Support documentation window scrolling

lua/cmp/config/default.lua

@@ -29,6 +29,10 @@ return function()
       winhighlight = 'NormalFloat:CmpDocumentation,FloatBorder:CmpDocumentationBorder',
       maxwidth = math.floor((WIDE_HEIGHT * 2) * (vim.o.columns / (WIDE_HEIGHT * 2 * 16 / 9))),
       maxheight = math.floor(WIDE_HEIGHT * (WIDE_HEIGHT / vim.o.lines)),
+      mapping = {
+        ['<C-d>'] = types.cmp.ScrollDirection.Up,
+        ['<C-f>'] = types.cmp.ScrollDirection.Down,
+      }
     },
 
     confirmation = {

lua/cmp/core.lua

@@ -69,6 +69,16 @@ end
 
 ---Keypress handler
 core.on_keymap = function(keys, fallback)
+  -- Documentation scroll
+  if config.get().documentation.mapping[keys] then
+    if config.get().documentation.mapping[keys] == types.cmp.ScrollDirection.Up then
+      core.menu.float:scroll(-4)
+    elseif config.get().documentation.mapping[keys] == types.cmp.ScrollDirection.Down then
+      core.menu.float:scroll(4)
+    end
+    return
+  end
+
   -- Confirm character
   if config.get().confirmation.mapping[keys] then
     local c = config.get().confirmation.mapping[keys]
@@ -110,6 +120,9 @@ core.prepare = function()
   for keys in pairs(config.get().confirmation.mapping) do
     keymap.listen(keys, core.on_keymap)
   end
+  for keys in pairs(config.get().documentation.mapping) do
+    keymap.listen(keys, core.on_keymap)
+  end
 end
 
 ---Check auto-completion

lua/cmp/float.lua

@@ -112,4 +112,21 @@ float.close = async.throttle(
   20
 )
 
+float.scroll = function(self, delta)
+  if self.win and vim.api.nvim_win_is_valid(self.win) then
+    local info = vim.fn.getwininfo(self.win)[1] or {}
+    local buf = vim.api.nvim_win_get_buf(self.win)
+    local top = info.topline or 1
+    top = top + delta
+    top = math.max(top, 1)
+    top = math.min(top, vim.api.nvim_buf_line_count(buf) - info.height + 1)
+
+    vim.defer_fn(function()
+      vim.api.nvim_buf_call(buf, function()
+        vim.cmd('normal! ' .. top .. 'zt')
+      end)
+    end, 0)
+  end
+end
+
 return float

lua/cmp/types/cmp.lua

@@ -17,6 +17,11 @@ cmp.TriggerEvent = {}
 cmp.TriggerEvent.InsertEnter = 'InsertEnter'
 cmp.TriggerEvent.TextChanged = 'TextChanged'
 
+---@alias cmp.ScrollDirection "'up'" | "'down'"
+cmp.ScrollDirection = {}
+cmp.ScrollDirection.Up = 'up'
+cmp.ScrollDirection.Down = 'down'
+
 ---@class cmp.ContextOption
 ---@field public reason cmp.ContextReason|nil
 
@@ -59,6 +64,7 @@ cmp.TriggerEvent.TextChanged = 'TextChanged'
 ---@field public winhighlight string
 ---@field public maxwidth number|nil
 ---@field public maxheight number|nil
+---@field public mapping table<string, cmp.ScrollDirection>
 
 ---@class cmp.ConfirmationConfig
 ---@field public default_behavior cmp.ConfirmBehavior

lua/cmp/utils/keymap.lua

@@ -19,6 +19,21 @@ keymap.t = function(keys)
   return vim.api.nvim_replace_termcodes(keys, true, true, true)
 end
 
+---Escape keymap with <LT>
+keymap.escape = function(keys)
+  local i = 1
+  while i <= #keys do
+    if string.sub(keys, i, i) == '<' then
+      if not vim.tbl_contains({ '<lt>', '<Lt>', '<lT>', '<LT>' }, string.sub(keys, i, i + 3)) then
+        keys = string.sub(keys, 1, i -1) .. '<LT>' ..  string.sub(keys, i + 1)
+        i = i + 3
+      end
+    end
+    i = i + 1
+  end
+  return keys
+end
+
 ---Return vim notation keymapping (simple conversion).
 ---@param s string
 ---@return string
@@ -107,7 +122,7 @@ keymap.listen = setmetatable({
       existing = existing,
       callback = callback,
     })
-    vim.api.nvim_buf_set_keymap(0, 'i', keys, ('v:lua.cmp.utils.keymap.expr("%s")'):format(keys), {
+    vim.api.nvim_buf_set_keymap(0, 'i', keys, ('v:lua.cmp.utils.keymap.expr("%s")'):format(keymap.escape(keys)), {
       expr = true,
       nowait = true,
       noremap = true,
@@ -115,7 +130,6 @@ keymap.listen = setmetatable({
   end,
 })
 misc.set(_G, { 'cmp', 'utils', 'keymap', 'expr' }, function(keys)
-  keys = keymap.to_keymap(keys)
   local bufnr = vim.api.nvim_get_current_buf()
 
   local existing = keymap.listen.cache:get({ bufnr, keys }).existing

lua/cmp/utils/keymap_spec.lua

@@ -10,4 +10,10 @@ describe('keymap', function()
     assert.are.equal(keymap.to_keymap('<CR>'), '<CR>')
     assert.are.equal(keymap.to_keymap('|'), '<Bar>')
   end)
+
+  it('escape', function()
+    assert.are.equal(keymap.escape('<C-d>'), '<LT>C-d>')
+    assert.are.equal(keymap.escape('<C-d><C-f>'), '<LT>C-d><LT>C-f>')
+    assert.are.equal(keymap.escape('<LT>C-d>'), '<LT>C-d>')
+  end)
 end)