Implement signatureHelp and implementation

examples/server.rs

@@ -1,5 +1,6 @@
 use futures::future;
 use jsonrpc_core::{BoxFuture, Result};
+use lsp_types::request::GotoImplementationResponse;
 use serde_json::Value;
 use tower_lsp::lsp_types::request::GotoDefinitionResponse;
 use tower_lsp::lsp_types::*;
@@ -18,6 +19,8 @@ impl LanguageServer for Backend {
     type DefinitionFuture = BoxFuture<Option<GotoDefinitionResponse>>;
     type TypeDefinitionFuture = BoxFuture<Option<GotoDefinitionResponse>>;
     type HighlightFuture = BoxFuture<Option<Vec<DocumentHighlight>>>;
+    type SignatureHelpFuture = BoxFuture<Option<SignatureHelp>>;
+    type GotoImplementationFuture = BoxFuture<Option<GotoImplementationResponse>>;
 
     fn initialize(&self, _: &Printer, _: InitializeParams) -> Result<InitializeResult> {
         Ok(InitializeResult {
@@ -125,6 +128,14 @@ impl LanguageServer for Backend {
     fn document_highlight(&self, _: TextDocumentPositionParams) -> Self::HighlightFuture {
         Box::new(future::ok(None))
     }
+
+    fn signature_help(&self, _: TextDocumentPositionParams) -> Self::SignatureHelpFuture {
+        Box::new(future::ok(None))
+    }
+
+    fn goto_implementation(&self, _: TextDocumentPositionParams) -> Self::GotoImplementationFuture {
+        Box::new(future::ok(None))
+    }
 }
 
 fn main() {

src/delegate.rs

@@ -98,6 +98,12 @@ pub trait LanguageServerCore {
 
     #[rpc(name = "textDocument/documentHighlight", raw_params)]
     fn document_highlight(&self, params: Params) -> BoxFuture<Option<Vec<DocumentHighlight>>>;
+
+    #[rpc(name = "textDocument/signatureHelp", raw_params)]
+    fn signature_help(&self, params: Params) -> BoxFuture<Option<SignatureHelp>>;
+
+    #[rpc(name = "textDocument/implementation", raw_params)]
+    fn goto_implementation(&self, params: Params) -> BoxFuture<Option<GotoImplementationResponse>>;
 }
 
 /// Wraps the language server backend and provides a `Printer` for sending notifications.
@@ -270,6 +276,18 @@ impl<T: LanguageServer> LanguageServerCore for Delegate<T> {
             Box::new(self.server.document_highlight(p))
         })
     }
+
+    fn signature_help(&self, params: Params) -> BoxFuture<Option<SignatureHelp>> {
+        self.delegate_request::<SignatureHelpRequest, _>(params, |p| {
+            Box::new(self.server.signature_help(p))
+        })
+    }
+
+    fn goto_implementation(&self, params: Params) -> BoxFuture<Option<GotoImplementationResponse>> {
+        self.delegate_request::<GotoImplementation, _>(params, |p| {
+            Box::new(self.server.goto_implementation(p))
+        })
+    }
 }
 
 /// Error response returned for every request received before the server is initialized.

src/lib.rs

@@ -8,7 +8,7 @@
 //! # use futures::future;
 //! # use jsonrpc_core::{BoxFuture, Result};
 //! # use serde_json::Value;
-//! # use tower_lsp::lsp_types::request::GotoDefinitionResponse;
+//! # use tower_lsp::lsp_types::request::{GotoDefinitionResponse, GotoImplementationResponse};
 //! # use tower_lsp::lsp_types::*;
 //! # use tower_lsp::{LanguageServer, LspService, Printer, Server};
 //! #
@@ -25,6 +25,9 @@
 //!     type DefinitionFuture = BoxFuture<Option<GotoDefinitionResponse>>;
 //!     type TypeDefinitionFuture = BoxFuture<Option<GotoDefinitionResponse>>;
 //!     type HighlightFuture = BoxFuture<Option<Vec<DocumentHighlight>>>;
+//!     type SignatureHelpFuture = BoxFuture<Option<SignatureHelp>>;
+//!     type GotoImplementationFuture = BoxFuture<Option<GotoImplementationResponse>>;
+//!
 //!
 //!     fn initialize(&self, _: &Printer, _: InitializeParams) -> Result<InitializeResult> {
 //!         Ok(InitializeResult::default())
@@ -69,6 +72,14 @@
 //!     fn document_highlight(&self, _: TextDocumentPositionParams) -> Self::HighlightFuture {
 //!         Box::new(future::ok(None))
 //!     }
+//!
+//!     fn signature_help(&self,params: TextDocumentPositionParams) -> Self::SignatureHelpFuture {
+//!         Box::new(future::ok(None))
+//!     }
+//!
+//!     fn goto_implementation(&self,params: TextDocumentPositionParams) -> Self::GotoImplementationFuture {
+//!         Box::new(future::ok(None))
+//!     }
 //! }
 //!
 //! fn main() {
@@ -98,7 +109,7 @@ pub use self::stdio::Server;
 
