wip: Fetching diagnostics, parsing notifications.

4 files changed, 301 insertions, 178 deletions

diff --git a/helix-lsp/Cargo.toml b/helix-lsp/Cargo.toml
index 1942fc24..b34c139f 100644
--- a/helix-lsp/Cargo.toml
+++ b/helix-lsp/Cargo.toml
@@ -7,6 +7,8 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+helix-core = { path = "../helix-core" }
+
 lsp-types = { version = "0.82", features = ["proposed"] }
 smol = "1.2"
 url = "2"
diff --git a/helix-lsp/log b/helix-lsp/log
new file mode 100644
index 00000000..d8370f16
--- /dev/null
+++ b/helix-lsp/log
@@ -0,0 +1,45 @@
+Sun Oct 18 21:15:33 2020:["lsp#register_server", "server registered", "typescript-language-server"]
+Sun Oct 18 21:15:33 2020:["lsp#register_server", "server registered", "elixir-ls"]
+Sun Oct 18 21:15:33 2020:["lsp#register_server", "server registered", "vue-language-server"]
+Sun Oct 18 21:15:33 2020:["lsp#register_server", "server registered", "rust-analyzer"]
+Sun Oct 18 21:15:33 2020:["s:on_text_document_did_open()", 1, "", "/Users/speed/src/helix/helix-lsp", ""]
+Sun Oct 18 21:15:34 2020:["s:on_text_document_did_close()", 1]
+Sun Oct 18 21:15:34 2020:["s:on_text_document_did_open()", 1, "rust", "/Users/speed/src/helix", "file:///Users/speed/src/helix/helix-lsp/src/lib.rs"]
+Sun Oct 18 21:15:34 2020:["Starting server", "rust-analyzer", ["rust-analyzer"]]
+Sun Oct 18 21:15:34 2020:[{"response": {"data": {"__data__": "vim-lsp", "lsp_id": 7, "server_name": "rust-analyzer"}, "message": "started lsp server successfully"}}]
+Sun Oct 18 21:15:34 2020:["--->", 7, "rust-analyzer", {"method": "initialize", "params": {"rootUri": "file:///Users/speed/src/helix/helix-lsp", "capabilities": {"workspace": {"configuration": true, "applyEdit": true}, "textDocument": {"implementation": {"linkSupport": true}, "documentSymbol": {"symbolKind": {"valueSet": [10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 1, 2, 3, 4, 5, 6, 7, 8, 9]}, "hierarchicalDocumentSymbolSupport": false}, "semanticHighlightingCapabilities": {"semanticHighlighting": false}, "codeAction": {"codeActionLiteralSupport": {"codeActionKind": {"valueSet": ["", "quickfix", "refactor", "refactor.extract", "refactor.inline", "refactor.rewrite", "source", "source.organizeImports"]}}, "dynamicRegistration": false}, "completion": {"completionItem": {"snippetSupport": false, "documentationFormat": ["plaintext"]}, "completionItemKind": {"valueSet": [10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 1, 2, 3, 4, 5, 6, 7, 8, 9]}}, "foldingRange": {"lineFoldingOnly": true}, "typeDefinition": {"linkSupport": true}, "typeHierarchy": false, "declaration": {"linkSupport": true}, "definition": {"linkSupport": true}}}, "rootPath": "/Users/speed/src/helix/helix-lsp", "processId": 22973, "trace": "off"}}]
+Sun Oct 18 21:15:34 2020:["<---", 7, "rust-analyzer", {"response": {"id": 1, "jsonrpc": "2.0", "result": {"capabilities": {"documentHighlightProvider": true, "hoverProvider": true, "typeDefinitionProvider": true, "workspaceSymbolProvider": true, "referencesProvider": true, "signatureHelpProvider": {"triggerCharacters": ["(", ","]}, "foldingRangeProvider": true, "callHierarchyProvider": true, "codeActionProvider": {"codeActionKinds": ["", "quickfix", "refactor", "refactor.extract", "refactor.inline", "refactor.rewrite"]}, "textDocumentSync": {"save": {}, "change": 2, "openClose": true}, "codeLensProvider": {"resolveProvider": true}, "implementationProvider": true, "documentOnTypeFormattingProvider": {"moreTriggerCharacter": [".", ">"], "firstTriggerCharacter": "="}, "definitionProvider": true, "selectionRangeProvider": true, "semanticTokensProvider": {"legend": {"tokenTypes": ["comment", "keyword", "string", "number", "regexp", "operator", "namespace", "type", "struct", "class", "interface", "enum", "typeParameter", "function", "member", "property", "macro", "variable", "parameter", "label", "attribute", "boolean", "builtinType", "enumMember", "escapeSequence", "formatSpecifier", "generic", "lifetime", "punctuation", "selfKeyword", "typeAlias", "union", "unresolvedReference"], "tokenModifiers": ["documentation", "declaration", "definition", "static", "abstract", "deprecated", "readonly", "constant", "controlFlow", "injected", "mutable", "unsafe", "attribute"]}, "documentProvider": true, "rangeProvider": true}, "documentFormattingProvider": true, "documentSymbolProvider": true, "experimental": {"parentModule": true, "onEnter": true, "runnables": {"kinds": ["cargo"]}, "ssr": true, "joinLines": true}, "renameProvider": {"prepareProvider": true}, "completionProvider": {"triggerCharacters": [":", "."]}}, "serverInfo": {"version": "???????", "name": "rust-analyzer"}}}, "request": {"id": 1, "jsonrpc": "2.0", "method": "initialize", "params": {"rootUri": "file:///Users/speed/src/helix/helix-lsp", "capabilities": {"workspace": {"configuration": true, "applyEdit": true}, "textDocument": {"implementation": {"linkSupport": true}, "documentSymbol": {"symbolKind": {"valueSet": [10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 1, 2, 3, 4, 5, 6, 7, 8, 9]}, "hierarchicalDocumentSymbolSupport": false}, "semanticHighlightingCapabilities": {"semanticHighlighting": false}, "codeAction": {"codeActionLiteralSupport": {"codeActionKind": {"valueSet": ["", "quickfix", "refactor", "refactor.extract", "refactor.inline", "refactor.rewrite", "source", "source.organizeImports"]}}, "dynamicRegistration": false}, "completion": {"completionItem": {"snippetSupport": false, "documentationFormat": ["plaintext"]}, "completionItemKind": {"valueSet": [10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 1, 2, 3, 4, 5, 6, 7, 8, 9]}}, "foldingRange": {"lineFoldingOnly": true}, "typeDefinition": {"linkSupport": true}, "typeHierarchy": false, "declaration": {"linkSupport": true}, "definition": {"linkSupport": true}}}, "rootPath": "/Users/speed/src/helix/helix-lsp", "processId": 22973, "trace": "off"}}}]
+Sun Oct 18 21:15:34 2020:["--->", 7, "rust-analyzer", {"method": "initialized", "params": {}}]
+Sun Oct 18 21:15:34 2020:[{"response": {"data": {"__data__": "vim-lsp", "server_name": "rust-analyzer"}, "message": "configuration sent"}}]
+Sun Oct 18 21:15:34 2020:["s:update_file_content()", 1]
