Functionality in main Cron class.

libcron/CMakeLists.txt

@@ -15,4 +15,4 @@ add_library(${PROJECT_NAME}
         CronData.cpp
         CronSchedule.cpp
         CronSchedule.h
-        externals/date/date.h DateTime.h)
+        externals/date/date.h DateTime.h Task.cpp)

libcron/Cron.cpp

@@ -1,14 +1,29 @@
 #include <functional>
 #include "Cron.h"
 
-bool libcron::Cron::add_schedule(const std::string &schedule, std::function<void()> work)
+namespace libcron
 {
-    auto cron = CronData::create(schedule);
-    bool res = cron.is_valid();
-    if (res)
+
+    bool libcron::Cron::add_schedule(const std::string& schedule, std::function<void()> work)
     {
-        items.emplace(Task(CronSchedule(cron), std::move(work)));
+        auto cron = CronData::create(schedule);
+        bool res = cron.is_valid();
+        if (res)
+        {
+            CronSchedule s(cron);
+            Task t(std::move(s), std::move(work));
+            if (t.calculate_next())
+            {
+                items.emplace(t);
+            }
+        }
+
+        return res;
     }
 
-    return res;
-}
+    bool libcron::Cron::has_expired_task(const std::chrono::system_clock::time_point now) const
+    {
+        return !items.empty() && items.top().is_expired(now);
+    }
+
+}

libcron/Cron.h

@@ -10,9 +10,17 @@ namespace libcron
     class Cron
     {
 
-    public:
-        bool add_schedule(const std::string& schedule, std::function<void()> work);
-    private:
-        std::priority_queue<Task> items{};
+        public:
+            bool add_schedule(const std::string& schedule, std::function<void()> work);
+
+            size_t count() const
+            {
+                return items.size();
+            }
+
+            bool has_expired_task(std::chrono::system_clock::time_point now = std::chrono::system_clock::now()) const;
+
+        private:
+            std::priority_queue<Task> items{};
     };
 }

libcron/CronSchedule.h

@@ -10,8 +10,8 @@ namespace libcron
     class CronSchedule
     {
         public:
-            explicit CronSchedule(CronData data)
-                    : data(std::move(data))
+            explicit CronSchedule(CronData& data)
+                    : data(data)
             {
             }
 
@@ -37,7 +37,6 @@ namespace libcron
                 return dt;
             }
 
-
         private:
             CronData data;
     };

libcron/Task.cpp

@@ -0,0 +1,17 @@
+#include "Task.h"
+
+namespace libcron
+{
+
+    bool Task::calculate_next(std::chrono::system_clock::time_point from)
+    {
+        auto result = schedule.calculate_from(from);
+        auto res = std::get<0>(result);
+        if(res)
+        {
+            next_schedule = std::get<1>(result);
+        }
+
+        return res;
+    }
+}

libcron/Task.h

@@ -3,6 +3,7 @@
 #include <functional>
 #include "CronData.h"
 #include "CronSchedule.h"
+#include <chrono>
 
 namespace libcron
 {
@@ -11,7 +12,7 @@ namespace libcron
         public:
 
             Task(CronSchedule schedule, std::function<void()> task)
-                    : schedule(std::move(schedule))//, task(std::move(task))
+                    : schedule(std::move(schedule)), task(std::move(task))
             {
             }
 
@@ -19,13 +20,21 @@ namespace libcron
 
             Task& operator=(const Task&) = default;
 
+            bool calculate_next(std::chrono::system_clock::time_point from = std::chrono::system_clock::now());
+
             bool operator<(const Task& other) const
             {
-                return false;
+                return next_schedule < other.next_schedule;
+            }
+
+            bool is_expired(std::chrono::system_clock::time_point now = std::chrono::system_clock::now()) const
+            {
+                return now >= next_schedule;
             }
 
         private:
             CronSchedule schedule;
-            //std::function<void()> task;
+            std::chrono::system_clock::time_point next_schedule;
+            std::function<void()> task;
     };
 }

test/CMakeLists.txt

@@ -12,7 +12,7 @@ include_directories(
 
 add_executable(
         ${PROJECT_NAME}
-        test.cpp
-        CronScheduleTest.cpp)
+        CronDataTest.cpp
+        CronScheduleTest.cpp CronTest.cpp)
 
 target_link_libraries(${PROJECT_NAME} libcron)

test/CronScheduleTest.cpp

@@ -178,6 +178,6 @@ SCENARIO("Multiple calculations")
 
 SCENARIO("Unable to calculate time point")
 {
-    // TODO: Find a
+    // TODO: Find a schedule that is unsolvable.
     //REQUIRE_FALSE(test("0 0 0 1 1 0", DT(2021_y / 12 / 15), DT(2022_y / 1 / 1)));
 }

test/CronTest.cpp

@@ -0,0 +1,92 @@
+#include <catch.hpp>
+#include <libcron/Cron.h>
+#include <thread>
+
+using namespace libcron;
+using namespace std::chrono;
+
+std::string create_schedule_expiring_in(hours h, minutes m, seconds s)
+{
+    auto now = system_clock::now() + h + m + s;
+    auto dt = CronSchedule::to_calendar_time(now);
+
+    std::string res = "";
+    res += std::to_string(dt.sec) + " ";
+    res += std::to_string(dt.min) + " ";
+    res += std::to_string(dt.hour) + " * * *";
+
+    return res;
+}
+
+
+SCENARIO("Adding a task")
+{
+    GIVEN("A Cron instance with no task")
+    {
+        Cron c;
+
+        THEN("Starts with no task")
+        {
+            REQUIRE(c.count() == 0);
+        }
+
+        WHEN("Adding a task that runs every second")
+        {
+            REQUIRE(c.add_schedule("* * * * * *",
+                                   []()
+                                   {
+                                       return;
+                                   })
+            );
+
+            THEN("Count is 1 and task was not expired two seconds ago")
+            {
+                REQUIRE(c.count() == 1);
+                REQUIRE_FALSE(c.has_expired_task(system_clock::now() - 2s));
+            }
+            AND_THEN("Task is expired when calculating based on current time")
+            {
+                THEN("Task is expired")
+                {
+                    REQUIRE(c.has_expired_task());
+                }
+            }
+        }
+    }
+}
+
+SCENARIO("Adding a task that expires in the future")
+{
+    GIVEN("A Cron instance with task expiring in 3 seconds")
+    {
+        Cron c;
+        REQUIRE(c.add_schedule(create_schedule_expiring_in(hours{0}, minutes{0}, seconds{3}),
+                               []()
+                               {
+                                   return;
+                               })
+        );
+
+        THEN("Not yet expired")
+        {
+            REQUIRE_FALSE(c.has_expired_task());
+        }
+        AND_WHEN("When waiting one second")
+        {
+            std::this_thread::sleep_for(1s);
+            THEN("Task has not yet expired")
+            {
+                REQUIRE_FALSE(c.has_expired_task());
+            }
+        }
+        AND_WHEN("When waiting three seconds")
+        {
+            std::this_thread::sleep_for(3s);
+            THEN("Task has expired")
+            {
+                REQUIRE(c.has_expired_task());
+            }
+        }
+    }
+}
+