Daniel Griffen has implemented a Rust extension for Visual Studio (nb, not Visual Studio Code).
It is early in development, but already supports all the core functionality (code completion, goto def, renaming, etc). If your're a Visual Studio user, try it out and let us know what you think!
Unfortunately I have no information on if or when the extension will be available for Mac. VS for Mac is a bit of a misnomer, It was originally Xamarin Studio and was re-branded after the acquisition by Microsoft. Currently there is little to no interoperability between Visual Studio and Visual Studio for Mac.
The plugin tells me "required components not installed" with an "Install" button. When I click the button, it now tells me "could not install one of the required rls components". Any ideas? Should I open an issue somewhere? Should I start a new thread?
For anyone interested: I figured it out. I had rls installed via rustup before I downloaded the plugin. When I uninstalled rls and then clicked the Install button, the plugin got rls and started working correctly.