feat(nargo): Add lsp command to start server that reports no capabilities

Cargo.toml

@@ -30,23 +30,27 @@ fm = { path = "crates/fm" }
 iter-extended = { path = "crates/iter-extended" }
 nargo = { path = "crates/nargo" }
 nargo_cli = { path = "crates/nargo_cli" }
+nargo_lsp = { path = "crates/nargo_lsp" }
 noirc_abi = { path = "crates/noirc_abi" }
 noirc_driver = { path = "crates/noirc_driver" }
 noirc_errors = { path = "crates/noirc_errors" }
 noirc_evaluator = { path = "crates/noirc_evaluator" }
 noirc_frontend = { path = "crates/noirc_frontend" }
 noir_wasm = { path = "crates/wasm" }
 
+async-lsp = { version = "0.0.4", default-features = false, features = ["omni-trait"] }
 cfg-if = "1.0.0"
 clap = { version = "4.1.4", features = ["derive"]}
 codespan = "0.9.5"
 codespan-reporting = "0.9.5"
 chumsky = { git = "https://github.com/jfecher/chumsky", rev = "ad9d312" }
 dirs = "4"
 serde = { version = "1.0.136", features = ["derive"] }
+serde_json = "1.0"
 smol_str = "0.1.17"
 thiserror = "1.0.21"
 toml = "0.7.2"
+tower = "0.4"
 url = "2.2.0"
 wasm-bindgen = { version = "0.2.83", features = ["serde-serialize"] }
 wasm-bindgen-test = "0.3.33"

crates/nargo_cli/Cargo.toml

@@ -18,22 +18,25 @@ build-data = "0.1.3"
 toml.workspace = true
 
 [dependencies]
+async-lsp.workspace = true
 cfg-if.workspace = true
 clap.workspace = true
 dirs.workspace = true
 url.workspace = true
 iter-extended.workspace = true
 nargo.workspace = true
+nargo_lsp.workspace = true
 noirc_driver.workspace = true
 noirc_frontend.workspace = true
 noirc_abi.workspace = true
 acvm.workspace = true
 toml.workspace = true
 serde.workspace = true
+serde_json.workspace = true
 thiserror.workspace = true
+tower.workspace = true
 const_format = "0.2.30"
 hex = "0.4.2"
-serde_json = "1.0"
 termcolor = "1.1.2"
 color-eyre = "0.6.2"
 tokio = "1.0"
@@ -50,5 +53,15 @@ predicates = "2.1.5"
 [features]
 default = ["plonk_bn254"]
 # The plonk backend can only use bn254, so we do not specify the field
-plonk_bn254 = ["acvm-backend-barretenberg/native"]
-plonk_bn254_wasm = ["acvm-backend-barretenberg/wasm"]
+plonk_bn254 = [
+    "acvm-backend-barretenberg/native",
+    "async-lsp/client-monitor",
+    "async-lsp/stdio",
+    "async-lsp/tracing"
+]
+plonk_bn254_wasm = [
+    "acvm-backend-barretenberg/wasm",
+    "async-lsp/client-monitor",
+    "async-lsp/stdio",
+    "async-lsp/tracing"
+]

crates/nargo_cli/src/cli/lsp_cmd.rs

@@ -0,0 +1,48 @@
+use acvm::Backend;
+use async_lsp::{
+    client_monitor::ClientProcessMonitorLayer, concurrency::ConcurrencyLayer,
+    panic::CatchUnwindLayer, server::LifecycleLayer, stdio::PipeStdin, tracing::TracingLayer,
+};
+use clap::Args;
+use nargo_lsp::NargoLspService;
+use noirc_driver::CompileOptions;
+use tokio::io::BufReader;
+use tower::ServiceBuilder;
+
+use super::NargoConfig;
+use crate::errors::CliError;
+
+#[derive(Debug, Clone, Args)]
+pub(crate) struct LspCommand {
+    #[clap(flatten)]
+    compile_options: CompileOptions,
+}
+
+pub(crate) fn run<B: Backend>(
+    // Backend is currently unused, but we might want to use it to inform the lsp in the future
+    _backend: &B,
+    _args: LspCommand,
+    _config: NargoConfig,
+) -> Result<(), CliError<B>> {
+    use tokio::runtime::Builder;
+
+    let runtime = Builder::new_current_thread().enable_all().build().unwrap();
+
+    let (server, _) = async_lsp::Frontend::new_server(|client| {
+        let router = NargoLspService::new();
+
+        ServiceBuilder::new()
+            .layer(TracingLayer::default())
+            .layer(LifecycleLayer::default())
+            .layer(CatchUnwindLayer::default())
+            .layer(ConcurrencyLayer::default())
+            .layer(ClientProcessMonitorLayer::new(client))
+            .service(router)
+    });
+
+    runtime.block_on(async {
+        let stdin = BufReader::new(PipeStdin::lock().unwrap());
+        let stdout = async_lsp::stdio::PipeStdout::lock().unwrap();
+        server.run(stdin, stdout).await.map_err(CliError::LspError)
+    })
+}

crates/nargo_cli/src/cli/mod.rs

@@ -14,6 +14,7 @@ mod codegen_verifier_cmd;
 mod compile_cmd;
 mod execute_cmd;
 mod gates_cmd;
+mod lsp_cmd;
 mod new_cmd;
 mod prove_cmd;
 mod test_cmd;
@@ -55,13 +56,14 @@ enum NargoCommand {
     Verify(verify_cmd::VerifyCommand),
     Test(test_cmd::TestCommand),
     Gates(gates_cmd::GatesCommand),
+    Lsp(lsp_cmd::LspCommand),
 }
 
 pub fn start_cli() -> eyre::Result<()> {
     let NargoCli { command, mut config } = NargoCli::parse();
 
     // Search through parent directories to find package root if necessary.
-    if !matches!(command, NargoCommand::New(_)) {
+    if !matches!(command, NargoCommand::New(_)) && !matches!(command, NargoCommand::Lsp(_)) {
         config.program_dir = find_package_root(&config.program_dir)?;
     }
 
@@ -77,6 +79,7 @@ pub fn start_cli() -> eyre::Result<()> {
         NargoCommand::Test(args) => test_cmd::run(&backend, args, config),
         NargoCommand::Gates(args) => gates_cmd::run(&backend, args, config),
         NargoCommand::CodegenVerifier(args) => codegen_verifier_cmd::run(&backend, args, config),
+        NargoCommand::Lsp(args) => lsp_cmd::run(&backend, args, config),
     }?;
 
     Ok(())

crates/nargo_cli/src/errors.rs

@@ -55,6 +55,9 @@ pub(crate) enum CliError<B: Backend> {
     #[error(transparent)]
     FilesystemError(#[from] FilesystemError),
 
+    #[error(transparent)]
+    LspError(#[from] async_lsp::Error),
+
     /// Error from Nargo
     #[error(transparent)]
     NargoError(#[from] NargoError),