+Sun Oct 18 21:15:34 2020:["--->", 7, "rust-analyzer", {"method": "textDocument/didOpen", "params": {"textDocument": {"uri": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs", "version": 1, "languageId": "rust", "text": "use std::collections::HashMap;\n\nuse jsonrpc_core as jsonrpc;\nuse lsp_types as lsp;\n\nuse serde::{Deserialize, Serialize};\nuse serde_json::Value;\n\nuse smol::channel::{Receiver, Sender};\nuse smol::io::{BufReader, BufWriter};\nuse smol::prelude::*;\nuse smol::process::{Child, ChildStderr, ChildStdin, ChildStdout, Command, Stdio};\nuse smol::Executor;\n\nuse futures_util::{select, FutureExt};\n\n/// A type representing all possible values sent from the server to the client.\n#[derive(Debug, PartialEq, Clone, Deserialize, Serialize)]\n#[serde(deny_unknown_fields)]\n#[serde(untagged)]\nenum Message {\n    /// A regular JSON-RPC request output (single response).\n    Output(jsonrpc::Output),\n    /// A notification.\n    Notification(jsonrpc::Notification),\n    /// A JSON-RPC request\n    Call(jsonrpc::Call),\n}\n\npub struct Client {\n    process: Child,\n    stderr: BufReader<ChildStderr>,\n    outgoing: Sender<Payload>,\n\n    pub request_counter: u64,\n\n    capabilities: Option<lsp::ServerCapabilities>,\n}\n\nimpl Client {\n    pub fn start(ex: &Executor, cmd: &str, args: &[String]) -> Self {\n        let mut process = Command::new(cmd)\n            .args(args)\n            .stdin(Stdio::piped())\n            .stdout(Stdio::piped())\n            .stderr(Stdio::piped())\n            .spawn()\n            .expect(\"Failed to start language server\");\n        // smol makes sure the process is reaped on drop, but using kill_on_drop(true) maybe?\n\n        // TODO: do we need bufreader/writer here? or do we use async wrappers on unblock?\n        let writer = BufWriter::new(process.stdin.take().expect(\"Failed to open stdin\"));\n        let reader = BufReader::new(process.stdout.take().expect(\"Failed to open stdout\"));\n        let stderr = BufReader::new(process.stderr.take().expect(\"Failed to open stderr\"));\n\n        let (incoming, outgoing) = Transport::start(ex, reader, writer);\n\n        Client {\n            process,\n            stderr,\n            outgoing,\n\n            request_counter: 0,\n\n            capabilities: None,\n        }\n    }\n\n    fn next_request_id(&mut self) -> jsonrpc::Id {\n        let id = jsonrpc::Id::Num(self.request_counter);\n        self.request_counter += 1;\n        id\n    }\n\n    fn to_params(value: Value) -> anyhow::Result<jsonrpc::Params> {\n        use jsonrpc::Params;\n\n        let params = match value {\n            Value::Null => Params::None,\n            Value::Bool(_) | Value::Number(_) | Value::String(_) => Params::Array(vec![value]),\n            Value::Array(vec) => Params::Array(vec),\n            Value::Object(map) => Params::Map(map),\n        };\n\n        Ok(params)\n    }\n\n    pub async fn request<R: lsp::request::Request>(\n        &mut self,\n        params: R::Params,\n    ) -> anyhow::Result<R::Result>\n    where\n        R::Params: serde::Serialize,\n        R::Result: core::fmt::Debug, // TODO: temporary\n    {\n        let params = serde_json::to_value(params)?;\n\n        let request = jsonrpc::MethodCall {\n            jsonrpc: Some(jsonrpc::Version::V2),\n            id: self.next_request_id(),\n            method: R::METHOD.to_string(),\n            params: Self::to_params(params)?,\n        };\n\n        let (tx, rx) = smol::channel::bounded::<anyhow::Result<Value>>(1);\n\n        self.outgoing\n            .send(Payload::Request {\n                chan: tx,\n                value: request,\n            })\n            .await?;\n\n        let response = rx.recv().await??;\n\n        let response = serde_json::from_value(response)?;\n\n        // TODO: we should pass request to a sender thread via a channel\n        // so it can't be interleaved\n\n        // TODO: responses can be out of order, we need to register a single shot response channel\n\n        Ok(response)\n    }\n\n    pub async fn notify<R: lsp::notification::Notification>(\n        &mut self,\n        params: R::Params,\n    ) -> anyhow::Result<()>\n    where\n        R::Params: serde::Serialize,\n    {\n        let params = serde_json::to_value(params)?;\n\n        let notification = jsonrpc::Notification {\n            jsonrpc: Some(jsonrpc::Version::V2),\n            method: R::METHOD.to_string(),\n            params: Self::to_params(params)?,\n        };\n\n        self.outgoing\n            .send(Payload::Notification(notification))\n            .await?;\n\n        Ok(())\n    }\n\n    // -------------------------------------------------------------------------------------------\n    // General messages\n    // -------------------------------------------------------------------------------------------\n\n    pub async fn initialize(&mut self) -> anyhow::Result<()> {\n        // TODO: delay any requests that are triggered prior to initialize\n\n        #[allow(deprecated)]\n        let params = lsp::InitializeParams {\n            process_id: Some(u64::from(std::process::id())),\n            root_path: None,\n            // root_uri: Some(lsp_types::Url::parse(\"file://localhost/\")?),\n            root_uri: None, // set to project root in the future\n            initialization_options: None,\n            capabilities: lsp::ClientCapabilities::default(),\n            trace: None,\n            workspace_folders: None,\n            client_info: None,\n        };\n\n        let response = self.request::<lsp::request::Initialize>(params).await?;\n        self.capabilities = Some(response.capabilities);\n\n        // next up, notify<initialized>\n        self.notify::<lsp::notification::Initialized>(lsp::InitializedParams {})\n            .await?;\n\n        Ok(())\n    }\n\n    pub async fn shutdown(&mut self) -> anyhow::Result<()> {\n        self.request::<lsp::request::Shutdown>(()).await\n    }\n\n    pub async fn exit(&mut self) -> anyhow::Result<()> {\n        self.notify::<lsp::notification::Exit>(()).await\n    }\n\n    // -------------------------------------------------------------------------------------------\n    // Text document\n    // -------------------------------------------------------------------------------------------\n\n    pub async fn text_document_did_open(\n        &mut self,\n        state: &helix_core::State,\n    ) -> anyhow::Result<()> {\n        self.notify::<lsp::notification::DidOpenTextDocument>(lsp::DidOpenTextDocumentParams {\n            text_document: lsp::TextDocumentItem {\n                uri: lsp::Url::from_file_path(\n                    std::fs::canonicalize(state.path.as_ref().unwrap()).unwrap(),\n                )\n                .unwrap(),\n                language_id: \"rust\".to_string(), // TODO: hardcoded for now\n                version: 0,\n                text: String::from(&state.doc),\n            },\n        })\n        .await\n    }\n\n    // TODO: trigger any time history.commit_revision happens\n    pub async fn text_document_did_change(\n        &mut self,\n        state: &helix_core::State,\n    ) -> anyhow::Result<()> {\n        self.notify::<lsp::notification::DidSaveTextDocument>(lsp::DidSaveTextDocumentParams {\n            text_document: lsp::TextDocumentIdentifier::new(\n                lsp::Url::from_file_path(state.path.as_ref().unwrap()).unwrap(),\n            ),\n            text: None, // TODO?