fix(win): winopts.split=enew on spash screen (#2210)

Author: ibhagwan

lua/fzf-lua/win.lua

@@ -1070,12 +1070,14 @@ function FzfWin:create()
       vim.cmd(tostring(self.winopts.split))
     end
     local split_bufnr = vim.api.nvim_get_current_buf()
-    assert(self.src_bufnr ~= split_bufnr, "split function should create a new buffer")
     self.fzf_winid = vim.api.nvim_get_current_win()
     if tonumber(self.fzf_bufnr) and vim.api.nvim_buf_is_valid(self.fzf_bufnr) then
       -- Set to fzf bufnr set by `:unhide()`, wipe the new split buf
       utils.win_set_buf_noautocmd(self.fzf_winid, self.fzf_bufnr)
       utils.nvim_buf_delete(split_bufnr, { force = true })
+    elseif self.src_bufnr == split_bufnr then
+      -- "enew" on splash screen doesn't create a new buf
+      self.fzf_bufnr = self:set_tmp_buffer(true)
     else
       self.fzf_bufnr = split_bufnr
     end