Developing Language Server Features

Foreword

When issue is complex, comment on feature requests first to get feedback and implementation pointers before sending PR.

Some helpful resources:

• https://code.visualstudio.com/api/language-extensions/overview
• https://code.visualstudio.com/api/language-extensions/programmatic-language-features
• https://microsoft.github.io/language-server-protocol/

Development

Vetur consists of 2 parts

• Language Client as a normal VS Code extension
• vls, the Vue Language Server

The language client launches vls on port 6005 whenever a Vue file is opened.

To compile:

yarn
yarn compile
# or yarn watch

To debug:

• The extension has a compound debug configuration named all. Run it.
• In the newly opened window, open a Vue project such as veturpack.
• Open a Vue file — this will activate vls.

It should look like this (notice the server/client under CALL STACK):

vetur.dev.vlsPath

You can use this setting to make Vetur load a development version of vls. Some use cases:

• You fixed a bug in Vetur, but the PR is pending and won't be published anytime soon.
• You want to use TS 3.1, but Vetur bundles TS 2.8.
• You are contributing to Vetur, and would run alpha/beta/RC versions in your daily development to provide feedback and find bugs.

Two ways of using it:

1. yarn global add vls and point the setting to yarn global dir + node_modules/vls
2. Clone this repo, build it and point it to the ABSOLUTE path of /server

Full error stack

git checkout v0.xx.xx
yarn && yarn compile
# https://github.com/mifi/stacktracify
npx stacktracify server/dist/vls.js.map