2 * Copyright 2014-present Facebook, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
21 #include <folly/portability/SysTypes.h>
26 * A class for tracking time durations in test code.
28 * This is primarily useful for testing timeout functionality. When comparing
29 * the differences between two TimePoints, it can exclude time spent waiting on
30 * the OS scheduler. This helps avoid spurious test failures when timeouts are
31 * exceeded by longer than expected simply because the underlying system was
32 * busy and could not schedule this thread in time.
36 explicit TimePoint(bool set = true)
45 bool isUnset() const {
46 return (timeStart_.time_since_epoch().count() == 0 &&
47 timeEnd_.time_since_epoch().count() == 0 &&
48 timeWaiting_.count() == 0);
51 std::chrono::steady_clock::time_point getTime() const {
55 std::chrono::steady_clock::time_point getTimeStart() const {
59 std::chrono::steady_clock::time_point getTimeEnd() const {
63 std::chrono::nanoseconds getTimeWaiting() const {
67 pid_t getTid() const {
72 std::chrono::steady_clock::time_point timeStart_;
73 std::chrono::steady_clock::time_point timeEnd_;
74 std::chrono::nanoseconds timeWaiting_{0};
78 std::ostream& operator<<(std::ostream& os, const TimePoint& timePoint);
81 const TimePoint& start,
83 std::chrono::nanoseconds expected,
85 std::chrono::nanoseconds tolerance = std::chrono::milliseconds(5));