[fix]: modify aucmd to properly reference lua module

lua/tidy/init.lua

@@ -0,0 +1,42 @@
+-- MP
+-- These sources did all the work
+--  1. https://vim.fandom.com/wiki/Remove_unwanted_spaces#Automatically_removing_all_trailing_whitespace
+--  2. https://stackoverflow.com/questions/7495932/how-can-i-trim-blank-lines-at-the-end-of-file-in-vim
+
+local M = {}
+
+
+function M.clear_spaces()
+
+    -- get tuple of cursor position before making changes
+    local pos = vim.api.nvim_win_get_cursor( 0 )
+
+    -- delete all whitespace, see source 1
+    vim.cmd[[:%s/\s\+$//e]]
+
+    -- delete all lines at end of buffer, see source 2
+    vim.cmd[[:silent! 0;/^\%(\n*.\)\@!/,$d]]
+
+    -- get row count after line deletion
+    local end_row = vim.api.nvim_buf_line_count( 0 )
+
+
+    --[[
+        if the row value in the original cursor
+        position tuple is greater than the
+        line count after empty line deletion
+        (meaning that the cursor was inside of
+        the empty lines at the end of the file
+        when they were deleted), set the cursor
+        row to the last line
+    ]]
+
+    if pos[1] > end_row then
+        pos[1] = end_row
+    end
+
+    vim.api.nvim_win_set_cursor( 0, pos )
+end
+
+
+return M