Function for .vimrc to automatically cd to the root of current tab's NERDTree

gistfile1.vim

function! ChangeDirectoryToNERDTreeDir()
	" fallback to parent directory
	let s:path = expand("%:p:h")

	" if NERDTree is present in this tab, cd to it:
	if exists("g:NERDTreeDirNode.GetRootForTab().path._strForCd()")
	    let s:path = g:NERDTreeDirNode.GetRootForTab().path._strForCd()
	endif
	
	" don't do anything if we're restoring a session
	if exists("g:SessionLoad") && g:SessionLoad == 1
		return
	else
		exe "cd" s:path
		" echo s:path
	endif
endfunction 

au WinEnter * call ChangeDirectoryToNERDTreeDir()

?
a:path is readonly.
and ChangeDirectoryToNERDTreeDir() does not have argument path.
did you run this?

Whoops! Not sure how that was working for me, but I updated to use s:path now.

Also, I was getting errors when restoring from a session so there's an additional check for that as well.