\n        })\n        .await\n    }\n\n    pub async fn text_document_did_close(&mut self) -> anyhow::Result<()> {\n        unimplemented!()\n    }\n\n    // will_save / will_save_wait_until\n\n    pub async fn text_document_did_save(&mut self) -> anyhow::Result<()> {\n        unimplemented!()\n    }\n}\n\nenum Payload {\n    Request {\n        chan: Sender<anyhow::Result<Value>>,\n        value: jsonrpc::MethodCall,\n    },\n    Notification(jsonrpc::Notification),\n}\n\nstruct Transport {\n    incoming: Sender<Message>,\n    outgoing: Receiver<Payload>,\n\n    pending_requests: HashMap<jsonrpc::Id, Sender<anyhow::Result<Value>>>,\n    headers: HashMap<String, String>,\n\n    writer: BufWriter<ChildStdin>,\n    reader: BufReader<ChildStdout>,\n}\n\nimpl Transport {\n    pub fn start(\n        ex: &Executor,\n        reader: BufReader<ChildStdout>,\n        writer: BufWriter<ChildStdin>,\n    ) -> (Receiver<Message>, Sender<Payload>) {\n        let (incoming, rx) = smol::channel::unbounded();\n        let (tx, outgoing) = smol::channel::unbounded();\n\n        let transport = Self {\n            reader,\n            writer,\n            incoming,\n            outgoing,\n            pending_requests: Default::default(),\n            headers: Default::default(),\n        };\n\n        ex.spawn(transport.duplex()).detach();\n\n        (rx, tx)\n    }\n\n    async fn recv(\n        reader: &mut (impl AsyncBufRead + Unpin),\n        headers: &mut HashMap<String, String>,\n    ) -> Result<Message, std::io::Error> {\n        // read headers\n        loop {\n            let mut header = String::new();\n            // detect pipe closed if 0\n            reader.read_line(&mut header).await?;\n            let header = header.trim();\n\n            if header.is_empty() {\n                break;\n            }\n\n            let parts: Vec<&str> = header.split(\": \").collect();\n            if parts.len() != 2 {\n                // return Err(Error::new(ErrorKind::Other, \"Failed to parse header\"));\n                panic!()\n            }\n            headers.insert(parts[0].to_string(), parts[1].to_string());\n        }\n\n        // find content-length\n        let content_length = headers.get(\"Content-Length\").unwrap().parse().unwrap();\n\n        let mut content = vec![0; content_length];\n        reader.read_exact(&mut content).await?;\n        let msg = String::from_utf8(content).unwrap();\n\n        // read data\n\n        // try parsing as output (server response) or call (server request)\n        let output: serde_json::Result<Message> = serde_json::from_str(&msg);\n\n        Ok(output?)\n    }\n\n    pub async fn send_payload(&mut self, payload: Payload) -> anyhow::Result<()> {\n        match payload {\n            Payload::Request { chan, value } => {\n                self.pending_requests.insert(value.id.clone(), chan);\n\n                let json = serde_json::to_string(&value)?;\n                self.send(json).await\n            }\n            Payload::Notification(value) => {\n                let json = serde_json::to_string(&value)?;\n                self.send(json).await\n            }\n        }\n    }\n\n    pub async fn send(&mut self, request: String) -> anyhow::Result<()> {\n        println!(\"-> {}\", request);\n\n        // send the headers\n        self.writer\n            .write_all(format!(\"Content-Length: {}\\r\\n\\r\\n\", request.len()).as_bytes())\n            .await?;\n\n        // send the body\n        self.writer.write_all(request.as_bytes()).await?;\n\n        self.writer.flush().await?;\n\n        Ok(())\n    }\n\n    pub async fn recv_response(&mut self, output: jsonrpc::Output) -> anyhow::Result<()> {\n        match output {\n            jsonrpc::Output::Success(jsonrpc::Success { id, result, .. }) => {\n                println!(\"<- {}\", result);\n\n                let tx = self\n                    .pending_requests\n                    .remove(&id)\n                    .expect(\"pending_request with id not found!\");\n                tx.send(Ok(result)).await?;\n            }\n            jsonrpc::Output::Failure(_) => panic!(\"recv fail\"),\n            msg => unimplemented!(\"{:?}\", msg),\n        }\n        Ok(())\n    }\n\n    pub async fn duplex(mut self) {\n        loop {\n            select! {\n                // client -> server\n                msg = self.outgoing.next().fuse() => {\n                    if msg.is_none() {\n                        break;\n                    }\n                    let msg = msg.unwrap();\n\n                    self.send_payload(msg).await.unwrap();\n                }\n                // server <- client\n                msg = Self::recv(&mut self.reader, &mut self.headers).fuse() => {\n                    if msg.is_err() {\n                        break;\n                    }\n                    let msg = msg.unwrap();\n\n                    match msg {\n                        Message::Output(output) => self.recv_response(output).await.unwrap(),\n                        Message::Notification(_) => {\n                            // dispatch\n                        }\n                        Message::Call(_) => {\n                            // dispatch\n                        }\n                    };\n                }\n            }\n        }\n    }\n}\n"}}}]
+Sun Oct 18 21:15:34 2020:[{"response": {"data": {"__data__": "vim-lsp", "server_name": "rust-analyzer"}, "message": "server already started"}}]
