fix: doc scrollbar render (#724)

* fix(scrollbar): update doc scrollbar after scroll doc

* fix(scrollbar): fix doc scrollbar position after scroll

* fix(scrollbar): make sure scrollbar thumb wouldn't over the border

* perf(scrollbar): trigger doc update by fix emitter closure

* doc: update scrollbar line calculating comment

* feat: rework scrollbar updates

---------

Co-authored-by: Liam Dyer <[email protected]>

lua/blink/cmp/completion/windows/documentation.lua

@@ -30,12 +30,13 @@ local docs = {
     scrollbar = win_config.scrollbar,
     wrap = true,
     filetype = 'blink-cmp-documentation',
+    scrolloff = 0,
   }),
   last_context_id = nil,
   auto_show_timer = vim.uv.new_timer(),
 }
 
-menu.position_update_emitter:on(docs.update_position)
+menu.position_update_emitter:on(function() docs.update_position() end)
 menu.close_emitter:on(function()
   docs.win:close()
   docs.auto_show_timer:stop()
@@ -96,33 +97,38 @@ function docs.show_item(context, item)
 
       if menu.win:get_win() then
         docs.win:open()
-        vim.api.nvim_win_set_cursor(docs.win:get_win(), { 1, 0 }) -- reset scroll
+        docs.win:set_cursor({ 1, 0 }) -- reset scroll
         docs.update_position()
       end
     end)
     :catch(function(err) vim.notify(err, vim.log.levels.ERROR, { title = 'blink.cmp' }) end)
 end
 
+-- TODO: compensate for wrapped lines
 function docs.scroll_up(amount)
   local winnr = docs.win:get_win()
-  local top_line = math.max(1, vim.fn.line('w0', winnr) - 1)
+  if winnr == nil then return end
+
+  local top_line = math.max(1, vim.fn.line('w0', winnr))
   local desired_line = math.max(1, top_line - amount)
 
-  vim.api.nvim_win_set_cursor(docs.win:get_win(), { desired_line, 0 })
+  docs.win:set_cursor({ desired_line, 0 })
 end
 
+-- TODO: compensate for wrapped lines
 function docs.scroll_down(amount)
   local winnr = docs.win:get_win()
+  if winnr == nil then return end
+
   local line_count = vim.api.nvim_buf_line_count(docs.win:get_buf())
-  local bottom_line = math.max(1, vim.fn.line('w$', winnr) + 1)
+  local bottom_line = math.max(1, vim.fn.line('w$', winnr))
   local desired_line = math.min(line_count, bottom_line + amount)
 
-  vim.api.nvim_win_set_cursor(docs.win:get_win(), { desired_line, 0 })
+  docs.win:set_cursor({ desired_line, 0 })
 end
 
 function docs.update_position()
   if not docs.win:is_open() or not menu.win:is_open() then return end
-  local winnr = docs.win:get_win()
 
   docs.win:update_size()
 
@@ -163,16 +169,16 @@ function docs.update_position()
   end
 
   -- set width and height based on available space
-  vim.api.nvim_win_set_height(docs.win:get_win(), pos.height)
-  vim.api.nvim_win_set_width(docs.win:get_win(), pos.width)
+  docs.win:set_height(pos.height)
+  docs.win:set_width(pos.width)
 
   -- set position based on provided direction
 
   local height = docs.win:get_height()
   local width = docs.win:get_width()
 
   local function set_config(opts)
-    vim.api.nvim_win_set_config(winnr, { relative = 'win', win = menu_winnr, row = opts.row, col = opts.col })
+    docs.win:set_win_config({ relative = 'win', win = menu_winnr, row = opts.row, col = opts.col })
   end
   if pos.direction == 'n' then
     if menu_win_is_up then
@@ -214,8 +220,6 @@ function docs.update_position()
       set_config({ row = -menu_border_size.top, col = -width - menu_border_size.left })
     end
   end
-
-  if docs.win.scrollbar then docs.win.scrollbar:update(winnr) end
 end
 
 return docs

lua/blink/cmp/completion/windows/menu.lua

@@ -79,16 +79,12 @@ function menu.close()
 
   menu.win:close()
   menu.close_emitter:emit()
-  menu.redraw_if_needed()
 end
 
 function menu.set_selected_item_idx(idx)
   menu.win:set_option_value('cursorline', idx ~= nil)
   menu.selected_item_idx = idx
-  if menu.win:is_open() then
-    vim.api.nvim_win_set_cursor(menu.win:get_win(), { idx or 1, 0 })
-    menu.redraw_if_needed()
-  end
+  if menu.win:is_open() then menu.win:set_cursor({ idx or 1, 0 }) end
 end
 