 use futures::Future;
 use jsonrpc_core::{Error, Result};
-use lsp_types::request::GotoDefinitionResponse;
+use lsp_types::request::{GotoDefinitionResponse, GotoImplementationResponse};
 use lsp_types::*;
 use serde_json::Value;
 
@@ -133,6 +144,11 @@ pub trait LanguageServer: Send + Sync + 'static {
     type TypeDefinitionFuture: Future<Item = Option<GotoDefinitionResponse>, Error = Error> + Send;
     /// Response returned when a document highlight action is requested.
     type HighlightFuture: Future<Item = Option<Vec<DocumentHighlight>>, Error = Error> + Send;
+    /// Response returned when a signature help action is requested.
+    type SignatureHelpFuture: Future<Item = Option<SignatureHelp>, Error = Error> + Send;
+    /// Response returned when a goto implementation action is requested.
+    type GotoImplementationFuture: Future<Item = Option<GotoImplementationResponse>, Error = Error>
+        + Send;
 
     /// The [`initialize`] request is the first request sent from the client to the server.
     ///
@@ -290,7 +306,7 @@ pub trait LanguageServer: Send + Sync + 'static {
     /// field to `true` in the [`initialize`] method:
     ///
     /// ```text
-    /// InitializeParams::capabilities::text_document::definition::link_support
+    /// InitializeParams::capabilities::text_document::declaration::link_support
     /// ```
     ///
     /// [`textDocument/declaration`]: https://microsoft.github.io/language-server-protocol/specifications/specification-3-15/#textDocument_declaration
@@ -322,7 +338,7 @@ pub trait LanguageServer: Send + Sync + 'static {
     /// field to `true` in the [`initialize`] method:
     ///
     /// ```text
-    /// InitializeParams::capabilities::text_document::definition::link_support
+    /// InitializeParams::capabilities::text_document::type_definition::link_support
     /// ```
     ///
     /// [`textDocument/typeDefinition`]: https://microsoft.github.io/language-server-protocol/specifications/specification-3-15/#textDocument_typeDefinition
@@ -344,6 +360,31 @@ pub trait LanguageServer: Send + Sync + 'static {
     ///
     /// [`textDocument/documentHighlight`]: https://microsoft.github.io/language-server-protocol/specifications/specification-3-15/#textDocument_documentHighlight
     fn document_highlight(&self, params: TextDocumentPositionParams) -> Self::HighlightFuture;
+
+    /// The [`textDocument/signatureHelp`] request is sent from the client to the server to request
+    /// signature information at a given cursor position.
+    ///
+    /// [`textDocument/signatureHelp`]: https://microsoft.github.io/language-server-protocol/specifications/specification-3-15/#textDocument_signatureHelp
+    fn signature_help(&self, params: TextDocumentPositionParams) -> Self::SignatureHelpFuture;
+
+    /// The [`textDocument/implementation`] request is sent from the client to the server to resolve
+    /// the implementation location of a symbol at a given text document position.
+    ///
+    /// The result type [`GotoImplementationResponse::Link`] got introduced with version 3.14.0 and
+    /// requires client-side support. It can be returned if the client set the following
+    /// field to `true` in the [`initialize`] method:
+    ///
+    /// ```text
+    /// InitializeParams::capabilities::text_document::implementation::link_support
+    /// ```
+    ///
+    /// [`textDocument/implementation`]: https://microsoft.github.io/language-server-protocol/specifications/specification-3-15/#textDocument_implementation
+    /// [`GotoImplementationResponse::Link`]: https://docs.rs/lsp-types/0.63.1/lsp_types/request/enum.GotoDefinitionResponse.html
+    /// [`initialize`]: #tymethod.initialize
+    fn goto_implementation(
+        &self,
+        params: TextDocumentPositionParams,
+    ) -> Self::GotoImplementationFuture;
 }
 