+Sun Oct 18 21:15:34 2020:[{"response": {"data": {"__data__": "vim-lsp", "init_result": {"id": 1, "jsonrpc": "2.0", "result": {"capabilities": {"documentHighlightProvider": true, "hoverProvider": true, "typeDefinitionProvider": true, "workspaceSymbolProvider": true, "referencesProvider": true, "signatureHelpProvider": {"triggerCharacters": ["(", ","]}, "foldingRangeProvider": true, "callHierarchyProvider": true, "codeActionProvider": {"codeActionKinds": ["", "quickfix", "refactor", "refactor.extract", "refactor.inline", "refactor.rewrite"]}, "textDocumentSync": {"save": {}, "change": 2, "openClose": true}, "codeLensProvider": {"resolveProvider": true}, "implementationProvider": true, "documentOnTypeFormattingProvider": {"moreTriggerCharacter": [".", ">"], "firstTriggerCharacter": "="}, "definitionProvider": true, "selectionRangeProvider": true, "semanticTokensProvider": {"legend": {"tokenTypes": ["comment", "keyword", "string", "number", "regexp", "operator", "namespace", "type", "struct", "class", "interface", "enum", "typeParameter", "function", "member", "property", "macro", "variable", "parameter", "label", "attribute", "boolean", "builtinType", "enumMember", "escapeSequence", "formatSpecifier", "generic", "lifetime", "punctuation", "selfKeyword", "typeAlias", "union", "unresolvedReference"], "tokenModifiers": ["documentation", "declaration", "definition", "static", "abstract", "deprecated", "readonly", "constant", "controlFlow", "injected", "mutable", "unsafe", "attribute"]}, "documentProvider": true, "rangeProvider": true}, "documentFormattingProvider": true, "documentSymbolProvider": true, "experimental": {"parentModule": true, "onEnter": true, "runnables": {"kinds": ["cargo"]}, "ssr": true, "joinLines": true}, "renameProvider": {"prepareProvider": true}, "completionProvider": {"triggerCharacters": [":", "."]}}, "serverInfo": {"version": "???????", "name": "rust-analyzer"}}}, "server_name": "rust-analyzer"}, "message": "lsp server already initialized"}}]
+Sun Oct 18 21:15:34 2020:[{"response": {"data": {"__data__": "vim-lsp", "server_name": "rust-analyzer"}, "message": "configuration sent"}}]
+Sun Oct 18 21:15:34 2020:[{"response": {"data": {"path": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs", "__data__": "vim-lsp", "server_name": "rust-analyzer"}, "message": "already opened"}}]
+Sun Oct 18 21:15:34 2020:[{"response": {"data": {"path": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs", "__data__": "vim-lsp", "server_name": "rust-analyzer"}, "message": "not dirty"}}]
+Sun Oct 18 21:15:34 2020:["--->", 7, "rust-analyzer", {"method": "textDocument/foldingRange", "on_notification": "---funcref---", "bufnr": 1, "params": {"textDocument": {"uri": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs"}}, "sync": 0}]
+Sun Oct 18 21:15:34 2020:[{"response": {"data": {"path": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs", "__data__": "vim-lsp", "filetype": "rust", "server_name": "rust-analyzer"}, "message": "textDocument/open sent"}}]
+Sun Oct 18 21:15:34 2020:[{"response": {"data": {"path": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs", "__data__": "vim-lsp", "server_name": "rust-analyzer"}, "message": "not dirty"}}]
+Sun Oct 18 21:15:35 2020:["<---", 7, {"id": 0, "jsonrpc": "2.0", "method": "client/registerCapability", "params": {"registrations": [{"id": "textDocument/didSave", "registerOptions": {"includeText": false, "documentSelector": [{"pattern": "**/*.rs"}, {"pattern": "**/Cargo.toml"}, {"pattern": "**/Cargo.lock"}]}, "method": "textDocument/didSave"}]}}]
+Sun Oct 18 21:15:35 2020:["--->", 7, "rust-analyzer", {"id": 0, "error": {"code": -32601, "message": "Method not found"}}]
+Sun Oct 18 21:15:35 2020:["<---", 7, "rust-analyzer", {"response": {"id": 2, "jsonrpc": "2.0", "result": [{"startLine": 2, "kind": "imports", "endLine": 3}, {"startLine": 5, "kind": "imports", "endLine": 6}, {"startLine": 8, "kind": "imports", "endLine": 12}, {"startLine": 20, "endLine": 27}, {"startLine": 29, "endLine": 37}, {"startLine": 39, "endLine": 230}, {"startLine": 40, "endLine": 66}, {"startLine": 57, "endLine": 65}, {"startLine": 68, "endLine": 72}, {"startLine": 74, "endLine": 85}, {"startLine": 77, "endLine": 81}, {"startLine": 87, "endLine": 89}, {"startLine": 94, "endLine": 123}, {"startLine": 97, "endLine": 101}, {"startLine": 107, "endLine": 110}, {"startLine": 107, "endLine": 109}, {"startLine": 117, "kind": "comment", "endLine": 118}, {"startLine": 125, "endLine": 127}, {"startLine": 131, "endLine": 145}, {"startLine": 134, "endLine": 137}, {"startLine": 147, "kind": "comment", "endLine": 149}, {"startLine": 151, "endLine": 175}, {"startLine": 155, "endLine": 164}, {"startLine": 177, "endLine": 179}, {"startLine": 181, "endLine": 183}, {"startLine": 185, "kind": "comment", "endLine": 187}, {"startLine": 189, "endLine": 191}, {"startLine": 192, "endLine": 205}, {"startLine": 193, "endLine": 203}, {"startLine": 193, "endLine": 202}, {"startLine": 194, "endLine": 201}, {"startLine": 195, "endLine": 197}, {"startLine": 208, "endLine": 210}, {"startLine": 211, "endLine": 219}, {"startLine": 212, "endLine": 217}, {"startLine": 212, "endLine": 216}, {"startLine": 213, "endLine": 214}, {"startLine": 221, "endLine": 223}, {"startLine": 227, "endLine": 229}, {"startLine": 232, "endLine": 238}, {"startLine": 233, "endLine": 235}, {"startLine": 240, "endLine": 249}, {"startLine": 251, "endLine": 392}, {"startLine": 252, "endLine": 255}, {"startLine": 256, "endLine": 272}, {"startLine": 260, "endLine": 266}, {"startLine": 274, "endLine": 276}, {"startLine": 277, "endLine": 310}, {"startLine": 279, "endLine": 295}, {"startLine": 285, "endLine": 287}, {"startLine": 290, "endLine": 293}, {"startLine": 312, "endLine": 325}, {"startLine": 313, "endLine": 324}, {"startLine": 314, "endLine": 319}, {"startLine": 320, "endLine": 323}, {"startLine": 327, "endLine": 341}, {"startLine": 343, "endLine": 358}, {"startLine": 344, "endLine": 356}, {"startLine": 345, "endLine": 353}, {"startLine": 360, "endLine": 391}, {"startLine": 361, "endLine": 390}, {"startLine": 362, "endLine": 389}, {"startLine": 364, "endLine": 371}, {"startLine": 365, "endLine": 367}, {"startLine": 373, "endLine": 388}, {"startLine": 374, "endLine": 376}, {"startLine": 379, "endLine": 386}, {"startLine": 381, "endLine": 383}, {"startLine": 384, "endLine": 386}]}, "request": {"id": 2, "jsonrpc": "2.0", "method": "textDocument/foldingRange", "params": {"textDocument": {"uri": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs"}}}}]
+Sun Oct 18 21:15:36 2020:["<---", 7, "rust-analyzer", {"response": {"method": "textDocument/publishDiagnostics", "jsonrpc": "2.0", "params": {"diagnostics": [{"source": "rustc", "range": {"end": {"character": 15, "line": 355}, "start": {"character": 12, "line": 355}}, "code": "unreachable_patterns", "message": "unreachable pattern\n`#[warn(unreachable_patterns)]` on by default", "severity": 2}], "uri": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs", "version": 1}}}]
+Sun Oct 18 21:15:36 2020:["<---", 7, "rust-analyzer", {"response": {"method": "textDocument/publishDiagnostics", "jsonrpc": "2.0", "params": {"diagnostics": [{"source": "rustc", "tags": [1], "range": {"end": {"character": 28, "line": 618}, "start": {"character": 24, "line": 618}}, "code": "unused_variables", "message": "unused variable: `view`\n`#[warn(unused_variables)]` on by default", "severity": 2}], "uri": "file:///Users/speed/src/helix/helix-view/src/commands.rs"}}}]