 --- TODO: Don't switch directions if the context is the same
@@ -98,7 +94,6 @@ function menu.update_position()
 
   local win = menu.win
   if not win:is_open() then return end
-  local winnr = win:get_win()
 
   win:update_size()
 
@@ -119,37 +114,20 @@ function menu.update_position()
 
   if vim.api.nvim_get_mode().mode == 'c' then
     local cmdline_position = config.cmdline_position()
-    vim.api.nvim_win_set_config(winnr, {
+    win:set_win_config({
       relative = 'editor',
       row = cmdline_position[1] + row,
       col = math.max(cmdline_position[2] + context.bounds.start_col - start_col, 0),
     })
   else
     local cursor_col = context.get_cursor()[2]
     local col = context.bounds.start_col - cursor_col - (context.bounds.length == 0 and 0 or 1) - border_size.left
-    vim.api.nvim_win_set_config(winnr, { relative = 'cursor', row = row, col = col - start_col })
+    win:set_win_config({ relative = 'cursor', row = row, col = col - start_col })
   end
 
-  vim.api.nvim_win_set_height(winnr, pos.height)
-  if win.scrollbar then win.scrollbar:update(winnr) end
+  win:set_height(pos.height)
 
   menu.position_update_emitter:emit()
-  menu.redraw_if_needed()
-end
-
-local redraw_queued = false
---- In cmdline mode, the window won't be redrawn automatically so we redraw ourselves on schedule
-function menu.redraw_if_needed()
-  if vim.api.nvim_get_mode().mode ~= 'c' or menu.win:get_win() == nil then return end
-  if redraw_queued then return end
-
-  -- We redraw on schedule to avoid the cmdline disappearing during redraw
-  -- and to batch multiple redraws together
-  redraw_queued = true
-  vim.schedule(function()
-    redraw_queued = false
-    vim.api.nvim__redraw({ win = menu.win:get_win(), flush = true })
-  end)
 end
 
 return menu

lua/blink/cmp/config/completion/documentation.lua

@@ -37,7 +37,7 @@ local documentation = {
       desired_min_height = 10,
       border = 'padded',
       winblend = 0,
-      winhighlight = 'Normal:BlinkCmpDoc,FloatBorder:BlinkCmpDocBorder',
+      winhighlight = 'Normal:BlinkCmpDoc,FloatBorder:BlinkCmpDocBorder,EndOfBuffer:BlinkCmpDoc',
       scrollbar = true,
       direction_priority = {
         menu_north = { 'e', 'w', 'n', 's' },

lua/blink/cmp/lib/window/init.lua

@@ -1,3 +1,6 @@
+-- TODO: The scrollbar and redrawing logic should be done by wrapping the functions that would
+-- trigger a redraw or update the window
+
 --- @class blink.cmp.WindowOptions
 --- @field min_width? number
 --- @field max_width? number
@@ -16,6 +19,7 @@
 --- @field buf? number
 --- @field config blink.cmp.WindowOptions
 --- @field scrollbar? blink.cmp.Scrollbar
+--- @field redraw_queued boolean
 ---
 --- @field new fun(config: blink.cmp.WindowOptions): blink.cmp.Window
 --- @field get_buf fun(self: blink.cmp.Window): number
@@ -31,8 +35,13 @@
 --- @field get_content_width fun(self: blink.cmp.Window): number
 --- @field get_width fun(self: blink.cmp.Window): number
 --- @field get_cursor_screen_position fun(): { distance_from_top: number, distance_from_bottom: number }
+--- @field set_cursor fun(self: blink.cmp.Window, cursor: number[])
+--- @field set_height fun(self: blink.cmp.Window, height: number)
+--- @field set_width fun(self: blink.cmp.Window, width: number)
+--- @field set_win_config fun(self: blink.cmp.Window, config: table)
 --- @field get_vertical_direction_and_height fun(self: blink.cmp.Window, direction_priority: ("n" | "s")[]): { height: number, direction: 'n' | 's' }?
 --- @field get_direction_with_window_constraints fun(self: blink.cmp.Window, anchor_win: blink.cmp.Window, direction_priority: ("n" | "s" | "e" | "w")[], desired_min_size?: { width: number, height: number }): { width: number, height: number, direction: 'n' | 's' | 'e' | 'w' }?
+--- @field redraw_if_needed fun(self: blink.cmp.Window)
 
