propagate snippet support status from client capabilities

Author: zth

server/src/server.ts

@@ -46,6 +46,7 @@ interface extensionConfiguration {
 // work in one client, like VSCode, but perhaps not in others, like vim.
 export interface extensionClientCapabilities {
   supportsMarkdownLinks?: boolean | null;
+  supportsSnippetSyntax?: boolean | null;
 }
 let extensionClientCapabilities: extensionClientCapabilities = {};
 
@@ -680,7 +681,7 @@ function completion(msg: p.RequestMessage) {
       params.position.line,
       params.position.character,
       tmpname,
-      "true",
+      Boolean(extensionClientCapabilities.supportsSnippetSyntax),
     ],
     msg
   );
@@ -947,7 +948,7 @@ function createInterface(msg: p.RequestMessage): p.Message {
       jsonrpc: c.jsonrpcVersion,
       id: msg.id,
       result: {
-        uri: utils.pathToURI(resiPath)
+        uri: utils.pathToURI(resiPath),
       },
     };
     return response;
@@ -1014,7 +1015,7 @@ function openCompiledFile(msg: p.RequestMessage): p.Message {
     id: msg.id,
     result: {
       uri: utils.pathToURI(compiledFilePath.result),
-    }
+    },
   };
 
   return response;
@@ -1096,6 +1097,11 @@ function onMessage(msg: p.Message) {
         extensionClientCapabilities = extensionClientCapabilitiesFromClient;
       }
 
+      extensionClientCapabilities.supportsSnippetSyntax = Boolean(
+        initParams.capabilities.textDocument?.completion?.completionItem
+          ?.snippetSupport
+      );
+
       // send the list of features we support
       let result: p.InitializeResult = {
         // This tells the client: "hey, we support the following operations".
@@ -1112,7 +1118,9 @@ function onMessage(msg: p.Message) {
           codeActionProvider: true,
           renameProvider: { prepareProvider: true },
           documentSymbolProvider: true,
-          completionProvider: { triggerCharacters: [".", ">", "@", "~", '"', "="] },
+          completionProvider: {
+            triggerCharacters: [".", ">", "@", "~", '"', "="],
+          },
           semanticTokensProvider: {
             legend: {
               tokenTypes: [