This document explains the developer workflow for making changes to the Metals extension for Visual Studio Code.
Make sure you have the following applications installed on your machine:
git
for cloning this repositoryyarn
for building a local version of the extension- Visual Studio Code (
code
from the console)
First, clone the repo and install the project dependencies.
git clone https://github.com/scalameta/metals-vscode.git
cd packages/metals-languageclient
yarn install && yarn build
cd ../metals-vscode
yarn install
code .
Next, open the file extension.ts
and make changes to the code. To try out your
change, start the plugin in debugging mode via Run > Start debugging
or by
pressing F5
. This starts a new "Extension Development Host" application with
the local Metals extension installed. Open a directory with an sbt build and
edit a *.scala
source file to start the Metals server.
It's OK if you already have installed the Metals extension from the Marketplace, the local extension overrides your existing installation only for the "Extension Development Host" application. When you quit the development host, the Metals extension from Marketplace remains installed in your regular VS Code application.
When you make further changes to the extension, quit the "Extension Development
Host" and run F5
(or Run > Start debugging
) again.
To ensure that everything is working as expected after changes it's best to
publish a vsix artifact locally. You can do this by yarn build
which will result in
the metals-.vsix being built and placed in the root of your directory.
You can then simply code <path-to-vsix-file>
which will install the extension.
You can install the extension by going to the extension menu in Visual Studio
Code and under "More Actions..." choose to "Install from VSIX...". Then open a
*.scala
file to ensure that Metals starts and works correctly.
# run unit all tests
$ yarn run test
# run unit tests that matched with the given regex
# e.g. `yarn run test -g needCheckForUpdates`
$ yarn run test -g <test name regex>
# run integration tests
$ yarn run test-extension
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