 --- @type blink.cmp.Window
 --- @diagnostic disable-next-line: missing-fields
@@ -57,6 +66,7 @@ function win.new(config)
     scrollbar = config.scrollbar,
     filetype = config.filetype,
   }
+  self.redraw_queued = false
 
   if self.config.scrollbar then
     self.scrollbar = require('blink.cmp.lib.window.scrollbar').new({
@@ -111,6 +121,7 @@ function win:open()
   vim.api.nvim_set_option_value('filetype', self.config.filetype, { buf = self.buf })
 
   if self.scrollbar then self.scrollbar:update(self.id) end
+  self:redraw_if_needed()
 end
 
 function win:set_option_value(option, value)
@@ -124,6 +135,7 @@ function win:close()
     self.id = nil
   end
   if self.scrollbar then self.scrollbar:update() end
+  self:redraw_if_needed()
 end
 
 --- Updates the size of the window to match the max width and height of the content/config
@@ -253,6 +265,46 @@ function win.get_cursor_screen_position()
   }
 end
 
+function win:set_cursor(cursor)
+  local winnr = self:get_win()
+  assert(winnr ~= nil, 'Window must be open to set cursor')
+
+  vim.api.nvim_win_set_cursor(winnr, cursor)
+
+  if self.scrollbar then self.scrollbar:update(winnr) end
+  self:redraw_if_needed()
+end
+
+function win:set_height(height)
+  local winnr = self:get_win()
+  assert(winnr ~= nil, 'Window must be open to set height')
+
+  vim.api.nvim_win_set_height(winnr, height)
+
+  if self.scrollbar then self.scrollbar:update(winnr) end
+  self:redraw_if_needed()
+end
+
+function win:set_width(width)
+  local winnr = self:get_win()
+  assert(winnr ~= nil, 'Window must be open to set width')
+
+  vim.api.nvim_win_set_width(winnr, width)
+
+  if self.scrollbar then self.scrollbar:update(winnr) end
+  self:redraw_if_needed()
+end
+
+function win:set_win_config(config)
+  local winnr = self:get_win()
+  assert(winnr ~= nil, 'Window must be open to set window config')
+
+  vim.api.nvim_win_set_config(winnr, config)
+
+  if self.scrollbar then self.scrollbar:update(winnr) end
+  self:redraw_if_needed()
+end
+
 --- Gets the direction with the most space available, prioritizing the directions in the order of the
 --- direction_priority list
 function win:get_vertical_direction_and_height(direction_priority)
@@ -374,4 +426,17 @@ function win:get_direction_with_window_constraints(anchor_win, direction_priorit
   }
 end
 
+--- In cmdline mode, the window won't be redrawn automatically so we redraw ourselves on schedule
+function win:redraw_if_needed()
+  if self.redraw_queued or vim.api.nvim_get_mode().mode ~= 'c' or self:get_win() == nil then return end
+
+  -- We redraw on schedule to avoid the cmdline disappearing during redraw
+  -- and to batch multiple redraws together
+  self.redraw_queued = true
+  vim.schedule(function()
+    self.redraw_queued = false
+    vim.api.nvim__redraw({ win = self:get_win(), flush = true })
+  end)
+end
+
 return win

