocmd! * <buffer>
-  augroup END
+  call popup_clear()
+  if has( 'balloon_eval' )
+    set noballooneval
+  endif
+  if has( 'balloon_eval_term' )
+    set noballoonevalterm
+  endif
 endfunction
 
 
@@ -1245,7 +1254,7 @@ function! s:PollResolve( item, ... )
 
   " Note we re-use the 'completion' request for resolves. This prevents us
   " sending a completion request and a resolve request at the same time, as
-  " resolve requests re-use the requset data from the last completion request
+  " resolve requests re-use the request data from the last completion request
   " and it must not change.
   " We also re-use the poller, so that any new completion request effectively
   " cancels this poller.
@@ -1258,9 +1267,12 @@ function! s:PollResolve( item, ... )
   call s:ShowInfoPopup( completion_item )
 endfunction
 
+set completepopup+=align:menu
+
 function! s:ShowInfoPopup( completion_item )
   let id = popup_findinfo()
-  if id
+  if id && !empty( a:completion_item.info )
+    call popup_setoptions( id, { 'highlight': 'Pmenu' } )
     call popup_settext( id, split( a:completion_item.info, '\n' ) )
     call popup_show( id )
   endif
@@ -1584,11 +1596,10 @@ function! s:ForceCompileAndDiagnostics()
 endfunction
 
 
-if exists( '*popup_atcursor' )
-  function s:Hover()
+if exists( '*popup_atcursor' ) && exists( '*popup_beval' )
+  function s:Hover( hover_type )
     if !py3eval( 'ycm_state.NativeFiletypeCompletionUsable()' )
       " Cancel the autocommand if it happens to have been set
-      call s:DisableAutoHover()
       return
     endif
 
@@ -1618,14 +1629,28 @@ if exists( '*popup_atcursor' )
       return
     endif
 
-    call youcompleteme#GetCommandResponseAsync(
-          \ function( 's:ShowHoverResult' ),
-          \ b:ycm_hover.command )
+    let s:hover_syntax = b:ycm_hover.syntax
+    if a:hover_type == 'cursorhold'
+      let s:hover_pos = screenpos( win_getid(), line( '.' ), col( '.' ) )
+      let s:HoverPopupFunc = function( 'popup_atcursor' )
+      call youcompleteme#GetCommandResponseAsync(
+            \ function( 's:ShowHoverResult' ),
+            \ b:ycm_hover.command )
+    elseif a:hover_type == 'balloon'
+      let s:hover_pos = screenpos( v:beval_winid, v:beval_lnum, v:beval_col )
+      let s:HoverPopupFunc = function( 'popup_beval' )
+      call youcompleteme#GetCommandResponseAsync(
+            \ function( 's:ShowHoverResult' ),
+            \ b:ycm_hover.command,
+            \ '--bufnr=' . v:beval_bufnr,
+            \ '--line_num=' . v:beval_lnum,
+            \ '--column_num=' . v:beval_col )
+    endif
   endfunction
 
 
   function! s:ShowHoverResult( response )
-    call popup_hide( s:cursorhold_popup )
+    call popup_close( s:cursorhold_popup )
 
     if empty( a:response )
       return
@@ -1637,56 +1662,72 @@ if exists( '*popup_atcursor' )
     "
     " Find the longest line (FIXME: probably doesn't work well for multi-byte)
     let lines = split( a:response, "\n" )
-    let len = max( map( copy( lines ), "len( v:val )" ) )
+    let len = max( map( copy( lines ), "strdisplaywidth( v:val )" ) )
 
