I’ve just installed the .NET Core Tooling Preview 1 that was recently released and it has ESLint in it. So now Visual Studio 2015 can point out any ES syntax errors or warnings in real time as you code.
Previously you had to install a third-party package called “Web Analyzer”, but as of this Tooling Preview release if you install Web Analyzer, it will instruct you to uninstall it and install the official Tooling Preview update instead.