lua/blink/cmp/lib/window/scrollbar/geometry.lua

@@ -38,6 +38,24 @@ local function get_col_offset(border)
   return 0
 end
 
+--- Gets the starting line, handling line wrapping if enabled
+--- @param target_win number
+--- @param width number
+--- @return number
+local get_content_start_line = function(target_win, width)
+  local start_line = math.max(1, vim.fn.line('w0', target_win))
+  if not vim.wo[target_win].wrap then return start_line end
+
+  local bufnr = vim.api.nvim_win_get_buf(target_win)
+  local wrapped_start_line = 1
+  for _, text in ipairs(vim.api.nvim_buf_get_lines(bufnr, 0, start_line - 1, false)) do
+    -- nvim_buf_get_lines sometimes returns a blob. see hrsh7th/nvim-cmp#2050
+    if vim.fn.type(text) == vim.v.t_blob then text = vim.fn.string(text) end
+    wrapped_start_line = wrapped_start_line + math.max(1, math.ceil(vim.fn.strdisplaywidth(text) / width))
+  end
+  return wrapped_start_line
+end
+
 --- @param target_win number
 --- @return { should_hide: boolean, thumb: blink.cmp.ScrollbarGeometry, gutter: blink.cmp.ScrollbarGeometry }
 function M.get_geometry(target_win)
@@ -47,10 +65,14 @@ function M.get_geometry(target_win)
   local zindex = config.zindex
 
   local buf_height = get_win_buf_height(target_win)
-  local start_line = math.max(1, vim.fn.line('w0', target_win))
-  local pct = (start_line - 1) / (buf_height - height)
   local thumb_height = math.max(1, math.floor(height * height / buf_height + 0.5) - 1)
+
+  local start_line = get_content_start_line(target_win, width or 1)
+
+  local pct = (start_line - 1) / (buf_height - height)
   local thumb_offset = math.floor((pct * (height - thumb_height)) + 0.5)
+  thumb_height = thumb_offset + thumb_height > height and height - thumb_offset or thumb_height
+  thumb_height = math.max(1, thumb_height)
 
   local common_geometry = {
     width = 1,

lua/blink/cmp/lib/window/scrollbar/init.lua

@@ -7,12 +7,9 @@
 
 --- @class blink.cmp.Scrollbar
 --- @field win blink.cmp.ScrollbarWin
---- @field autocmd? number
---- @field target_win? number
 ---
 --- @field new fun(opts: blink.cmp.ScrollbarConfig): blink.cmp.Scrollbar
 --- @field is_visible fun(self: blink.cmp.Scrollbar): boolean
---- @field is_mounted fun(self: blink.cmp.Scrollbar): boolean
 --- @field update fun(self: blink.cmp.Scrollbar, target_win: number | nil)
 
 --- @type blink.cmp.Scrollbar
@@ -27,8 +24,6 @@ end
 
 function scrollbar:is_visible() return self.win:is_visible() end
 
-function scrollbar:is_mounted() return self.autocmd ~= nil end
-
 function scrollbar:update(target_win)
   if target_win == nil or not vim.api.nvim_win_is_valid(target_win) then return self.win:hide() end
 

lua/blink/cmp/lib/window/scrollbar/win.lua

@@ -14,7 +14,10 @@
 --- @field hide_gutter fun(self: blink.cmp.ScrollbarWin)
 --- @field hide fun(self: blink.cmp.ScrollbarWin)
 --- @field _make_win fun(self: blink.cmp.ScrollbarWin, geometry: blink.cmp.ScrollbarGeometry, hl_group: string): number
+--- @field redraw_if_needed fun(self: blink.cmp.ScrollbarWin)
 
+--- @type blink.cmp.ScrollbarWin
+--- @diagnostic disable-next-line: missing-fields
 local scrollbar_win = {}
 
 function scrollbar_win.new(opts) return setmetatable(opts, { __index = scrollbar_win }) end

lua/blink/cmp/signature/window.lua

@@ -153,8 +153,6 @@ function signature.update_position()
   else
     vim.api.nvim_win_set_config(winnr, { relative = 'cursor', row = pos.direction == 's' and 1 or -height, col = 0 })
   end
-
-  if win.scrollbar then win.scrollbar:update(winnr) end
 end
 
 return signature