add preview for ALEFindReferences

Author: bretello

autoload/ale/references.vim

@@ -67,17 +67,24 @@ function! ale#references#HandleTSServerResponse(conn_id, response) abort
 endfunction
 
 function! ale#references#FormatLSPResponseItem(response_item, options) abort
+    let l:line= a:response_item.range.start.line
+    let l:col = a:response_item.range.start.character
+    let l:filename = ale#util#ToResource(a:response_item.uri)
+    let l:line_text = readfile(l:filename)[l:line]
+
     if get(a:options, 'open_in') is# 'quickfix'
         return {
-        \ 'filename': ale#util#ToResource(a:response_item.uri),
+        \ 'filename': l:filename,
         \ 'lnum': a:response_item.range.start.line + 1,
         \ 'col': a:response_item.range.start.character + 1,
+        \ 'text': l:line_text,
         \}
     else
         return {
-        \ 'filename': ale#util#ToResource(a:response_item.uri),
-        \ 'line': a:response_item.range.start.line + 1,
-        \ 'column': a:response_item.range.start.character + 1,
+        \ 'filename': l:filename,
+        \ 'line': l:line + 1,
+        \ 'column': l:col + 1,
+        \ 'match': l:line_text,
         \}
     endif
 endfunction