Use wait-in-destruct future everywhere

Summary:
Before we used `utils::Future` only where it's created by our `ThreadPool`.
I suggest in this diff that we use it everywhere, it's a bit more defensive and
should not have any downsides.

Reviewers: msantl, teon.banek

Reviewed By: msantl

Subscribers: pullbot

Differential Revision: https://phabricator.memgraph.io/D1316

src/database/graph_db_accessor.cpp

@@ -1,5 +1,4 @@
 #include <functional>
-#include <future>
 
 #include "glog/logging.h"
 

src/query/plan/operator.cpp

@@ -1,7 +1,6 @@
 #include "query/plan/operator.hpp"
 
 #include <algorithm>
-#include <future>
 #include <limits>
 #include <queue>
 #include <random>
@@ -26,7 +25,6 @@
 #include "query/path.hpp"
 #include "utils/algorithm.hpp"
 #include "utils/exceptions.hpp"
-#include "utils/future.hpp"
 
 DEFINE_HIDDEN_int32(remote_pull_sleep_micros, 10,
                     "Sleep between remote result pulling in microseconds");
@@ -553,10 +551,9 @@ bool Expand::ExpandCursor::Pull(Frame &frame, Context &context) {
   };
 
   auto find_ready_future = [this]() {
-    return std::find_if(future_expands_.begin(), future_expands_.end(),
-                        [](const auto &future) {
-                          return utils::IsFutureReady(future.edge_to);
-                        });
+    return std::find_if(
+        future_expands_.begin(), future_expands_.end(),
+        [](const auto &future) { return future.edge_to.IsReady(); });
   };
 
   auto put_future_edge_on_frame = [this, &frame](auto &future) {

src/query/plan/operator.hpp

@@ -3,7 +3,6 @@
 #pragma once
 
 #include <experimental/optional>
-#include <future>
 #include <memory>
 #include <unordered_map>
 #include <unordered_set>
@@ -24,6 +23,7 @@
 #include "query/typed_value.hpp"
 #include "storage/types.hpp"
 #include "utils/bound.hpp"
+#include "utils/future.hpp"
 #include "utils/hashing/fnv.hpp"
 #include "utils/visitor.hpp"
 
@@ -828,7 +828,7 @@ class Expand : public LogicalOperator, public ExpandCommon {
 
    private:
     struct FutureExpand {
-      std::future<std::pair<EdgeAccessor, VertexAccessor>> edge_to;
+      utils::Future<std::pair<EdgeAccessor, VertexAccessor>> edge_to;
       std::vector<TypedValue> frame_elems;
     };
 

src/threading/thread_pool.hpp

@@ -3,7 +3,6 @@
 
 #include <condition_variable>
 #include <functional>
-#include <future>
 #include <memory>
 #include <mutex>
 #include <queue>

src/utils/algorithm.hpp

@@ -2,7 +2,6 @@
 
 #include <algorithm>
 #include <chrono>
-#include <future>
 #include <string>
 #include <utility>
 
@@ -125,15 +124,4 @@ class Iterable {
   TIterator end_;
 };
 
-/**
- * Returns true if the future has the result available.
- * NOTE: The behaviour is undefined if future isn't valid, i.e.
- * `future.valid() == false`.
- */
-template <typename T>
-bool IsFutureReady(const std::future<T> &future) {
-  auto status = future.wait_for(std::chrono::seconds(0));
-  return status == std::future_status::ready;
-}
-
 }  // namespace utils