Hi, this is Pine from VS Code team. I'm working on expanding our HTML Language Server to better support WebComponents. I'd like to get some feedback from the WebComponents commitee / community on implementing WC editor support.

I also work on Vue Language Server where I'm already shipping such support for Vue-based frameworks.

Current Status

https://github.com/octref/web-components-examples

• User includes web-components.json and web-component-attributes.json in a project
• User points to these JSON files with html.experimental.custom.tags and html.experimental.custom.attributes configurations
• VS Code gets HTML completion and hover for the custom tags / attributes.

Some Background

• The TypeScript community has adopted Type Definition Files, which drives the completions, hover messages and many other language features in VS Code and other editors through javascript-typescript-langserver.
• Through Language Server Protocol, HTML Language Server in VS Code can be used in other editors too.

Use Cases

The main two use cases are:

• Someone ships my-wc-libs library. He includes web-components.json in his NPM distribution (similar to packages include d.ts files for TypeScript) and puts webComponents: "./web-components.json in his package.json. VS Code finds the JSON files to enhance its HTML support.
• Someone just wrote my-component.js locally in a project. It would be awesome if an Analyzer (non-existent yet) would figure out the customElements.define calls, generate such JSON files and feed them to the HTML Language Server to enhance its functionalities. When the user navigates to a HTML file, he should get HTML completions for the WebComponent he just defined.

Discussions

I'd like to get some input for questions below. But if you have other questions / concerns, feel welcome to chime in.

• What are some additional editor features that could be implemented for Web Components? For example, jump to definition on <my-component> in HTML goes to the JS source where the component is defined?
• Would the WebComponents committee be interested in specifying a format for such JSON files?
• Would WebComponents implement an Analyzer, similar to Polymer Analyzer for generating such JSON files on-the-fly?