+Sun Oct 18 21:15:36 2020:["<---", 7, "rust-analyzer", {"response": {"method": "textDocument/publishDiagnostics", "jsonrpc": "2.0", "params": {"diagnostics": [{"source": "rustc", "range": {"end": {"character": 15, "line": 355}, "start": {"character": 12, "line": 355}}, "code": "unreachable_patterns", "message": "unreachable pattern\n`#[warn(unreachable_patterns)]` on by default", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 21, "line": 55}, "start": {"character": 13, "line": 55}}, "code": "unused_variables", "message": "unused variable: `incoming`\n`#[warn(unused_variables)]` on by default", "severity": 2}], "uri": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs", "version": 1}}}]
+Sun Oct 18 21:15:36 2020:["<---", 7, "rust-analyzer", {"response": {"method": "textDocument/publishDiagnostics", "jsonrpc": "2.0", "params": {"diagnostics": [{"source": "rustc", "range": {"end": {"character": 15, "line": 355}, "start": {"character": 12, "line": 355}}, "code": "unreachable_patterns", "message": "unreachable pattern\n`#[warn(unreachable_patterns)]` on by default", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 21, "line": 55}, "start": {"character": 13, "line": 55}}, "code": "unused_variables", "message": "unused variable: `incoming`\n`#[warn(unused_variables)]` on by default", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 18, "line": 30}, "start": {"character": 4, "line": 30}}, "code": "dead_code", "message": "field is never read: `process`\n`#[warn(dead_code)]` on by default", "severity": 2}], "uri": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs", "version": 1}}}]
+Sun Oct 18 21:15:36 2020:["<---", 7, "rust-analyzer", {"response": {"method": "textDocument/publishDiagnostics", "jsonrpc": "2.0", "params": {"diagnostics": [{"source": "rustc", "range": {"end": {"character": 15, "line": 355}, "start": {"character": 12, "line": 355}}, "code": "unreachable_patterns", "message": "unreachable pattern\n`#[warn(unreachable_patterns)]` on by default", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 21, "line": 55}, "start": {"character": 13, "line": 55}}, "code": "unused_variables", "message": "unused variable: `incoming`\n`#[warn(unused_variables)]` on by default", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 18, "line": 30}, "start": {"character": 4, "line": 30}}, "code": "dead_code", "message": "field is never read: `process`\n`#[warn(dead_code)]` on by default", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 34, "line": 31}, "start": {"character": 4, "line": 31}}, "code": "dead_code", "message": "field is never read: `stderr`", "severity": 2}], "uri": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs", "version": 1}}}]
+Sun Oct 18 21:15:36 2020:["<---", 7, "rust-analyzer", {"response": {"method": "textDocument/publishDiagnostics", "jsonrpc": "2.0", "params": {"diagnostics": [{"source": "rustc", "range": {"end": {"character": 15, "line": 355}, "start": {"character": 12, "line": 355}}, "code": "unreachable_patterns", "message": "unreachable pattern\n`#[warn(unreachable_patterns)]` on by default", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 21, "line": 55}, "start": {"character": 13, "line": 55}}, "code": "unused_variables", "message": "unused variable: `incoming`\n`#[warn(unused_variables)]` on by default", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 18, "line": 30}, "start": {"character": 4, "line": 30}}, "code": "dead_code", "message": "field is never read: `process`\n`#[warn(dead_code)]` on by default", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 34, "line": 31}, "start": {"character": 4, "line": 31}}, "code": "dead_code", "message": "field is never read: `stderr`", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 29, "line": 241}, "start": {"character": 4, "line": 241}}, "code": "dead_code", "message": "field is never read: `incoming`", "severity": 2}], "uri": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs", "version": 1}}}]
+Sun Oct 18 21:15:39 2020:["lsp#register_server", "server registered", "typescript-language-server"]
+Sun Oct 18 21:15:39 2020:["lsp#register_server", "server registered", "elixir-ls"]
+Sun Oct 18 21:15:39 2020:["lsp#register_server", "server registered", "vue-language-server"]
+Sun Oct 18 21:15:39 2020:["lsp#register_server", "server registered", "rust-analyzer"]
+Sun Oct 18 21:15:39 2020:["s:on_text_document_did_open()", 1, "vim", "/Users/speed/src/helix/helix-lsp", "file:///Users/speed/.vimrc"]
+Sun Oct 18 21:15:40 2020:["s:on_text_document_did_change()", 1]
+Sun Oct 18 21:15:40 2020:["s:send_didchange_queue() will be triggered"]
+Sun Oct 18 21:15:40 2020:["s:on_text_document_did_change()", 1]
+Sun Oct 18 21:15:41 2020:["s:on_text_document_did_save()", 1]
+Sun Oct 18 21:15:41 2020:["s:on_text_document_did_close()", 1]
+Sun Oct 18 21:15:55 2020:["<---", 7, "rust-analyzer", {"response": {"method": "textDocument/publishDiagnostics", "jsonrpc": "2.0", "params": {"diagnostics": [{"source": "rustc", "range": {"end": {"character": 15, "line": 355}, "start": {"character": 12, "line": 355}}, "code": "unreachable_patterns", "message": "unreachable pattern\n`#[warn(unreachable_patterns)]` on by default", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 21, "line": 55}, "start": {"character": 13, "line": 55}}, "code": "unused_variables", "message": "unused variable: `incoming`\n`#[warn(unused_variables)]` on by default", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 18, "line": 30}, "start": {"character": 4, "line": 30}}, "code": "dead_code", "message": "field is never read: `process`\n`#[warn(dead_code)]` on by default", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 34, "line": 31}, "start": {"character": 4, "line": 31}}, "code": "dead_code", "message": "field is never read: `stderr`", "severity": 2}, {"source": "rustc", "tags": [1], "range": {"end": {"character": 29, "line": 241}, "start": {"character": 4, "line": 241}}, "code": "dead_code", "message": "field is never read: `incoming`", "severity": 2}], "uri": "file:///Users/speed/src/helix/helix-lsp/src/lib.rs", "version": 1}}}]
+Sun Oct 18 21:15:57 2020:["s:on_text_document_did_close()", 1]
+Sun Oct 18 21:15:57 2020:["s:on_exit", 7, "rust-analyzer", "exited", 143]
diff --git a/helix-lsp/src/lib.rs b/helix-lsp/src/lib.rs
index b371f337..41b3fdb2 100644
--- a/helix-lsp/src/lib.rs
+++ b/helix-lsp/src/lib.rs
@@ -1,18 +1,22 @@
+mod transport;
+
+use transport::{Payload, Transport};
+
 use std::collections::HashMap;
 
