1 files changed, 55 insertions, 13 deletions

diff --git a/runtime/lua/vim/lsp/util.lua b/runtime/lua/vim/lsp/util.lua
index ec1131ae1f..325dc044be 100644
--- a/runtime/lua/vim/lsp/util.lua
+++ b/runtime/lua/vim/lsp/util.lua
@@ -18,6 +18,40 @@ end
 
 local M = {}
 
+local default_border = {
+  {"", "NormalFloat"},
+  {"", "NormalFloat"},
+  {"", "NormalFloat"},
+  {" ", "NormalFloat"},
+  {"", "NormalFloat"},
+  {"", "NormalFloat"},
+  {"", "NormalFloat"},
+  {" ", "NormalFloat"},
+}
+
+--@private
+-- Check the border given by opts or the default border for the additional
+-- size it adds to a float.
+--@returns size of border in height and width
+local function get_border_size(opts)
+  local border = opts and opts.border or default_border
+  local height = 0
+  local width = 0
+
+  if type(border) == 'string' then
+    -- 'single', 'double', etc.
+    height = 2
+    width = 2
+  else
+    height = height + vim.fn.strdisplaywidth(border[2][1])  -- top
+    height = height + vim.fn.strdisplaywidth(border[6][1])  -- bottom
+    width  = width  + vim.fn.strdisplaywidth(border[4][1])  -- right
+    width  = width  + vim.fn.strdisplaywidth(border[8][1])  -- left
+  end
+
+  return { height = height, width = width }
+end
+
 --@private
 local function split_lines(value)
   return split(value, '\n', true)
@@ -856,7 +890,7 @@ function M.make_floating_popup_options(width, height, opts)
   else
     anchor = anchor..'S'
     height = math.min(lines_above, height)
-    row = 0
+    row = -get_border_size(opts).height
   end
 
   if vim.fn.wincol() + width <= api.nvim_get_option('columns') then
@@ -875,6 +909,7 @@ function M.make_floating_popup_options(width, height, opts)
     row = row + (opts.offset_y or 0),
     style = 'minimal',
     width = width,
+    border = opts.border or default_border,
   }
 end
 
@@ -981,27 +1016,20 @@ function M.focusable_preview(unique_name, fn)
   end)
 end
 
---- Trims empty lines from input and pad left and right with spaces
+--- Trims empty lines from input and pad top and bottom with empty lines
 ---
 ---@param contents table of lines to trim and pad
 ---@param opts dictionary with optional fields
----             - pad_left   number of columns to pad contents at left (default 1)
----             - pad_right  number of columns to pad contents at right (default 1)
 ---             - pad_top    number of lines to pad contents at top (default 0)
 ---             - pad_bottom number of lines to pad contents at bottom (default 0)
 ---@return contents table of trimmed and padded lines
-function M._trim_and_pad(contents, opts)
+function M._trim(contents, opts)
   validate {
     contents = { contents, 't' };
     opts = { opts, 't', true };
   }
   opts = opts or {}
-  local left_padding = (" "):rep(opts.pad_left or 1)
-  local right_padding = (" "):rep(opts.pad_right or 1)
   contents = M.trim_empty_lines(contents)
-  for i, line in ipairs(contents) do
-    contents[i] = string.format('%s%s%s', left_padding, line:gsub("\r", ""), right_padding)
-  end
   if opts.pad_top then
     for _ = 1, opts.pad_top do
       table.insert(contents, 1, "")
@@ -1078,8 +1106,8 @@ function M.fancy_floating_markdown(contents, opts)
       end
     end
   end
-  -- Clean up and add padding
-  stripped = M._trim_and_pad(stripped, opts)
+  -- Clean up
+  stripped = M._trim(stripped, opts)
 
   -- Compute size of float needed to show (wrapped) lines
   opts.wrap_at = opts.wrap_at or (vim.wo["wrap"] and api.nvim_win_get_width(0))
@@ -1182,6 +1210,20 @@ function M._make_floating_popup_size(contents, opts)
       width = math.max(line_widths[i], width)
     end
   end
+
+  local border_width = get_border_size(opts).width
+  local screen_width = api.nvim_win_get_width(0)
+  width = math.min(width, screen_width)
+
+  -- make sure borders are always inside the screen
+  if width + border_width > screen_width then
+    width = width - (width + border_width - screen_width)
+  end
+
+  if wrap_at > width then
+    wrap_at = width
+  end
+
   if max_width then
     width = math.min(width, max_width)
     wrap_at = math.min(wrap_at or max_width, max_width)
@@ -1235,7 +1277,7 @@ function M.open_floating_preview(contents, syntax, opts)
   opts = opts or {}
 
   -- Clean up input: trim empty lines from the end, pad
-  contents = M._trim_and_pad(contents, opts)
+  contents = M._trim(contents, opts)
 
   -- Compute size of float needed to show (wrapped) lines
   opts.wrap_at = opts.wrap_at or (vim.wo["wrap"] and api.nvim_win_get_width(0))