Store client capability snippetSupport into config

Rename filterAndSortCompletionResponse to completion.filterAndSort
Rename index.builtin_types to index.buitinTypes

src/clang_complete.cc

@@ -447,8 +447,9 @@ void CompletionQueryMain(ClangCompleteManager* completion_manager) {
                 ls_completion_item.detail, ls_completion_item.insertText,
                 ls_completion_item.insertTextFormat,
                 &ls_completion_item.parameters_,
-                completion_manager->config_->enableSnippetInsertion);
+                completion_manager->config_->client.snippetSupport);
-            if (ls_completion_item.insertTextFormat ==
+            if (completion_manager->config_->client.snippetSupport &&
+                ls_completion_item.insertTextFormat ==
                 lsInsertTextFormat::Snippet) {
               ls_completion_item.insertText += "$0";
             }

src/config.h

@@ -87,18 +87,23 @@ struct Config {
   // inform users their vscode client is too old and needs to be updated.
   optional<int> clientVersion;
 
-  // If true parameter declarations are included in code completion when calling
-  // a function or method
-  bool enableSnippetInsertion = true;
-
   // TODO Deprecated in favor of index.comments
   int enableComments = 0;
 
-  // If true, filter and sort completion response.
+  struct ClientCapability {
-  bool filterAndSortCompletionResponse = true;
+    // TextDocumentClientCapabilities.completion.completionItem.snippetSupport
+    bool snippetSupport = false;
+  };
+  ClientCapability client;
+
+  struct Completion {
+    // If true, filter and sort completion response.
+    bool filterAndSort = true;
+  };
+  Completion completion;
 
   struct Index {
-    bool builtin_types = false;
+    bool builtinTypes = false;
 
     // 0: no; 1: Doxygen comment markers; 2: -fparse-all-comments, which includes
     // plain // /*
@@ -111,7 +116,9 @@ struct Config {
   // Dump AST after parsing if some pattern matches the source filename.
   std::vector<std::string> dumpAST;
 };
-MAKE_REFLECT_STRUCT(Config::Index, builtin_types, comments);
+MAKE_REFLECT_STRUCT(Config::ClientCapability, snippetSupport);
+MAKE_REFLECT_STRUCT(Config::Completion, filterAndSort);
+MAKE_REFLECT_STRUCT(Config::Index, builtinTypes, comments);
 MAKE_REFLECT_STRUCT(Config,
                     compilationDatabaseDirectory,
                     cacheDirectory,
@@ -146,14 +153,13 @@ MAKE_REFLECT_STRUCT(Config,
                     codeLensOnLocalVariables,
 
                     clientVersion,
-                    enableSnippetInsertion,
 
                     enableComments,
 
+                    client,
+                    completion,
                     index,
 
-                    filterAndSortCompletionResponse,
-
                     dumpAST);
 
 // Expected client version. We show an error if this doesn't match.

src/messages/initialize.cc

@@ -75,12 +75,20 @@ struct InitializeHandler : BaseMessageHandler<Ipc_InitializeRequest> {
           }
         }
       }
-      g_index_builtin_types = config->index.builtin_types;
+      g_index_builtin_types = config->index.builtinTypes;
       // TODO Remove enableComments
       if (config->index.comments > 0)
         config->enableComments = config->index.comments;
       g_enable_comments = config->enableComments;
 
+      // Client capabilities
+      if (request->params.capabilities.textDocument) {
+        const auto& cap = *request->params.capabilities.textDocument;
+        if (cap.completion && cap.completion->completionItem)
+          config->client.snippetSupport =
+              cap.completion->completionItem->snippetSupport.value_or(false);
+      }
+
       // Check client version.
       if (config->clientVersion.has_value() &&
           *config->clientVersion != kExpectedClientVersion) {

src/messages/text_document_completion.cc

@@ -309,7 +309,7 @@ struct TextDocumentCompletionHandler : MessageHandler {
 
       TrimInPlace(buffer_line);
       FilterAndSortCompletionResponse(&out, buffer_line,
-                                      config->filterAndSortCompletionResponse);
+                                      config->completion.filterAndSort);
       QueueManager::WriteStdout(IpcId::TextDocumentCompletion, out);
     } else {
       // If existing completion is empty, dont return clang-based completion
@@ -337,7 +337,7 @@ struct TextDocumentCompletionHandler : MessageHandler {
             // Emit completion results.
             FilterAndSortCompletionResponse(
                 &out, existing_completion,
-                config->filterAndSortCompletionResponse);
+                config->completion.filterAndSort);
             QueueManager::WriteStdout(IpcId::TextDocumentCompletion, out);
 
             // Cache completion results.