Fix netrw - mapping when in a buffer with no name/file

lua/netrw.lua

@@ -10,10 +10,16 @@ end
 vim.keymap.set('n', '-', function()
   -- Get the filename before invoking netrw
   local filename = vim.fn.expand('%:t')
+  local directory = vim.fn.expand('%:hp')
+
+  if directory == '' then
+    directory = vim.fn.getcwd()
+  end
 
   -- Invoke netrw on the directory containing the current file
-  vim.fn.execute(string.format("edit %s", vim.fn.expand('%:hp')))
+  vim.fn.execute(string.format("edit %s", directory))
 
+  if filename ~= '' then
     -- In the netrw buffer, move the cursor to the first character of filename
     local buffer = vim.api.nvim_get_current_buf()
     local lines = vim.api.nvim_buf_get_lines(buffer, 0, -1, true)
@@ -24,4 +30,5 @@ vim.keymap.set('n', '-', function()
         break
       end
     end
+  end
 end)