Implement window/showMessageRequest

autoload/LanguageClient.vim

@@ -183,6 +183,13 @@ function! s:getInput(prompt, default) abort
     return l:input
 endfunction
 
+function! s:inputlist(...) abort
+    call inputsave()
+    let l:selection = inputlist(a:000)
+    call inputrestore()
+    return l:selection
+endfunction
+
 function! s:FZF(source, sink) abort
     if !get(g:, 'loaded_fzf')
         call s:Echoerr('FZF not loaded!')

src/language_server_protocol.rs

@@ -1824,6 +1824,31 @@ impl LanguageClient {
         Ok(())
     }
 
+    pub fn window_showMessageRequest(&self, params: &Value) -> Fallible<Value> {
+        info!("Begin {}", lsp::request::ShowMessageRequest::METHOD);
+        let msg_params: ShowMessageRequestParams = params.clone().to_lsp()?;
+        let msg_actions = msg_params.actions.unwrap_or_default();
+        let actions: Vec<Value> = msg_actions
+            .into_iter()
+            .enumerate()
+            .map(|(i, item)| Value::String(format!("{}) {}", i + 1, item.title)))
+            .collect();
+        let mut options: Vec<Value> = Vec::with_capacity(actions.len() + 1);
+        options.push(Value::String(msg_params.message));
+        options.extend(actions);
+
+        let mut v = Value::Null;
+        let result: Option<i64> = self.vim()?.rpcclient.call("s:inputlist", options)?;
+        if let Some(answer) = result {
+            let raw_actions: Vec<Value> = try_get("actions", &params)?.unwrap_or_default();
+            if let Some(action) = raw_actions.get((answer - 1) as usize) {
+                v = action.clone();
+            }
+        }
+        info!("End {}", lsp::request::ShowMessageRequest::METHOD);
+        Ok(v)
+    }
+
     pub fn client_registerCapability(&self, languageId: &str, params: &Value) -> Fallible<Value> {
         info!("Begin {}", lsp::request::RegisterCapability::METHOD);
         let params: RegistrationParams = params.clone().to_lsp()?;

src/rpchandler.rs

@@ -70,6 +70,7 @@ impl LanguageClient {
             lsp::request::DocumentSymbolRequest::METHOD => {
                 self.textDocument_documentSymbol(&params)
             }
+            lsp::request::ShowMessageRequest::METHOD => self.window_showMessageRequest(&params),
             lsp::request::WorkspaceSymbol::METHOD => self.workspace_symbol(&params),
             lsp::request::CodeActionRequest::METHOD => self.textDocument_codeAction(&params),
             lsp::request::Completion::METHOD => self.textDocument_completion(&params),