 impl<S: ?Sized + LanguageServer> LanguageServer for Box<S> {
@@ -356,6 +397,8 @@ impl<S: ?Sized + LanguageServer> LanguageServer for Box<S> {
     type DefinitionFuture = S::DefinitionFuture;
     type TypeDefinitionFuture = S::TypeDefinitionFuture;
     type HighlightFuture = S::HighlightFuture;
+    type SignatureHelpFuture = S::SignatureHelpFuture;
+    type GotoImplementationFuture = S::GotoImplementationFuture;
 
     fn initialize(&self, printer: &Printer, params: InitializeParams) -> Result<InitializeResult> {
         (**self).initialize(printer, params)
@@ -389,10 +432,6 @@ impl<S: ?Sized + LanguageServer> LanguageServer for Box<S> {
         (**self).execute_command(p, params)
     }
 
-    fn completion(&self, params: CompletionParams) -> Self::CompletionFuture {
-        (**self).completion(params)
-    }
-
     fn did_open(&self, printer: &Printer, params: DidOpenTextDocumentParams) {
         (**self).did_open(printer, params);
     }
@@ -409,6 +448,10 @@ impl<S: ?Sized + LanguageServer> LanguageServer for Box<S> {
         (**self).did_close(printer, params);
     }
 
+    fn completion(&self, params: CompletionParams) -> Self::CompletionFuture {
+        (**self).completion(params)
+    }
+
     fn hover(&self, params: TextDocumentPositionParams) -> Self::HoverFuture {
         (**self).hover(params)
     }
@@ -431,4 +474,15 @@ impl<S: ?Sized + LanguageServer> LanguageServer for Box<S> {
     fn document_highlight(&self, params: TextDocumentPositionParams) -> Self::HighlightFuture {
         (**self).document_highlight(params)
     }
+
+    fn signature_help(&self, params: TextDocumentPositionParams) -> Self::SignatureHelpFuture {
+        (**self).signature_help(params)
+    }
+
+    fn goto_implementation(
+        &self,
+        params: TextDocumentPositionParams,
+    ) -> Self::GotoImplementationFuture {
+        (**self).goto_implementation(params)
+    }
 }

src/service.rs

@@ -172,7 +172,7 @@ impl Service<Incoming> for LspService {
 #[cfg(test)]
 mod tests {
     use jsonrpc_core::{BoxFuture, Result};
-    use lsp_types::request::GotoDefinitionResponse;
+    use lsp_types::request::{GotoDefinitionResponse, GotoImplementationResponse};
     use lsp_types::*;
     use serde_json::Value;
 
@@ -192,6 +192,8 @@ mod tests {
         type DefinitionFuture = BoxFuture<Option<GotoDefinitionResponse>>;
         type TypeDefinitionFuture = BoxFuture<Option<GotoDefinitionResponse>>;
         type HighlightFuture = BoxFuture<Option<Vec<DocumentHighlight>>>;
+        type SignatureHelpFuture = BoxFuture<Option<SignatureHelp>>;
+        type GotoImplementationFuture = BoxFuture<Option<GotoImplementationResponse>>;
 
         fn initialize(&self, _: &Printer, _: InitializeParams) -> Result<InitializeResult> {
             Ok(InitializeResult::default())
@@ -235,6 +237,17 @@ mod tests {
         fn document_highlight(&self, _: TextDocumentPositionParams) -> Self::HighlightFuture {
             Box::new(future::ok(None))
         }
+
+        fn signature_help(&self, _: TextDocumentPositionParams) -> Self::SignatureHelpFuture {
+            Box::new(future::ok(None))
+        }
+
+        fn goto_implementation(
+            &self,
+            _: TextDocumentPositionParams,
+        ) -> Self::GotoImplementationFuture {
+            Box::new(future::ok(None))
+        }
     }
 
     #[test]