lsp autocomplete missing fn args on rust trait impl 
lsp autocomplete missing fn args on rust trait impl , as blow
<img width="911" alt="Screen Shot 2021-11-04 at 15 21 52" src="https://user-images.githubusercontent.com/16577489/140273326-077aae4d-59e3-4cf2-ac75-ef0a530672d4.png">

