add scheduler tests

tests/sched/run_loop/intrusive.cpp

@@ -0,0 +1,36 @@
+#include <fiber/sched/run_loop.hpp>
+
+#include <gtest/gtest.h>
+#include <fmt/core.h>
+
+using namespace fiber;  // NOLINT
+
+class RunLoopTest : public ::testing::Test {};
+
+TEST_F(RunLoopTest, JustWorksIntrusive) {
+  sched::RunLoop loop;
+
+  bool flag = false;
+
+  class SetFlag : public sched::task::TaskBase {
+   public:
+    explicit SetFlag(bool& flag)
+        : flag_(flag) {
+    }
+
+    void Run() noexcept override {
+      flag_ = true;
+    }
+
+   private:
+    bool& flag_;
+  };
+
+  {
+    SetFlag set{flag};
+    loop.Submit(&set);
+    loop.RunNext();
+  }
+
+  EXPECT_TRUE(flag);
+}

tests/sched/run_loop/unit.cpp

@@ -0,0 +1,106 @@
+#include <fiber/sched/run_loop.hpp>
+#include <fiber/sched/task/submit.hpp>
+
+#include <gtest/gtest.h>
+#include <fmt/core.h>
+
+using namespace fiber;  // NOLINT
+
+class RunLoopTest : public ::testing::Test {};
+
+TEST_F(RunLoopTest, JustWorks) {
+  sched::RunLoop loop;
+
+  size_t step = 0;
+
+  EXPECT_FALSE(loop.NonEmpty());
+
+  EXPECT_FALSE(loop.RunNext());
+  EXPECT_EQ(loop.RunAtMost(99), 0);
+
+  sched::task::Submit(loop, [&] {
+    step = 1;
+  });
+
+  EXPECT_TRUE(loop.NonEmpty());
+  EXPECT_EQ(step, 0);
+
+  sched::task::Submit(loop, [&] {
+    step = 2;
+  });
+
+  EXPECT_EQ(step, 0);
+  EXPECT_TRUE(loop.RunNext());
+  EXPECT_EQ(step, 1);
+  EXPECT_TRUE(loop.NonEmpty());
+
+  sched::task::Submit(loop, [&] {
+    step = 3;
+  });
+
+  EXPECT_EQ(loop.RunAtMost(99), 2);
+  EXPECT_EQ(step, 3);
+  EXPECT_FALSE(loop.NonEmpty());
+  EXPECT_FALSE(loop.RunNext());
+}
+
+TEST_F(RunLoopTest, Empty) {
+  sched::RunLoop loop;
+
+  EXPECT_FALSE(loop.RunNext());
+  EXPECT_EQ(loop.RunAtMost(7), 0);
+  EXPECT_EQ(loop.Run(), 0);
+}
+
+void Countdown(sched::RunLoop& loop, size_t k) {
+  if (k > 0) {
+    sched::task::Submit(loop, [&loop, k] {
+      Countdown(loop, k - 1);
+    });
+  }
+}
+
+TEST_F(RunLoopTest, RunAtMost) {
+  sched::RunLoop loop;
+
+  Countdown(loop, 256);
+
+  size_t tasks = 0;
+  do {
+    tasks += loop.RunAtMost(7);
+  } while (loop.NonEmpty());
+
+  fmt::println("{}", tasks);
+
+  EXPECT_EQ(tasks, 256);
+}
+
+TEST_F(RunLoopTest, RunAtMostNewTasks) {
+  sched::RunLoop loop;
+
+  sched::task::Submit(loop, [&]() {
+    sched::task::Submit(loop, []() {});
+  });
+
+  EXPECT_EQ(loop.RunAtMost(2), 2);
+}
+
+TEST_F(RunLoopTest, Run) {
+  sched::RunLoop loop;
+
+  Countdown(loop, 117);
+
+  EXPECT_EQ(loop.Run(), 117);
+}
+
+TEST_F(RunLoopTest, RunTwice) {
+  sched::RunLoop loop;
+
+  Countdown(loop, 11);
+
+  EXPECT_EQ(loop.Run(), 11);
+
+  Countdown(loop, 7);
+
+  EXPECT_EQ(loop.Run(), 7);
+}

tests/sched/thread_pool/intrusive.cpp

@@ -0,0 +1,40 @@
+#include <fiber/sched/thread_pool.hpp>
+#include <fiber/sync/wait_group.hpp>
+
+#include <gtest/gtest.h>
+#include <fmt/core.h>
+
+using namespace fiber;  // NOLINT
+
+class ThreadPoolTest : public ::testing::Test {};
+
+TEST_F(ThreadPoolTest, JustWorksIntrusive) {
+  sched::ThreadPool pool{4};
+  pool.Start();
+
+  class DoWork : public sched::task::TaskBase {
+   public:
+    explicit DoWork(sync::WaitGroup& wg)
+        : wg_(wg) {
+    }
+
+    void Run() noexcept override {
+      wg_.Done();
+    }
+
+   private:
+    sync::WaitGroup& wg_;
+  };
+
+  {
+    sync::WaitGroup wg;
+
+    DoWork work{wg};
+
+    wg.Add(1);
+    pool.Submit(&work);
+    wg.Wait();
+  }
+
+  pool.Stop();
+}