Catala VSCode extension and LSP server

Disclaimer

Be advised that this is a work in progress repository and is not yet considered as a fully functional VSCode extension.

Features

Client side:

• Syntax highlighting

LSP-server:

• Highlighting of miscellaneous type of errors
• Auto-completion

Getting started

Prerequisites

In order to build and use this extension, you will need to install:

• OPAM, the OCaml package manager
• npm, the JavaScript package manager

Installation

VSCode Marketplace

The simplest way to install this extension is through the VSCode marketplace which is directly accessible in VScode. However, the extension still requires the Catala LSP server which, for the time being, need to be manually installed through OPAM using this command:

opam pin catala-lsp git+https://github.com/CatalaLang/catala-language-server.git

-- and, optionally, you may also install the code formatter (see below).

Build from sources

It is also possible to build the extension from the sources through these commands:

# 1. Clone this repository
git clone https://github.com/CatalaLang/catala-language-server/
# 2. Enter the freshly created directory
cd catala-language-server/
# 3. Install the JS dependencies
npm install
# 4. Install the OCaml dependencies
opam install . --deps-only
# 5. Build the extension
npm run compile

From this point on, you may test the extension by skipping to the next section. Otherwise, you can package and install the extension in VSCode by following these extra steps:

# 1. Install VSCode extension CLI tool: e.g.,
sudo npm install -g @vscode/vsce
# 2. Package the extension
vsce package
# 3. Install the generated .vsix extension through the VSCode GUI or
#    by invoking:
code --install-extension catala-0.20.0.vsix

Testing

If you wish to test the extension without installing it, you may:

1. Open VSCode at the repository's root (e.g., in a terminal $ code .)
2. Go to "Run and Debug" in the VSCode sidebar (invoked by command "View: Show Run and Debug")
3. Choose "Launch Client" and click on the play button
4. A new VSCode window should open with the extension running
   • you can press CTRL+R to reload the extension window to apply changes

Code formatting

catala-format is an automated code formatting tool based on topiary. To install catala-format, use this command:

$ opam install catala-format

N.b. the installation may be lengthy as it needs to install topiary.

Once this is done, you may start (or reload) the extension and use the format document command: Ctrl-p and type 'Format Document'. You may also bind it to a handy keyboard shortcut. Beware: if the catala program you are trying to format cannot be properly parsed, the formatter call will fail.

catala-format can also be used as a standalone tool or plugged in your favorite IDE. Type catala-format --help in a terminal for more details.

Using the Custom Test Case Editor

The custom (visual) test case editor usage is controlled by a configuration setting. To enable or disable the custom editor:

1. Open VSCode Settings (File > Preferences > Settings)
2. Search for "Catala"
3. Find the "Catala: Enable Custom Test Case Editor" setting
4. Check or uncheck the box to enable or disable the custom test case editor
5. Reload the VSCode window for the changes to take effect (you can do this by closing and reopening VSCode, or by running the "Developer: Reload Window" command from the Command Palette)

When the custom editor is disabled, test files will open in the default text editor.

Note: After changing the setting, you must reload the VSCode window for the changes to take effect. This is because the custom editor registration happens when the extension is activated, and changing the setting doesn't automatically re-register or unregister the editor.

Developing

When developing on the "front" (typescript side) of the extension, you may invoke npm run watch to continuously build the extension.

License

All the code contained in this repository is released under the Apache license (version 2) unless another license is explicited for a sub-directory.