Having a hard time dealing with a completion collision

[Doron Behar <doron.behar@xxxxxxxxx>]

I'm using todoman <https://github.com/pimutils/todoman> and it provides
a useful completion for ZSH (I happen to be the writer of it):
<https://github.com/pimutils/todoman/blob/master/contrib/completion/zsh/_todo>

TIL there's another completion file in ZSH's tree that has `#compdef
todo` among other common aliases for it:
https://gitlab.com/zsh-org/zsh/-/blob/5c55b3fb50bbfe602fcfa55fa6258e398ecc6b20/Completion/Unix/Command/_devtodo

I'm using NixOS and this is my `$fpath`:

~/.zsh/comp/tested
~/.zsh/comp/local
/usr/local/share/zsh/site-functions
/nix/store/k9rq1cymsrbfybzgx21c5g851085w0fz-zsh-5.7.1/share/zsh/site-functions
/nix/store/k9rq1cymsrbfybzgx21c5g851085w0fz-zsh-5.7.1/share/zsh/5.7.1/functions
/run/current-system/sw/share/zsh/site-functions
/run/current-system/sw/share/zsh/5.7.1/functions
/run/current-system/sw/share/zsh/vendor-completions
/nix/var/nix/profiles/default/share/zsh/site-functions
/nix/var/nix/profiles/default/share/zsh/5.7.1/functions
/nix/var/nix/profiles/default/share/zsh/vendor-completions
/etc/profiles/per-user/doron/share/zsh/site-functions
/etc/profiles/per-user/doron/share/zsh/5.7.1/functions
/etc/profiles/per-user/doron/share/zsh/vendor-completions
~/.nix-profile/share/zsh/site-functions
~/.nix-profile/share/zsh/5.7.1/functions
~/.nix-profile/share/zsh/vendor-completions

I tried putting the replacement `_todo` file in my first fpath directory
- `~/.zsh/comp/tested/` but surprisingly I still got the failing devtodo
completion loaded instead of the replacement completion.

Assuming I'm not interested in submitting a change to ZSH's source tree,
what would be the best way to handle this collision? My current rather
ugly workaround is to rename the desired completion's file to `_td` and
make it complete `td` instead of `todo` while using the following:

td(){
  todo "$@"
}

An alias doesn't work because ZSH see's there's such an alias and it
loads devtodo's completion just like it would as if there wasn't an
alias.

Help will be appreciated.

Doron.