fix: fix failure to resize match listing on VimResized

I noticed we're only getting one callback (ie. for the prompt but not
for the match listing). Fix that by not doing a buffer-local autocmd.

Next problem: the `WinClosed` event doesn't fire reliably, or if it
does, `nvim_del_autocmd()` doesn't always work. Not sure which, but it
happens routinely. So, we hack around that with a group that we clear
before bringing up the UI. At worst, a lingering autocmd is going to
hang around until the next time the user uses Command-T.

lua/wincent/commandt/private/ui.lua

@@ -79,6 +79,12 @@ ui.show = function(finder, options)
 
   current_window = vim.api.nvim_get_current_win()
 
+  -- Work around an autocommand bug. We don't reliably get `WinClosed` events,
+  -- or if we do, our call to `nvim_del_autocmd()` doesn't always clean up for
+  -- us. So, we add some window-related autocommands to a group which we always
+  -- reset every time we show a new UI.
+  vim.api.nvim_create_augroup('CommandTWindow', { clear = true })
+
   match_listing = MatchListing.new({
     border = options.match_listing.border,
     height = options.height,

lua/wincent/commandt/private/window.lua

@@ -91,6 +91,7 @@ function Window.new(options)
     _on_resize = options.on_resize,
     _padded_title = options.title ~= '' and (' ' .. options.title .. ' ') or '',
     _prompt = options.prompt,
+    _resize_autocmd = nil,
     _selection_highlight = options.selection_highlight,
     _title = options.title,
     _title_buffer = nil,
@@ -246,15 +247,15 @@ function Window:show()
         callback = callback,
       })
     end
-    vim.api.nvim_create_autocmd('VimResized', {
-      buffer = self._main_buffer,
+    self._resize_autocmd = vim.api.nvim_create_autocmd('VimResized', {
       callback = function()
-        -- This will reposition title, too, so no need for a separate autocmd.
+        -- One autocmd will handle both title and main repositioning.
         self:_reposition()
         if self._on_resize then
           self._on_resize()
         end
       end,
+      group = vim.api.nvim_create_augroup('CommandTWindow', { clear = false }),
     })
     vim.api.nvim_create_autocmd('BufWipeout', {
       buffer = self._main_buffer,
@@ -296,6 +297,10 @@ function Window:show()
           vim.api.nvim_win_close(self._title_window, true)
           self._title_window = nil
         end
+        if self._resize_autocmd ~= nil then
+          vim.api.nvim_del_autocmd(self._resize_autocmd)
+          self._resize_autocmd = nil
+        end
         if self._on_close then
           self._on_close()
         end