From bf011fef71ad60d04cb2924fc92d04bd2d9d4354 Mon Sep 17 00:00:00 2001
From: Boris Staletic <boris.staletic@gmail.com>
Date: Mon, 19 Mar 2018 21:28:11 +0100
Subject: [PATCH] Conditionally allow reindex on didChange

---
 src/config.h                             |  6 ++++++
 src/messages/text_document_did_change.cc | 17 +++++++++++++++++
 src/messages/text_document_did_save.cc   | 23 +++++++++++++----------
 3 files changed, 36 insertions(+), 10 deletions(-)

diff --git a/src/config.h b/src/config.h
index 9ca7ab5b..9030a903 100644
--- a/src/config.h
+++ b/src/config.h
@@ -212,6 +212,10 @@ struct Config {
     bool sort = true;
   } workspaceSymbol;
 
+  // Allow indexing on textDocument/didChange.
+  // May be too slow for big projects, so it is off by default.
+  bool enableIndexOnDidChange = false;
+
   struct Xref {
     // If true, |Location[]| response will include lexical container.
     bool container = false;
@@ -272,6 +276,8 @@ MAKE_REFLECT_STRUCT(Config,
                     index,
                     workspaceSymbol,
                     xref,
+                    
+                    enableIndexOnDidChange,
 
                     dumpAST);
 
diff --git a/src/messages/text_document_did_change.cc b/src/messages/text_document_did_change.cc
index 90e6dc9c..d32f2097 100644
--- a/src/messages/text_document_did_change.cc
+++ b/src/messages/text_document_did_change.cc
@@ -1,6 +1,11 @@
+#include "cache_manager.h"
 #include "clang_complete.h"
 #include "message_handler.h"
+#include "project.h"
 #include "working_files.h"
+#include "queue_manager.h"
+
+#include <loguru/loguru.hpp>
 
 namespace {
 struct Ipc_TextDocumentDidChange
@@ -17,6 +22,18 @@ struct TextDocumentDidChangeHandler
   void Run(Ipc_TextDocumentDidChange* request) override {
     std::string path = request->params.textDocument.uri.GetPath();
     working_files->OnChange(request->params);
+    if (config->enableIndexOnDidChange) {
+      optional<std::string> content = ReadContent(path);
+      if (!content) {
+        LOG_S(ERROR) << "Unable to read file content after saving " << path;
+      } else {
+        Project::Entry entry = project->FindCompilationEntryForFile(path);
+        QueueManager::instance()->index_request.PushBack(
+            Index_Request(entry.filename, entry.args, true /*is_interactive*/,
+                          *content, ICacheManager::Make(config)),
+            true);
+      }
+    }
     clang_complete->NotifyEdit(path);
     clang_complete->DiagnosticsUpdate(
         std::monostate(),
diff --git a/src/messages/text_document_did_save.cc b/src/messages/text_document_did_save.cc
index f7629287..3635d767 100644
--- a/src/messages/text_document_did_save.cc
+++ b/src/messages/text_document_did_save.cc
@@ -34,7 +34,8 @@ struct TextDocumentDidSaveHandler
     // Send out an index request, and copy the current buffer state so we
     // can update the cached index contents when the index is done.
     //
-    // We also do not index if there is already an index request.
+    // We also do not index if there is already an index request or if
+    // the client requested indexing on didChange instead.
     //
     // TODO: Cancel outgoing index request. Might be tricky to make
     //       efficient since we have to cancel.
@@ -44,15 +45,17 @@ struct TextDocumentDidSaveHandler
     //      mutex and check to see if we should skip the current request.
     //      if so, ignore that index response.
     // TODO: send as priority request
-    optional<std::string> content = ReadContent(path);
-    if (!content) {
-      LOG_S(ERROR) << "Unable to read file content after saving " << path;
-    } else {
-      Project::Entry entry = project->FindCompilationEntryForFile(path);
-      QueueManager::instance()->index_request.PushBack(
-          Index_Request(entry.filename, entry.args, true /*is_interactive*/,
-                        *content, ICacheManager::Make(config)),
-          true);
+    if (!config->enableIndexOnDidChange) {
+      optional<std::string> content = ReadContent(path);
+      if (!content) {
+        LOG_S(ERROR) << "Unable to read file content after saving " << path;
+      } else {
+        Project::Entry entry = project->FindCompilationEntryForFile(path);
+        QueueManager::instance()->index_request.PushBack(
+            Index_Request(entry.filename, entry.args, true /*is_interactive*/,
+                          *content, ICacheManager::Make(config)),
+            true);
+      }
     }
 
     clang_complete->NotifySave(path);