Show diagnostics in a floating window (#700)

* fix comment

* fix indent

* support diagnostics in a floating window

* doc: add g:lsp_diagnostics_float_{cursor,delay}

* fix vint errors except unused variables

* suppress vint unused variable errors

* lint: use robust operator

.vintrc.yaml

@@ -3,7 +3,7 @@ cmdargs:
 
 policies:
   ProhibitUnusedVariable:
-    enabled: true
+    enabled: false
   ProhibitImplicitScopeVariable:
     enabled: true
   ProhibitNoAbortFunction:

autoload/lsp.vim

@@ -115,7 +115,7 @@ endfunction
 " "exited", "starting", "failed", "running", "not running"
 function! lsp#get_server_status(...) abort
     if a:0 == 0
-        let l:strs = map(keys(s:servers), {k, v -> v . ": " . s:server_status(v)})
+        let l:strs = map(keys(s:servers), {k, v -> v . ': ' . s:server_status(v)})
         return join(l:strs, "\n")
     else
         return s:server_status(a:1)
@@ -189,7 +189,7 @@ function! s:register_events() abort
         if exists('##TextChangedP')
             autocmd TextChangedP * call s:on_text_document_did_change()
         endif
-        if g:lsp_diagnostics_echo_cursor || g:lsp_highlight_references_enabled
+        if g:lsp_diagnostics_echo_cursor || g:lsp_diagnostics_float_cursor || g:lsp_highlight_references_enabled
             autocmd CursorMoved * call s:on_cursor_moved()
         endif
         autocmd BufWinEnter,BufWinLeave,InsertEnter * call lsp#ui#vim#references#clean_references()
@@ -243,6 +243,8 @@ function! s:on_cursor_moved() abort
 
     if g:lsp_diagnostics_echo_cursor
         call lsp#ui#vim#diagnostics#echo#cursor_moved()
+    elseif g:lsp_diagnostics_float_cursor && lsp#ui#vim#output#float_supported()
+        call lsp#ui#vim#diagnostics#float#cursor_moved()
     endif
 
     if g:lsp_highlight_references_enabled
@@ -517,7 +519,7 @@ function! s:ensure_init(buf, server_name, cb) abort
     if has_key(l:server_info, 'capabilities')
         let l:capabilities = l:server_info['capabilities']
     else
-        let l:capabilities = call(g:lsp_get_supported_capabilities[0], [server_info])
+        let l:capabilities = call(g:lsp_get_supported_capabilities[0], [l:server_info])
     endif
 
     let l:request = {
@@ -886,8 +888,8 @@ function! s:add_didchange_queue(buf) abort
     call add(s:didchange_queue, a:buf)
     call lsp#log('s:send_didchange_queue() will be triggered')
     call timer_stop(s:didchange_timer)
-    let lazy = &updatetime > 1000 ? &updatetime : 1000
-    let s:didchange_timer = timer_start(lazy, function('s:send_didchange_queue'))
+    let l:lazy = &updatetime > 1000 ? &updatetime : 1000
+    let s:didchange_timer = timer_start(l:lazy, function('s:send_didchange_queue'))
 endfunction
 
 function! s:send_didchange_queue(...) abort

autoload/lsp/client.vim

@@ -1,5 +1,5 @@
-let s:save_cpo = &cpo
-set cpo&vim
+let s:save_cpo = &cpoptions
+set cpoptions&vim
 
 let s:clients = {} " { client_id: ctx }
 
@@ -268,10 +268,10 @@ function! s:lsp_get_last_request_id(id) abort
 endfunction
 
 function! s:lsp_is_error(obj_or_response) abort
-    let vt = type(a:obj_or_response)
-    if vt == type('')
+    let l:vt = type(a:obj_or_response)
+    if l:vt == type('')
         return len(a:obj_or_response) > 0
-    elseif vt == type({})
+    elseif l:vt == type({})
         return has_key(a:obj_or_response, 'error')
     endif
     return 0
@@ -330,6 +330,6 @@ endfunction
 
