From a0b10b4c505f4cab75cb8e1ecd4cd7c23d8beef5 Mon Sep 17 00:00:00 2001
From: Henry Fredrick Schreiner <henry.fredrick.schreiner@cern.ch>
Date: Wed, 22 Mar 2017 10:40:00 -0400
Subject: [PATCH] Adding timer

---
 CHANGELOG.md          |  1 +
 include/CLI/Timer.hpp | 74 +++++++++++++++++++++++++++++++++++++++++++
 tests/CMakeLists.txt  | 12 +++++++
 tests/TimerTest.cpp   | 53 +++++++++++++++++++++++++++++++
 4 files changed, 140 insertions(+)
 create mode 100644 include/CLI/Timer.hpp
 create mode 100644 tests/TimerTest.cpp

diff --git a/CHANGELOG.md b/CHANGELOG.md
index df3f902a..beb1c553 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@
 * Lots of small bugfixes related to adding tests to increase coverage
 * Error handling now uses scoped enum in errors
 * Reparsing rules changed a little to accommodate Ini files. Callbacks are now called when parsing INI, and reset any time results are added.
+* Adding extra utilities in seperate files version only, `Timer` (not needed for parsing, but useful for general CLI applications).
 
 ## Version 0.6
 
diff --git a/include/CLI/Timer.hpp b/include/CLI/Timer.hpp
new file mode 100644
index 00000000..c34768d3
--- /dev/null
+++ b/include/CLI/Timer.hpp
@@ -0,0 +1,74 @@
+#pragma once
+
+// Distributed under the LGPL v2.1 license.  See accompanying
+// file LICENSE or https://github.com/henryiii/CLI11 for details.
+
+#include <string>
+#include <iostream>
+#include <chrono>
+#include <functional>
+
+namespace CLI {
+
+class Timer {
+protected:
+    typedef std::chrono::high_resolution_clock clock;
+    typedef std::chrono::time_point<clock> time_point;
+    typedef std::function<std::string(std::string, std::string)> time_print_t;
+
+    std::string title_;
+    time_point start_;
+    time_print_t time_print_;
+public:
+    static std::string Simple(std::string title, std::string time) {
+        return title + ": " + time;
+    }
+
+    static std::string Big(std::string title, std::string time) {
+        return "-----------------------------------------\n"
+            + title + " | Time = " + time + "\n"
+            + "-----------------------------------------";
+    }
+
+public:
+    Timer(std::string title="Timer", time_print_t time_print = Simple)
+        : title_(title), time_print_(time_print), start_(clock::now()) {}
+
+
+    std::string make_time_str() const {
+        time_point stop = clock::now();
+        std::chrono::duration<double, std::milli> elapsed = stop - start_;
+        double time = elapsed.count();
+        
+        // LCOV_EXCL_START
+        if(time < 1)
+            return std::to_string(int(time*1000000)) + " ns";
+        else if(time < 10)
+            return std::to_string(int(time*100) / 100.) + " ms";
+        else if(time < 1000)
+            return std::to_string(int(time)) + " ms";
+        else if(time < 10000)
+            return std::to_string(int(time*10000) / 10. ) + " s";
+        else
+            return std::to_string(int(time*1000)) + " s";
+        // LCOV_EXCL_END
+    }
+    std::string to_string() const {
+        return time_print_(title_, make_time_str());
+    }
+};
+
+class AutoTimer : public Timer {
+public:
+    using Timer::Timer;
+
+    ~AutoTimer () {
+        std::cout << to_string() << std::endl;
+    }
+};
+
+}
+
+std::ostream & operator<< (std::ostream& in, const CLI::Timer& timer) {
+    return in << timer.to_string();
+}
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 67440a2e..78579a22 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -9,6 +9,10 @@ set(CLI_TESTS
     SubcommandTest
     HelpTest)
 
+set(CLI_SINGLE_TESTS
+    TimerTest
+    )
+
 # Only affects current directory, so safe
 include_directories(${CMAKE_CURRENT_SOURCE_DIR})
 
@@ -26,3 +30,11 @@ foreach(T ${CLI_TESTS})
 
 endforeach()
 
+foreach(T ${CLI_SINGLE_TESTS})
+
+    add_executable(${T} ${T}.cpp ${CLI_headers})
+    target_link_libraries(${T} PUBLIC CLI)
+    add_gtest(${T})
+
+endforeach()
+
diff --git a/tests/TimerTest.cpp b/tests/TimerTest.cpp
new file mode 100644
index 00000000..c9366ce5
--- /dev/null
+++ b/tests/TimerTest.cpp
@@ -0,0 +1,53 @@
+#include "gtest/gtest.h"
+#include "gmock/gmock.h"
+#include "CLI/Timer.hpp"
+#include <string>
+#include <chrono>
+#include <thread>
+#include <sstream>
+
+using ::testing::HasSubstr;
+
+TEST(Timer, MSTimes) {
+    CLI::Timer timer{"My Timer"};
+    std::this_thread::sleep_for(std::chrono::milliseconds(123));
+    std::string output = timer.to_string();
+    EXPECT_THAT(output, HasSubstr("My Timer"));
+    EXPECT_THAT(output, HasSubstr(" ms"));
+}
+
+/* Takes too long
+TEST(Timer, STimes) {
+    CLI::Timer timer;
+    std::this_thread::sleep_for(std::chrono::seconds(1));
+    std::string output = timer.to_string();
+    EXPECT_THAT(output, HasSubstr(" s"));
+}
+*/
+
+TEST(Timer, NStimes) {
+    CLI::Timer timer;
+    std::string output = timer.to_string();
+    EXPECT_THAT(output, HasSubstr(" ns"));
+}
+
+TEST(Timer, BigTimer) {
+    CLI::Timer timer{"My Timer", CLI::Timer::Big};
+    std::string output = timer.to_string();
+    EXPECT_THAT(output, HasSubstr("Time ="));
+    EXPECT_THAT(output, HasSubstr("-----------"));
+}
+
+TEST(Timer, AutoTimer) {
+    CLI::AutoTimer timer;
+    std::string output = timer.to_string();
+    EXPECT_THAT(output, HasSubstr("Timer"));
+}
+
+TEST(Timer, PrintTimer) {
+    std::stringstream out;
+    CLI::AutoTimer timer;
+    out << timer;
+    std::string output = out.str();
+    EXPECT_THAT(output, HasSubstr("Timer"));
+}