 use jsonrpc_core as jsonrpc;
 use lsp_types as lsp;
+use serde_json::Value;
 
 use serde::{Deserialize, Serialize};
-use serde_json::Value;
 
-use smol::channel::{Receiver, Sender};
-use smol::io::{BufReader, BufWriter};
 use smol::prelude::*;
-use smol::process::{Child, ChildStderr, ChildStdin, ChildStdout, Command, Stdio};
-use smol::Executor;
-
-use futures_util::{select, FutureExt};
+use smol::{
+    channel::{Receiver, Sender},
+    io::{BufReader, BufWriter},
+    process::{Child, ChildStderr, Command, Stdio},
+    Executor,
+};
 
 /// A type representing all possible values sent from the server to the client.
 #[derive(Debug, PartialEq, Clone, Deserialize, Serialize)]
@@ -27,14 +31,40 @@ enum Message {
     Call(jsonrpc::Call),
 }
 
+#[derive(Debug, PartialEq, Clone)]
+enum Notification {}
+
+impl Notification {
+    pub fn parse(method: &str, params: jsonrpc::Params) {
+        use lsp::notification::Notification as _;
+
+        match method {
+            lsp::notification::PublishDiagnostics::METHOD => {
+                let params: lsp::PublishDiagnosticsParams = params
+                    .parse()
+                    .expect("Failed to parse PublishDiagnostics params");
+
+                println!("{:?}", params);
+
+                // TODO: need to loop over diagnostics and distinguish them by URI
+            }
+            _ => println!("unhandled notification: {}", method),
+        }
+    }
+}
+
 pub struct Client {
     process: Child,
     stderr: BufReader<ChildStderr>,
+
     outgoing: Sender<Payload>,
+    incoming: Receiver<Message>,
 
     pub request_counter: u64,
 
     capabilities: Option<lsp::ServerCapabilities>,
+    // TODO: handle PublishDiagnostics Version
+    diagnostics: HashMap<lsp::Url, Vec<lsp::Diagnostic>>,
 }
 
 impl Client {
@@ -58,11 +88,14 @@ impl Client {
         Client {
             process,
             stderr,
+
             outgoing,
+            incoming,
 
             request_counter: 0,
 
             capabilities: None,
+            diagnostics: HashMap::new(),
         }
     }
 
@@ -187,191 +220,45 @@ impl Client {
     // Text document
     // -------------------------------------------------------------------------------------------
 
