Added customizable virtual text prefix

Author: L0stLink

autoload/LanguageClient.vim

@@ -148,14 +148,19 @@ endfunction
 function! s:set_virtual_texts(buf_id, ns_id, line_start, line_end, virtual_texts) abort
     " VirtualText: map with keys line, text and hl_group.
 
+    let l:prefix = s:GetVar('LanguageClient_virtualTextPrefix')
+    if l:prefix is v:null
+        let l:prefix = ''
+    endif
+
     if !exists('*nvim_buf_set_virtual_text')
         return
     endif
 
     call nvim_buf_clear_namespace(a:buf_id, a:ns_id, a:line_start, a:line_end)
 
     for vt in a:virtual_texts
-        call nvim_buf_set_virtual_text(a:buf_id, a:ns_id, vt['line'], [[vt['text'], vt['hl_group']]], {})
+        call nvim_buf_set_virtual_text(a:buf_id, a:ns_id, vt['line'], [[l:prefix . vt['text'], vt['hl_group']]], {})
     endfor
 endfunction
 

doc/LanguageClient.txt

@@ -357,6 +357,16 @@ supported.
 Default: 1 when a floating window is supported, otherwise 0
 Valid Options: 1 | 0
 
+2.27 g:LanguageClient_virtualTextPrefix     *g:LanguageClient_virtualTextPrefix*
+
+When the value is set to a valid string and |g:LanguageClient_useVirtualText| is
+enabled, all virtual text lines are prefixed with the defined string.
+This variable is effective only when the virtual text feature is
+supported.
+
+Default: Empty string ('')
+Valid Options: string
+
 ==============================================================================
 3. Commands                                           *LanguageClientCommands*
 

min-vimrc.vim

@@ -20,5 +20,6 @@ let g:LanguageClient_serverCommands = {
     \ }
 let $RUST_BACKTRACE = 1
 let g:LanguageClient_loggingLevel = 'INFO'
+let g:LanguageClient_virtualTextPrefix = ''
 let g:LanguageClient_loggingFile =  expand('~/.local/share/nvim/LanguageClient.log')
 let g:LanguageClient_serverStderr = expand('~/.local/share/nvim/LanguageServer.log')