Autocompletion works when you use zsh and oh-my-zsh. Create the following file in your oh-my-zsh directory
~/.oh-my-zsh/completions/_task.zsh:
#compdef task
_task() {
local -a commands
local tasks=$(task comp_targets)
while IFS= read -r line; do
if [[ -n "$line" ]]; then
commands+=("$line")
fi
done <<< "$tasks"
_describe -t commands 'task commands' commands
}
_task "$@"
Now after running task shorthand, your task commands will get autocompleted.