Add scheduler of tests

include/beman/lazy/detail/scheduler_of.hpp

@@ -4,9 +4,17 @@
 #ifndef INCLUDED_INCLUDE_BEMAN_LAZY_DETAIL_SCHEDULER_OF
 #define INCLUDED_INCLUDE_BEMAN_LAZY_DETAIL_SCHEDULER_OF
 
+#include <beman/lazy/detail/any_scheduler.hpp>
+#include <beman/execution26/execution.hpp>
+
 // ----------------------------------------------------------------------------
 
 namespace beman::lazy::detail {
+/*!
+ * \brief Utility to get a scheduler type from a context
+ * \headerfile beman/lazy/lazy.hpp <beman/lazy/lazy.hpp>
+ * \internal
+ */
 template <typename>
 struct scheduler_of {
     using type = ::beman::lazy::detail::any_scheduler;
@@ -15,6 +23,8 @@ template <typename Context>
     requires requires { typename Context::scheduler_type; }
 struct scheduler_of<Context> {
     using type = typename Context::scheduler_type;
+    static_assert(::beman::execution26::scheduler<type>,
+                  "The type alias scheduler_type needs to refer to a scheduler");
 };
 template <typename Context>
 using scheduler_of_t = typename scheduler_of<Context>::type;

tests/beman/lazy/CMakeLists.txt

@@ -1,6 +1,14 @@
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
-list(APPEND lazy_tests any_scheduler inline_scheduler lazy poly)
+list(
+    APPEND
+    lazy_tests
+    any_scheduler
+    inline_scheduler
+    lazy
+    poly
+    scheduler_of
+)
 
 foreach(test ${lazy_tests})
     add_executable(beman.lazy.tests.${test})

tests/beman/lazy/any_scheduler.test.cpp

@@ -31,7 +31,6 @@ struct thread_context {
         virtual void complete() = 0;
     };
 
-    std::latch              stop_done{1u};
     std::mutex              mutex;
     std::condition_variable condition;
     bool                    done{false};
@@ -60,7 +59,6 @@ struct thread_context {
               while (auto w{this->get_work()}) {
                   w->complete();
               }
-              this->stop_done.count_down();
           }) {}
     ~thread_context() {
         this->stop();
@@ -145,7 +143,6 @@ struct thread_context {
             this->done = true;
         }
         this->condition.notify_one();
-        this->stop_done.wait();
     }
 };
 

tests/beman/lazy/scheduler_of.test.cpp

@@ -0,0 +1,33 @@
+// tests/beman/lazy/scheduler_of.test.cpp                             -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#include <beman/lazy/detail/scheduler_of.hpp>
+#include <beman/lazy/detail/any_scheduler.hpp>
+#include <beman/lazy/detail/inline_scheduler.hpp>
+#include <concepts>
+#ifdef NDEBUG
+#undef NDEBUG
+#endif
+#include <cassert>
+
+// ----------------------------------------------------------------------------
+
+namespace {
+struct no_scheduler {};
+
+struct defines_scheduler {
+    using scheduler_type = beman::lazy::detail::inline_scheduler;
+};
+
+struct non_scheduler {};
+struct defines_non_scheduler {
+    using scheduler_type = non_scheduler;
+};
+} // namespace
+
+int main() {
+    static_assert(std::same_as<beman::lazy::detail::any_scheduler, beman::lazy::detail::scheduler_of_t<no_scheduler>>);
+    static_assert(
+        std::same_as<beman::lazy::detail::inline_scheduler, beman::lazy::detail::scheduler_of_t<defines_scheduler>>);
+    // using type = beman::lazy::detail::scheduler_of_t<defines_non_scheduler>;
+}