fix(highlight): fix invalid highlight for doc separator (#449)

Also add default highlight in default config and README

Author: tim3nd

README.md

@@ -687,6 +687,7 @@ MiniDeps.add({
 | `BlinkCmpGhostText` | Comment | Preview item with ghost text  |
 | `BlinkCmpDoc` | NormalFloat | The documentation window |
 | `BlinkCmpDocBorder` | NormalFloat | The documentation window border |
+| `BlinkCmpDocSeparator` | NormalFloat | The documentation separator between doc and detail |
 | `BlinkCmpDocCursorLine` | Visual | The documentation window cursor line |
 | `BlinkCmpSignatureHelp` | NormalFloat | The signature help window |
 | `BlinkCmpSignatureHelpBorder` | NormalFloat | The signature help window border |

lua/blink/cmp/highlights.lua

@@ -33,6 +33,7 @@ function highlights.setup()
 
   set_hl('BlinkCmpDoc', { link = 'NormalFloat' })
   set_hl('BlinkCmpDocBorder', { link = 'NormalFloat' })
+  set_hl('BlinkCmpDocSeparator', { link = 'NormalFloat' })
   set_hl('BlinkCmpDocCursorLine', { link = 'Visual' })
 
   set_hl('BlinkCmpSignatureHelp', { link = 'NormalFloat' })

lua/blink/cmp/lib/window/docs.lua

@@ -39,10 +39,8 @@ function docs.render_detail_and_documentation(bufnr, detail, documentation, max_
   -- Only add the separator if there are documentation lines (otherwise only display the detail)
   if #detail_lines > 0 and #doc_lines > 0 then
     vim.api.nvim_buf_set_extmark(bufnr, highlight_ns, #detail_lines, 0, {
-      virt_text = { { string.rep('─', max_width) } },
+      virt_text = { { string.rep('─', max_width), 'BlinkCmpDocSeparator' } },
       virt_text_pos = 'overlay',
-      hl_eol = true,
-      hl_group = 'BlinkCmpDocDetail',
     })
   end