fix(treesitter): keep treeview open if source window is still open #31198

Problem: When there is a tree view opened by :InspectTree and the
source buffer is open in multiple windows, closing one of the source
windows will lead to the tree view being closed as well.
Regression by #31181.

Solution: Check how many source windows are open when trying to
quit one. If there are more than one, keep the tree view(s) open.
If the only source window is closed, also close the tree view(s).

fix #31196

runtime/lua/vim/treesitter/dev.lua

@@ -530,12 +530,19 @@ function M.inspect_tree(opts)
   api.nvim_create_autocmd({ 'BufHidden', 'BufUnload', 'QuitPre' }, {
     group = group,
     buffer = buf,
-    once = true,
     callback = function()
+      -- don't close inpector window if source buffer
+      -- has more than one open window
+      if #vim.fn.win_findbuf(buf) > 1 then
+        return
+      end
+
       -- close all tree windows
       for _, window in pairs(vim.fn.win_findbuf(b)) do
         close_win(window)
       end
+
+      return true
     end,
   })
 end