Then chaining still kinda broken

test/Engine/CMakeLists.txt

@@ -1,8 +1,10 @@
 target_sources(Seele_unit_tests
 	PRIVATE
 		../../src/Engine/MinimalEngine.cpp
+		../../src/Engine/ThreadPool.cpp
 		EngineTest.h
-		EngineTest.cpp)
+		EngineTest.cpp
+		ThreadPool.cpp)
 target_include_directories(Seele_unit_tests PUBLIC ./)
 add_subdirectory(Containers/)
 add_subdirectory(Graphics/)

test/Engine/ThreadPool.cpp

@@ -0,0 +1,74 @@
+#include "EngineTest.h"
+#include "ThreadPool.h"
+#include <boost/test/unit_test.hpp>
+
+BOOST_AUTO_TEST_SUITE(ThreadPool)
+
+uint64 basicJobState = 0;
+
+Job basicThenFirst()
+{
+    basicJobState = 10;
+    co_return;
+}
+Job basicThenSecond()
+{
+    BOOST_REQUIRE_EQUAL(basicJobState, 10);
+    basicJobState = 20;
+    co_return;
+}
+Job basicThenThird()
+{
+    BOOST_REQUIRE_EQUAL(basicJobState, 20);
+    co_return;
+}
+
+BOOST_AUTO_TEST_CASE(basic_then)
+{
+    basicThenFirst()
+        .then(basicThenSecond())
+        .then(basicThenThird());
+}
+
+uint64 basicAllState1 = 0;
+uint64 basicAllState2 = 0;
+Job basicAllFirst()
+{
+    basicAllState1 = 10;
+    co_return;
+}
+Job basicAllSecond()
+{
+    basicAllState2 = 10;
+    co_return;
+}
+Job basicAllThen()
+{
+    BOOST_REQUIRE_EQUAL(basicAllState1, 10);
+    BOOST_REQUIRE_EQUAL(basicAllState2, 10);
+    co_return;
+}
+
+BOOST_AUTO_TEST_CASE(basic_all)
+{
+    Job::all(basicAllFirst(), basicAllSecond()).then(basicAllThen());
+}
+
+uint64 basicCallable = 0;
+
+Job basicCallableFunc()
+{
+    basicCallable = 10;
+    co_return;
+}
+
+BOOST_AUTO_TEST_CASE(basic_callable)
+{
+    basicCallableFunc()
+        .then([=]() -> Job{
+            BOOST_REQUIRE_EQUAL(basicCallable, 10);
+            co_return;
+        });
+}
+
+BOOST_AUTO_TEST_SUITE_END()