From d815651455b4d77f086a598ade80faff96a1e294 Mon Sep 17 00:00:00 2001
From: Joyee Cheung <joyeec9h3@gmail.com>
Date: Wed, 14 Mar 2018 14:14:48 +0800
Subject: [PATCH] src: simplify native_immediate_callbacks

- Use std::list instead of std::vector because we do not need
  random access.
- Use list.erase instead of moving elements then resizing to
  remove the first n elements in the list for simplicity and
  avoiding reallocation.
---
 src/env.cc | 5 ++---
 src/env.h  | 2 +-
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/env.cc b/src/env.cc
index 913f0e865beb1d..f817edc0ff930d 100644
--- a/src/env.cc
+++ b/src/env.cc
@@ -369,7 +369,7 @@ void Environment::RunAndClearNativeImmediates() {
   size_t count = native_immediate_callbacks_.size();
   if (count > 0) {
     size_t ref_count = 0;
-    std::vector<NativeImmediateCallback> list;
+    std::list<NativeImmediateCallback> list;
     native_immediate_callbacks_.swap(list);
     auto drain_list = [&]() {
       v8::TryCatch try_catch(isolate());
@@ -381,8 +381,7 @@ void Environment::RunAndClearNativeImmediates() {
           FatalException(isolate(), try_catch);
           // Bail out, remove the already executed callbacks from list
           // and set up a new TryCatch for the other pending callbacks.
-          std::move_backward(it, list.end(), list.begin() + (list.end() - it));
-          list.resize(list.end() - it);
+          list.erase(list.begin(), it);
           return true;
         }
       }
diff --git a/src/env.h b/src/env.h
index e6060b9e6faab9..4a2ef983422bda 100644
--- a/src/env.h
+++ b/src/env.h
@@ -845,7 +845,7 @@ class Environment {
     std::unique_ptr<Persistent<v8::Object>> keep_alive_;
     bool refed_;
   };
-  std::vector<NativeImmediateCallback> native_immediate_callbacks_;
+  std::list<NativeImmediateCallback> native_immediate_callbacks_;
   void RunAndClearNativeImmediates();
   static void CheckImmediate(uv_check_t* handle);