 " }}}
 
-let &cpo = s:save_cpo
+let &cpoptions = s:save_cpo
 unlet s:save_cpo
 " vim sw=4 ts=4 et

autoload/lsp/ui/vim.vim

@@ -249,14 +249,14 @@ function! lsp#ui#vim#document_format() abort
 endfunction
 
 function! lsp#ui#vim#stop_server(...) abort
-  let l:name = get(a:000, 0, '')
-  for l:server in lsp#get_whitelisted_servers()
-    if !empty(l:name) && l:server != l:name
-        continue
-    endif
-    echo 'Stopping' l:server 'server ...'
-    call lsp#stop_server(server)
-  endfor
+    let l:name = get(a:000, 0, '')
+    for l:server in lsp#get_whitelisted_servers()
+        if !empty(l:name) && l:server != l:name
+            continue
+        endif
+        echo 'Stopping' l:server 'server ...'
+        call lsp#stop_server(l:server)
+    endfor
 endfunction
 
 function! s:get_selection_pos(type) abort
@@ -439,15 +439,15 @@ function! s:handle_location(ctx, server, type, data) abort "ctx = {counter, list
                 if has_key(l:loc,'viewstart') " showing a locationLink
                     let l:view = l:lines[l:loc['viewstart'] : l:loc['viewend']]
                     call lsp#ui#vim#output#preview(a:server, l:view, {
-                                \   'statusline': ' LSP Peek ' . a:type,
-                                \   'filetype': &filetype
-                                \ })
+                        \   'statusline': ' LSP Peek ' . a:type,
+                        \   'filetype': &filetype
+                        \ })
                 else " showing a location
                     call lsp#ui#vim#output#preview(a:server, l:lines, {
-                                \   'statusline': ' LSP Peek ' . a:type,
-                                \   'cursor': { 'line': l:loc['lnum'], 'col': l:loc['col'], 'align': g:lsp_peek_alignment },
-                                \   'filetype': &filetype
-                                \ })
+                        \   'statusline': ' LSP Peek ' . a:type,
+                        \   'cursor': { 'line': l:loc['lnum'], 'col': l:loc['col'], 'align': g:lsp_peek_alignment },
+                        \   'filetype': &filetype
+                        \ })
                 endif
             endif
         endif
@@ -582,9 +582,9 @@ function! s:get_treeitem_for_tree_hierarchy(Callback, object) dict abort
 endfunction
 
 function! lsp#ui#vim#code_action() abort
-  call lsp#ui#vim#code_action#do({
-      \   'sync': v:false,
-      \   'selection': v:false,
-      \   'query': '',
-      \ })
+    call lsp#ui#vim#code_action#do({
+        \   'sync': v:false,
+        \   'selection': v:false,
+        \   'query': '',
+        \ })
 endfunction

autoload/lsp/ui/vim/diagnostics.vim

@@ -35,7 +35,7 @@ function! lsp#ui#vim#diagnostics#document_diagnostics() abort
     endif
 
     let l:result = []
-    for [l:server_name, l:data] in items(l:diagnostics)
+    for l:data in values(l:diagnostics)
         let l:result += lsp#ui#vim#utils#diagnostics_to_loc_list(l:data)
     endfor
 

autoload/lsp/ui/vim/diagnostics/echo.vim

@@ -1,6 +1,6 @@
 function! lsp#ui#vim#diagnostics#echo#cursor_moved() abort
     if mode() isnot# 'n'
-        " dont' show echo only in normal mode
+        " show echo only in normal mode
         return
     endif
 

autoload/lsp/ui/vim/diagnostics/float.vim

@@ -0,0 +1,32 @@
+function! lsp#ui#vim#diagnostics#float#cursor_moved() abort
+    call s:stop_cursor_moved_timer()
+
+    let l:current_pos = getcurpos()[0:2]
+
+    " use timer to avoid recalculation
+    if !exists('s:last_pos') || l:current_pos != s:last_pos
+        let s:last_pos = l:current_pos
+        let s:cursor_moved_timer = timer_start(g:lsp_diagnostics_float_delay, function('s:float_diagnostics_under_cursor'))
+    endif
+endfunction
+
+function! s:float_diagnostics_under_cursor(...) abort
+    let l:diagnostic = lsp#ui#vim#diagnostics#get_diagnostics_under_cursor()
+    if !empty(l:diagnostic) && has_key(l:diagnostic, 'message')
+        let l:lines = split(l:diagnostic['message'], '\n', 1)
+        call lsp#ui#vim#output#preview('', l:lines, {
+            \   'statusline': ' LSP Diagnostics'
+            \})
+        let s:displaying_message = 1
+    elseif get(s:, 'displaying_message', 0)
+        call lsp#ui#vim#output#closepreview()
+        let s:displaying_message = 0
+    endif
+endfunction
+
+function! s:stop_cursor_moved_timer() abort
+    if exists('s:cursor_moved_timer')
+        call timer_stop(s:cursor_moved_timer)
+        unlet s:cursor_moved_timer
+    endif
+endfunction