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. For example:

  • Ethereum style address literals like 0xE0f5206BBD039e7b0592d8918820024e2a7437b9 are not supported on Substrate or Solana, but are supported for EVM.

  • On Substrate and Solana, base58 style encoded address literals like address"5GBWmgdFAMqm8ZgAHGobqDqX6tjLxJhv53ygjNtaaAn3sjeZ" are supported, but not with EVM.

  • On Solana, there is special builtin import file called 'solana' available.

  • Different blockchains offer different builtins. See the builtins documentation.

  • See Brief Language status for compatiblity with Ethereum Solidity (solc)

  • There are many more differences, which are noted throughout the documentation.

You can choose the between the following targets:

solana

Solidity for Solana

substrate

Solidity for Substrate (Polkadot)

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 (yet).

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-0.3.0.vsix which can be installed using code --install-extension solang-0.3.0.vsix.

Alternatively, the extension be 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.