Add FPS test

src/engine/internal/clock.cpp

@@ -1,5 +1,7 @@
 // SPDX-License-Identifier: Apache-2.0
 
+#include <thread>
+
 #include "clock.h"
 
 using namespace libscratchcpp;
@@ -24,3 +26,8 @@ std::chrono::system_clock::time_point Clock::currentSystemTime() const
 {
     return std::chrono::system_clock::now();
 }
+
+void Clock::sleep(const std::chrono::milliseconds &time) const
+{
+    std::this_thread::sleep_for(time);
+}

src/engine/internal/clock.h

@@ -19,6 +19,8 @@ class Clock : public IClock
         std::chrono::steady_clock::time_point currentSteadyTime() const override;
         std::chrono::system_clock::time_point currentSystemTime() const override;
 
+        void sleep(const std::chrono::milliseconds &time) const override;
+
     private:
         static std::shared_ptr<Clock> m_instance;
 };

src/engine/internal/engine.cpp

@@ -17,18 +17,19 @@
 #include <scratchcpp/keyevent.h>
 #include <cassert>
 #include <iostream>
-#include <thread>
 
 #include "engine.h"
 #include "blocksectioncontainer.h"
 #include "timer.h"
+#include "clock.h"
 #include "../../blocks/standardblocks.h"
 
 using namespace libscratchcpp;
 
 Engine::Engine() :
     m_defaultTimer(std::make_unique<Timer>()),
-    m_timer(m_defaultTimer.get())
+    m_timer(m_defaultTimer.get()),
+    m_clock(Clock::instance().get())
 {
 }
 
@@ -354,7 +355,7 @@ void Engine::run()
     start();
 
     while (true) {
-        auto lastFrameTime = std::chrono::steady_clock::now();
+        auto lastFrameTime = m_clock->currentSteadyTime();
         m_skipFrame = false;
 
         // Execute the frame
@@ -363,13 +364,13 @@ void Engine::run()
             break;
 
         // Sleep until the time for the next frame
-        auto currentTime = std::chrono::steady_clock::now();
+        auto currentTime = m_clock->currentSteadyTime();
         auto elapsedTime = std::chrono::duration_cast<std::chrono::milliseconds>(currentTime - lastFrameTime);
         auto sleepTime = m_frameDuration - elapsedTime;
         bool timeOut = sleepTime <= std::chrono::milliseconds::zero();
 
         if (!timeOut && !m_skipFrame)
-            std::this_thread::sleep_for(sleepTime);
+            m_clock->sleep(sleepTime);
 
         if ((m_skipFrame && timeOut) || !m_skipFrame) {
             // TODO: Repaint here

src/engine/internal/engine.h

@@ -15,6 +15,7 @@ namespace libscratchcpp
 {
 
 class Entity;
+class IClock;
 
 class Engine : public IEngine
 {
@@ -116,6 +117,8 @@ class Engine : public IEngine
         BlockSectionContainer *blockSectionContainer(const std::string &opcode) const;
         BlockSectionContainer *blockSectionContainer(IBlockSection *section) const;
 
+        IClock *m_clock = nullptr;
+
     private:
         void finalize();
         void deleteClones();

src/engine/internal/iclock.h

@@ -14,6 +14,8 @@ class IClock
 
         virtual std::chrono::steady_clock::time_point currentSteadyTime() const = 0;
         virtual std::chrono::system_clock::time_point currentSystemTime() const = 0;
+
+        virtual void sleep(const std::chrono::milliseconds &time) const = 0;
 };
 
 } // namespace libscratchcpp

test/engine/engine_test.cpp

@@ -6,15 +6,25 @@
 #include <scratchcpp/variable.h>
 #include <scratchcpp/list.h>
 #include <timermock.h>
+#include <clockmock.h>
 
 #include "../common.h"
 #include "testsection.h"
 #include "engine/internal/engine.h"
+#include "engine/internal/clock.h"
 
 using namespace libscratchcpp;
 
+using ::testing::Return;
+
 // NOTE: resolveIds() and compile() are tested in load_project_test
 
+TEST(EngineTest, Clock)
+{
+    Engine engine;
+    ASSERT_EQ(engine.m_clock, Clock::instance().get());
+}
+
 TEST(EngineTest, Clear)
 {
     Engine engine;
@@ -61,6 +71,33 @@ TEST(EngineTest, Fps)
     ASSERT_EQ(engine.fps(), 60.25);
 }
 
+TEST(EngineTest, FpsProject)
+{
+    Project p("2_frames.sb3");
+    ASSERT_TRUE(p.load());
+
+    ClockMock clock;
+    Engine *engine = dynamic_cast<Engine *>(p.engine().get());
+    engine->m_clock = &clock;
+
+    std::chrono::steady_clock::time_point time1(std::chrono::milliseconds(50));
+    std::chrono::steady_clock::time_point time2(std::chrono::milliseconds(75));
+    std::chrono::steady_clock::time_point time3(std::chrono::milliseconds(83));
+    std::chrono::steady_clock::time_point time4(std::chrono::milliseconds(116));
+    EXPECT_CALL(clock, currentSteadyTime()).WillOnce(Return(time1)).WillOnce(Return(time2)).WillOnce(Return(time3)).WillOnce(Return(time4)).WillOnce(Return(time4));
+    EXPECT_CALL(clock, sleep(std::chrono::milliseconds(8)));
+    p.run();
+
+    engine->setFps(10);
+    std::chrono::steady_clock::time_point time5(std::chrono::milliseconds(100));
+    std::chrono::steady_clock::time_point time6(std::chrono::milliseconds(115));
+    std::chrono::steady_clock::time_point time7(std::chrono::milliseconds(200));
+    std::chrono::steady_clock::time_point time8(std::chrono::milliseconds(300));
+    EXPECT_CALL(clock, currentSteadyTime()).WillOnce(Return(time5)).WillOnce(Return(time6)).WillOnce(Return(time7)).WillOnce(Return(time8)).WillOnce(Return(time8));
+    EXPECT_CALL(clock, sleep(std::chrono::milliseconds(85)));
+    p.run();
+}
+
 TEST(EngineTest, KeyState)
 {
     Engine engine;

test/mocks/clockmock.h

@@ -10,4 +10,6 @@ class ClockMock : public IClock
     public:
         MOCK_METHOD(std::chrono::steady_clock::time_point, currentSteadyTime, (), (const, override));
         MOCK_METHOD(std::chrono::system_clock::time_point, currentSystemTime, (), (const, override));
+
+        MOCK_METHOD(void, sleep, (const std::chrono::milliseconds &time), (const, override));
 };