Visual Studio Code Extension

Solang has a language server built into the executable, which can be used by the Visual Studio Code extension, or by any editor that can use a lsp language server. The Visual Studio Code extension provides the following:

  1. Syntax highlighting.

  2. Compiler warnings and errors displayed in the problems tab and marked with squiggly lines.

  3. Additional information when hovering over variables, types, functions, etc. For example, this will give the struct fields when hovering over a variable which is a reference to a struct.

_images/extension-screenshot.png

Both the Visual Studio Code extension code and the language server were developed under a Hyperledger Mentorship programme.

Solidity Language flavour

The Solidity language flavour depends on what target you are compiling for, see Brief Language status for a brief overview.

You can choose between the following targets:

solana

Solidity for Solana

polkadot

Solidity for Polkadot (Substrate contracts pallet)

evm

Solidity for any EVM based chain like Ethereum

Note that the language server has support for EVM, but Hyperledger Solang does not support compiling for EVM.

Using the extension

The extension can be found on the Visual Studio Marketplace.

When started for the first time, the extension will download the Solang binary. Once this is done, it should just automatically work. Updates are downloaded when made available. However, you should set the blockchain target in the extension settings.

_images/extension-config.png

Development

The code is spread over two parts. The first part the vscode extension client code, written in TypeScript. This part deals with syntax highlighting, and calling out to the Solang language server when needed. The client needs npm and node installed. The client implementation is present in src/client. The extension client code is in src/client/extension.ts.

Secondly, there is the language server which is written in Rust. The Solang binary has a subcommand language-server, which starts the built-in language server.

Once you have node and npm installed, you can build the extension like so:

git clone https://github.com/hyperledger/solang
cd solang/vscode
npm install
npm install -g vsce
vsce package

You should now have an extension file called solang-0.3.3.vsix which can be installed using code --install-extension solang-0.3.3.vsix.

Alternatively, the extension is run from vscode itself.

  1. Inside a vscode instance, Ctrl+Shift+B to build the project

  2. On the task bar at the bottom of the IDE select Launch Client

  3. Open a Solidity file (.sol) to test the extension.

To run the tests:

  1. Inside a vscode instance, Ctrl+Shift+B to build the project

  2. On the task bar at the bottom of the IDE select Extensions tests

  3. The result should be displayed in the debug console of the host IDE instance.