-    pub async fn text_document_did_open(&mut self) -> anyhow::Result<()> {
+    pub async fn text_document_did_open(
+        &mut self,
+        state: &helix_core::State,
+    ) -> anyhow::Result<()> {
         self.notify::<lsp::notification::DidOpenTextDocument>(lsp::DidOpenTextDocumentParams {
             text_document: lsp::TextDocumentItem {
-                uri: lsp::Url::parse(".")?,
-                language_id: "rust".to_string(),
+                uri: lsp::Url::from_file_path(
+                    std::fs::canonicalize(state.path.as_ref().unwrap()).unwrap(),
+                )
+                .unwrap(),
+                language_id: "rust".to_string(), // TODO: hardcoded for now
                 version: 0,
-                text: "".to_string(),
+                text: String::from(&state.doc),
             },
         })
         .await
     }
 
-    pub async fn text_document_did_change(&mut self) -> anyhow::Result<()> {
-        unimplemented!()
-    }
-
-    // will_save / will_save_wait_until
-
-    pub async fn text_document_did_save(&mut self) -> anyhow::Result<()> {
-        unimplemented!()
+    // TODO: trigger any time history.commit_revision happens
+    pub async fn text_document_did_change(
+        &mut self,
+        state: &helix_core::State,
+    ) -> anyhow::Result<()> {
+        self.notify::<lsp::notification::DidSaveTextDocument>(lsp::DidSaveTextDocumentParams {
+            text_document: lsp::TextDocumentIdentifier::new(
+                lsp::Url::from_file_path(state.path.as_ref().unwrap()).unwrap(),
+            ),
+            text: None, // TODO?
+        })
+        .await
     }
 
     pub async fn text_document_did_close(&mut self) -> anyhow::Result<()> {
         unimplemented!()
     }
-}
-
-enum Payload {
-    Request {
-        chan: Sender<anyhow::Result<Value>>,
-        value: jsonrpc::MethodCall,
-    },
-    Notification(jsonrpc::Notification),
-}
-
-struct Transport {
-    incoming: Sender<Message>,
-    outgoing: Receiver<Payload>,
-
-    pending_requests: HashMap<jsonrpc::Id, Sender<anyhow::Result<Value>>>,
-    headers: HashMap<String, String>,
-
-    writer: BufWriter<ChildStdin>,
-    reader: BufReader<ChildStdout>,
-}
-
-impl Transport {
-    pub fn start(
-        ex: &Executor,
-        reader: BufReader<ChildStdout>,
-        writer: BufWriter<ChildStdin>,
-    ) -> (Receiver<Message>, Sender<Payload>) {
-        let (incoming, rx) = smol::channel::unbounded();
-        let (tx, outgoing) = smol::channel::unbounded();
-
-        let transport = Self {
-            reader,
-            writer,
-            incoming,
-            outgoing,
-            pending_requests: Default::default(),
-            headers: Default::default(),
-        };
-
-        ex.spawn(transport.duplex()).detach();
-
-        (rx, tx)
-    }
-
-    async fn recv(
-        reader: &mut (impl AsyncBufRead + Unpin),
-        headers: &mut HashMap<String, String>,
-    ) -> Result<Message, std::io::Error> {
-        // read headers
-        loop {
-            let mut header = String::new();
-            // detect pipe closed if 0
-            reader.read_line(&mut header).await?;
-            let header = header.trim();
-
-            if header.is_empty() {
-                break;
-            }
-
-            let parts: Vec<&str> = header.split(": ").collect();
-            if parts.len() != 2 {
-                // return Err(Error::new(ErrorKind::Other, "Failed to parse header"));
-                panic!()
-            }
-            headers.insert(parts[0].to_string(), parts[1].to_string());
-        }
-
-        // find content-length
-        let content_length = headers.get("Content-Length").unwrap().parse().unwrap();
-
-        let mut content = vec![0; content_length];
-        reader.read_exact(&mut content).await?;
-        let msg = String::from_utf8(content).unwrap();
-
-        // read data
-
-        // try parsing as output (server response) or call (server request)
-        let output: serde_json::Result<Message> = serde_json::from_str(&msg);
-
-        Ok(output?)
-    }
 
-    pub async fn send_payload(&mut self, payload: Payload) -> anyhow::Result<()> {
-        match payload {
-            Payload::Request { chan, value } => {
-                self.pending_requests.insert(value.id.clone(), chan);
-
-                let json = serde_json::to_string(&value)?;
-                self.send(json).await
-            }
-            Payload::Notification(value) => {
-                let json = serde_json::to_string(&value)?;
-                self.send(json).await
-            }
-        }
-    }
-
-    pub async fn send(&mut self, request: String) -> anyhow::Result<()> {
-        println!("-> {}", request);
-
-        // send the headers
-        self.writer
-            .write_all(format!("Content-Length: {}\r\n\r\n", request.len()).as_bytes())
-            .await?;
-
-        // send the body
-        self.writer.write_all(request.as_bytes()).await?;
-
-        self.writer.flush().await?;
-
-        Ok(())
-    }
-
-    pub async fn recv_response(&mut self, output: jsonrpc::Output) -> anyhow::Result<()> {
-        match output {
-            jsonrpc::Output::Success(jsonrpc::Success { id, result, .. }) => {
-                println!("<- {}", result);
-
-                let tx = self
-                    .pending_requests
-                    .remove(&id)
-                    .expect("pending_request with id not found!");
-                tx.send(Ok(result)).await?;
-            }
-            jsonrpc::Output::Failure(_) => panic!("recv fail"),
-            msg => unimplemented!("{:?}", msg),
-        }
-        Ok(())
-    }
+    // will_save / will_save_wait_until
 
