fix(state): deal with the fact that ModeChanged doesn't always seems to trigger. Fixes #787

Author: folke

lua/which-key/buf.lua

@@ -242,13 +242,6 @@ function M.clear(opts)
       M.bufs[b]:clear(opts)
     end
   end
-  if opts.check ~= false then
-    M.check()
-  end
 end
 
-M.check = Util.debounce(50, function()
-  M.get()
-end)
-
 return M

lua/which-key/mappings.lua

@@ -276,7 +276,7 @@ function M.add(mapping, ret, opts)
     local modes = mapping.mode or { "n" } --[[@as string|string[] ]]
     modes = type(modes) == "string" and vim.split(modes, "") or modes --[[@as string[] ]]
     for _, mode in ipairs(modes) do
-      if mode ~= "v" and mode ~= Util.mapmode({ mode = mode }) then
+      if mode ~= "v" and mode ~= Util.mapmode(mode) then
         M.warn("Invalid mode `" .. mode .. "`", mapping)
       end
       local m = vim.deepcopy(mapping)

lua/which-key/state.lua

@@ -57,10 +57,8 @@ function M.setup()
     callback = function(ev)
       Util.debug(ev.event)
       if ev.event == "RecordingEnter" then
-        Buf.clear({ buf = ev.buf, check = false })
+        Buf.clear({ buf = ev.buf })
         M.stop()
-      else
-        Buf.check()
       end
     end,
   })
@@ -89,16 +87,11 @@ function M.setup()
     return Config.defer(ctx)
   end
 
-  -- this prevents restarting which-key in the same tick
   local cooldown = Util.cooldown()
-
-  -- cache the mode, since it can change outside of ModeChanged events
-  Util.mode = vim.api.nvim_get_mode().mode
-
+  -- this prevents restarting which-key in the same tick
   vim.api.nvim_create_autocmd("ModeChanged", {
     group = group,
     callback = function(ev)
-      Util.mode = vim.api.nvim_get_mode().mode
       Util.trace("ModeChanged(" .. ev.match .. ")")
       local mode = Buf.get()
 
@@ -147,16 +140,32 @@ function M.setup()
     end,
   })
 
+  local current_buf = vim.api.nvim_get_current_buf()
   vim.api.nvim_create_autocmd({ "BufEnter" }, {
     group = group,
     callback = function(ev)
+      current_buf = ev.buf ---@type number
       Util.trace(ev.event .. "(" .. ev.buf .. ")")
       Buf.get()
       Util.trace()
     end,
   })
 
-  Buf.check()
+  -- HACK: ModeChanged does not always trigger, so we need to manually
+  -- check for mode changes. This seems to be due to the usage of `:norm` in autocmds.
+  -- See https://github.com/folke/which-key.nvim/issues/787
+  local last_mode = nil ---@type string?
+  local last_buf = nil ---@type number?
+  local timer = uv.new_timer()
+  timer:start(0, 50, function()
+    local mode = vim.api.nvim_get_mode().mode
+    if mode == last_mode and last_buf == current_buf then
+      return
+    end
+    last_mode = mode
+    last_buf = current_buf
+    vim.schedule(Buf.get)
+  end)
 end
 
 function M.stop()

lua/which-key/util.lua

@@ -17,7 +17,6 @@ M.BS = M.t("<bs>")
 M.EXIT = M.t("<C-\\><C-n>")
 M.LUA_CALLBACK = "\x80\253g"
 M.CMD = "\x80\253h"
-M.mode = "n"
 
 function M.exit()
   vim.api.nvim_feedkeys(M.EXIT, "n", false)
@@ -77,10 +76,9 @@ function M.keys(lhs, opts)
   return ret
 end
 
----@param opts? {mode?: string, cached?: boolean}
-function M.mapmode(opts)
-  opts = opts or {}
-  local mode = opts.mode or (opts.cached ~= false and M.mode) or vim.api.nvim_get_mode().mode
+---@param mode? string
+function M.mapmode(mode)
+  mode = mode or vim.api.nvim_get_mode().mode
   mode = mode:gsub(M.t("<C-V>"), "v"):gsub(M.t("<C-S>"), "s"):lower()
   if mode:sub(1, 2) == "no" then
     return "o"