+    let col = s:hover_pos.col
     let wrap = 0
-    let col = 'cursor'
-
-    " max width is screen columns minus x padding (2)
-    if len >= (&columns - 2)
-      " There's at least one line > our max - enable word wrap and draw the
+    let border  = { 'above': 1, 'right': 1, 'below': 1, 'left': 1 }
+    let padding = { 'above': 0, 'right': 1, 'below': 0, 'left': 1 }
+    let left_right_reserve  = border.left  + border.right + padding.left  + padding.right
+    let above_below_reserve = border.above + border.below + padding.above + padding.below
+    let maxheight = max( [ s:hover_pos.row - 1, &lines - s:hover_pos.row ] ) - above_below_reserve
+
+    " max width is screen columns minus border and padding
+    let maxwidth = &columns - left_right_reserve
+    let minwidth = min( [ len, maxwidth ] )
+    if len >= maxwidth
+      " There's at least one line >= our max - enable word wrap and draw the
       " popup at the leftmost column
       let col = 1
       let wrap = 1
     endif
 
-    let s:cursorhold_popup = popup_atcursor(
+    let s:cursorhold_popup = s:HoverPopupFunc(
           \   lines,
           \   {
-          \     'col': col,
-          \     'wrap': wrap,
-          \     'padding': [ 0, 1, 0, 1 ],
-          \     'moved': 'word',
-          \     'maxwidth': &columns,
-          \     'close': 'click',
-          \     'fixed': 0,
+          \     'col'      : col,
+          \     'wrap'     : wrap,
+          \     'border'   : [ border.above,  border.right,  border.below,  border.left  ],
+          \     'padding'  : [ padding.above, padding.right, padding.below, padding.left ],
+          \     'maxheight': maxheight,
+          \     'maxwidth' : maxwidth,
+          \     'minwidth' : minwidth,
+          \     'close'    : 'click',
+          \     'fixed'    : 0,
+          \     'resize'   : 1,
+          \     'drag'     : 1
           \   }
           \ )
+    if popup_getpos( s:cursorhold_popup ).scrollbar
+      call popup_setoptions( s:cursorhold_popup,
+                           \ { 'maxwidth': maxwidth - 1 } )
+    endif
     call setbufvar( winbufnr( s:cursorhold_popup ),
                             \ '&syntax',
-                            \ b:ycm_hover.syntax )
+                            \ s:hover_syntax )
   endfunction
 
 
   function! s:ToggleHover()
     let pos = popup_getpos( s:cursorhold_popup )
     if !empty( pos ) && pos.visible
-      call popup_hide( s:cursorhold_popup )
+      call popup_close( s:cursorhold_popup )
       let s:cursorhold_popup = -1
-
-      " Diable the auto-trigger until the next cursor movement.
-      call s:DisableAutoHover()
-      augroup YCMHover
-        autocmd! CursorMoved <buffer>
-        autocmd CursorMoved <buffer> call s:EnableAutoHover()
-      augroup END
     else
-      call s:Hover()
+      call s:Hover( 'cursorhold' )
     endif
   endfunction
 
   let s:enable_hover = 1
   nnoremap <silent> <plug>(YCMHover) :<C-u>call <SID>ToggleHover()<CR>
+  nnoremap <silent> <plug>(YCMHoverON) :<C-u>call <SID>EnableAutoHover()<CR>
+  nnoremap <silent> <plug>(YCMHoverOFF) :<C-u>call <SID>DisableAutoHover()<CR>
+
+  function! youcompleteme#hover()
+    call win_execute( v:beval_winid, 'call s:Hover( "balloon" )' )
+    return ''
+  endfunction
+
 else
   " Don't break people's mappings if this feature is disabled, just do nothing.
   nnoremap <silent> <plug>(YCMHover) <Nop>

python/ycm/youcompleteme.py

@@ -393,6 +393,12 @@ def _GetCommandRequestArguments( self,
       elif argument.startswith( '--bufnr=' ):
         extra_data[ 'bufnr' ] = int( argument[ len( '--bufnr=' ): ] )
         continue
+      elif argument.startswith( '--line_num=' ):
+        extra_data[ 'line_num' ] = int( argument[ len( '--line_num=' ): ] )
+        continue
+      elif argument.startswith( '--column_num=' ):
+        extra_data[ 'column_num' ] = int( argument[ len( '--column_num=' ): ] )
+        continue
 
       final_arguments.append( argument )