-    pub async fn duplex(mut self) {
-        loop {
-            select! {
-                // client -> server
-                msg = self.outgoing.next().fuse() => {
-                    if msg.is_none() {
-                        break;
-                    }
-                    let msg = msg.unwrap();
-
-                    self.send_payload(msg).await.unwrap();
-                }
-                // server <- client
-                msg = Self::recv(&mut self.reader, &mut self.headers).fuse() => {
-                    if msg.is_err() {
-                        break;
-                    }
-                    let msg = msg.unwrap();
-
-                    match msg {
-                        Message::Output(output) => self.recv_response(output).await.unwrap(),
-                        Message::Notification(_) => {
-                            // dispatch
-                        }
-                        Message::Call(_) => {
-                            // dispatch
-                        }
-                    };
-                }
-            }
-        }
+    pub async fn text_document_did_save(&mut self) -> anyhow::Result<()> {
+        unimplemented!()
     }
 }
diff --git a/helix-lsp/src/transport.rs b/helix-lsp/src/transport.rs
new file mode 100644
index 00000000..c44ffa91
--- /dev/null
+++ b/helix-lsp/src/transport.rs
@@ -0,0 +1,189 @@
+use std::collections::HashMap;
+
+use crate::{Message, Notification};
+
+use jsonrpc_core as jsonrpc;
+use lsp_types as lsp;
+use serde_json::Value;
+
+use smol::prelude::*;
+
+use smol::{
+    channel::{Receiver, Sender},
+    io::{BufReader, BufWriter},
+    process::{ChildStderr, ChildStdin, ChildStdout},
+    Executor,
+};
+
+pub(crate) enum Payload {
+    Request {
+        chan: Sender<anyhow::Result<Value>>,
+        value: jsonrpc::MethodCall,
+    },
+    Notification(jsonrpc::Notification),
+}
+
+pub(crate) struct Transport {
+    incoming: Sender<Message>,
+    outgoing: Receiver<Payload>,
+
+    pending_requests: HashMap<jsonrpc::Id, Sender<anyhow::Result<Value>>>,
+    headers: HashMap<String, String>,
+
+    writer: BufWriter<ChildStdin>,
+    reader: BufReader<ChildStdout>,
+}
+
+impl Transport {
+    pub fn start(
+        ex: &Executor,
+        reader: BufReader<ChildStdout>,
+        writer: BufWriter<ChildStdin>,
+    ) -> (Receiver<Message>, Sender<Payload>) {
+        let (incoming, rx) = smol::channel::unbounded();
+        let (tx, outgoing) = smol::channel::unbounded();
+
+        let transport = Self {
+            reader,
+            writer,
+            incoming,
+            outgoing,
+            pending_requests: Default::default(),
+            headers: Default::default(),
+        };
+
+        ex.spawn(transport.duplex()).detach();
+
+        (rx, tx)
+    }
+
+    async fn recv(
+        reader: &mut (impl AsyncBufRead + Unpin),
+        headers: &mut HashMap<String, String>,
+    ) -> Result<Message, std::io::Error> {
+        // read headers
+        loop {
+            let mut header = String::new();
+            // detect pipe closed if 0
+            reader.read_line(&mut header).await?;
+            let header = header.trim();
+
+            if header.is_empty() {
+                break;
+            }
+
+            let parts: Vec<&str> = header.split(": ").collect();
+            if parts.len() != 2 {
+                // return Err(Error::new(ErrorKind::Other, "Failed to parse header"));
+                panic!()
+            }
+            headers.insert(parts[0].to_string(), parts[1].to_string());
+        }
+
+        // find content-length
+        let content_length = headers.get("Content-Length").unwrap().parse().unwrap();
+
+        let mut content = vec![0; content_length];
+        reader.read_exact(&mut content).await?;
+        let msg = String::from_utf8(content).unwrap();
+
+        // read data
+
+        // try parsing as output (server response) or call (server request)
+        let output: serde_json::Result<Message> = serde_json::from_str(&msg);
+
+        Ok(output?)
+    }
+
+    pub async fn send_payload(&mut self, payload: Payload) -> anyhow::Result<()> {
+        match payload {
+            Payload::Request { chan, value } => {
+                self.pending_requests.insert(value.id.clone(), chan);
+
+                let json = serde_json::to_string(&value)?;
+                self.send(json).await
+            }
+            Payload::Notification(value) => {
+                let json = serde_json::to_string(&value)?;
+                self.send(json).await
+            }
+        }
+    }
+
+    pub async fn send(&mut self, request: String) -> anyhow::Result<()> {
+        println!("-> {}", request);
+
+        // send the headers
+        self.writer
+            .write_all(format!("Content-Length: {}\r\n\r\n", request.len()).as_bytes())
+            .await?;
+
+        // send the body
+        self.writer.write_all(request.as_bytes()).await?;
+
+        self.writer.flush().await?;
+
+        Ok(())
+    }
+
+    pub async fn recv_msg(&mut self, msg: Message) -> anyhow::Result<()> {
+        match msg {
+            Message::Output(output) => self.recv_response(output).await?,
+            Message::Notification(jsonrpc::Notification { method, params, .. }) => {
+                let notification = Notification::parse(&method, params);
+
+                println!("<- {} {:?}", method, notification);
+                // dispatch
+            }
+            Message::Call(call) => {
+                println!("<- {:?}", call);
+                // dispatch
+            }
+            _ => unreachable!(),
+        };
+        Ok(())
+    }
+
+    pub async fn recv_response(&mut self, output: jsonrpc::Output) -> anyhow::Result<()> {
+        match output {
+            jsonrpc::Output::Success(jsonrpc::Success { id, result, .. }) => {
+                println!("<- {}", result);
+
+                let tx = self
+                    .pending_requests
+                    .remove(&id)
+                    .expect("pending_request with id not found!");
+                tx.send(Ok(result)).await?;
+            }
+            jsonrpc::Output::Failure(_) => panic!("recv fail"),
+            msg => unimplemented!("{:?}", msg),
+        }
+        Ok(())
+    }
+
+    pub async fn duplex(mut self) {
+        use futures_util::{select, FutureExt};
+        loop {
+            select! {
+                // client -> server
+                msg = self.outgoing.next().fuse() => {
+                    if msg.is_none() {
+                        break;
+                    }
+                    let msg = msg.unwrap();
+
+                    self.send_payload(msg).await.unwrap();
+                }
+                // server <- client
+                msg = Self::recv(&mut self.reader, &mut self.headers).fuse() => {
+                    if msg.is_err() {
+                        break;
+                    }
+                    let msg = msg.unwrap();
+
+                    self.recv_msg(msg).await.unwrap();
+                }
+            }
+        }
+    }
+}