➕ make strong_ptr transitive dependency + enhancements (#21)

- Make strong_ptr a transitive dependency
- Implement C++20 modules support with proper export declarations
- Update CMake configuration to use async_context-config.cmake and
  include EXPORT_PACKAGE_DEPENDENCIES
- Refactor async_context module to use export keywords for all
  types, classes, and enums
- Add test_package with CMakeLists.txt and conanfile.py for module
  testing
- Add .clangd configuration for better module development support
- Update conanfile.py to:
  - Include .cmake.in files in exports_sources
  - Use cmake/[^4.0.0] and ninja/[^1.3.0] as tool requirements
  - Update strong_ptr dependency to version 0.0.2 with transitive
    headers/libs enabled
- Remove std::function callback usage and replace with strong_ptr
  for scheduler interface to enable entire class objects as
  schedulers rather than just function wrappers
- Fix unit test execution by moving "Executing unit tests!" message
  to build phase and updating the test runner to use modern C++20
- Update async_context module to remove unused functional header
  and properly export all types and templates
- Add comprehensive test for coroutine double delay functionality
- Enhance scheduler test to properly handle chrono::nanoseconds
  type in variant

Author: kammce

.github/workflows/ci.yml

@@ -24,4 +24,7 @@ on:
 jobs:
   package_and_upload_all_check:
     uses: libhal/ci/.github/workflows/package_and_upload_all.yml@5.x.y
+    with:
+      modules_support_needed: true
+      coroutine_support_needed: true
     secrets: inherit

.github/workflows/deploy.yml

@@ -26,6 +26,8 @@ jobs:
     with:
       version: ${{ github.ref_name }}
       remote_url: https://libhal.jfrog.io/artifactory/api/conan/trunk-conan
+      modules_support_needed: true
+      coroutine_support_needed: true
     secrets:
       conan_remote_password: ${{ secrets.JFROG_LIBHAL_TRUNK_ID_TOKEN }}
       conan_remote_user: ${{ secrets.JFROG_LIBHAL_TRUNK_ID_TOKEN_USER }}

CMakeLists.txt

@@ -48,10 +48,10 @@ install(
 
 install(
     EXPORT async_context_targets
-    FILE "libasync_context-config.cmake"
-    NAMESPACE libasync_context::
+    FILE "async_context-config.cmake"
     DESTINATION "lib/cmake"
     CXX_MODULES_DIRECTORY "cxx-modules"
+    EXPORT_PACKAGE_DEPENDENCIES
 )
 
 # ==============================================================================
@@ -63,6 +63,7 @@ find_package(ut REQUIRED)
 if(CMAKE_CROSSCOMPILING)
     message(STATUS "Cross compiling, skipping unit test execution")
 else()
+    message(STATUS "Building unit tests!")
     add_executable(async_unit_test)
     # Add module files
     target_sources(async_unit_test
@@ -75,7 +76,6 @@ else()
     target_compile_options(async_unit_test PRIVATE -g)
     target_link_libraries(async_unit_test PRIVATE async_context Boost::ut)
 
-    message(STATUS "Executing unit tests!")
     add_custom_target(run_tests ALL DEPENDS async_unit_test COMMAND async_unit_test)
 endif()
 

conanfile.py

@@ -33,7 +33,7 @@ class async_context_conan(ConanFile):
     description = ("Implementation of C++20 coroutines targeting embedded system by eliminating the usage of the global heap and providing a 'context' which contains a coroutine stack frame and other useful utilities for scheduling.")
     topics = ("async", "coroutines", "stack", "scheduling", "scheduler")
     settings = "compiler", "build_type", "os", "arch"
-    exports_sources = "modules/*", "tests/*", "CMakeLists.txt", "LICENSE"
+    exports_sources = "modules/*", "tests/*", "CMakeLists.txt", "*.cmake.in", "LICENSE"
     package_type = "static-library"
     shared = False
 
@@ -84,12 +84,12 @@ def validate(self):
         self._validate_compiler_version()
 
     def build_requirements(self):
-        # Provides CMake, Ninja, & toolchain scripts for enabling modules
-        self.tool_requires("cmake-modules-toolchain/1.0.2")
+        self.tool_requires("cmake/[^4.0.0]")
+        self.tool_requires("ninja/[^1.3.0]")
         self.test_requires("boost-ext-ut/2.3.1")
 
     def requirements(self):
-        self.requires("strong_ptr/0.0.0")
+        self.requires("strong_ptr/0.0.2")
 
     def layout(self):
         cmake_layout(self)

modules/async_context.cppm

@@ -20,7 +20,6 @@ module;
 #include <chrono>
 #include <coroutine>
 #include <exception>
-#include <functional>
 #include <memory_resource>
 #include <new>
 #include <span>
@@ -32,14 +31,13 @@ export module async_context;
 
 export import strong_ptr;
 
-export namespace async::inline v0 {
+namespace async::inline v0 {
 
-using u8 = std::uint8_t;
-using byte = std::uint8_t;
-using usize = std::size_t;
+export using u8 = std::uint8_t;
+export using byte = std::uint8_t;
+export using usize = std::size_t;
 
-enum class blocked_by : u8
-{
+export enum class blocked_by : u8 {
   /// Not blocked by anything, ready to run!
   nothing = 0,
 
@@ -63,7 +61,7 @@ enum class blocked_by : u8
   external = 4,
 };
 
-class context;
+export class context;
 
 /**
  * @brief Thrown when an async::context runs out of stack memory
@@ -72,7 +70,7 @@ class context;
  * cannot fit withint he context.
  *
  */
-struct bad_coroutine_alloc : std::bad_alloc
+export struct bad_coroutine_alloc : std::bad_alloc
 {
   bad_coroutine_alloc(context const* p_violator)
     : violator(p_violator)
@@ -117,7 +115,7 @@ using sleep_duration = std::chrono::nanoseconds;
  * @brief
  *
  */
-class scheduler
+export class scheduler
 {
 public:
   /**
@@ -156,7 +154,7 @@ private:
     std::variant<sleep_duration, context*> p_block_info) = 0;
 };
 
-class context
+export class context
 {
 public:
   static auto constexpr default_timeout = sleep_duration(0);
@@ -415,10 +413,10 @@ protected:
   class context* m_context;
 };
 
-template<typename T>
+export template<typename T>
 class future;
 
-template<typename T>
+export template<typename T>
 class future_promise_type : public promise_base
 {
 public:
@@ -505,7 +503,7 @@ private:
   usize m_frame_size;
 };
 
-template<>
+export template<>
 class future_promise_type<void> : public promise_base
 {
 public:
@@ -589,7 +587,7 @@ private:
   usize m_frame_size = 0;
 };
 
-template<typename T>
+export template<typename T>
 class future
 {
 public:
@@ -599,7 +597,7 @@ public:
 
   constexpr void resume() const
   {
-    auto active = handle().promise().context().active_handle();
+    auto active = handle().promise().get_context().active_handle();
     active.resume();
   }
 

test_package/.clangd

@@ -0,0 +1,3 @@
+CompileFlags:
+  CompilationDatabase: .
+  BuiltinHeaders: QueryDriver

test_package/CMakeLists.txt

@@ -0,0 +1,44 @@
+# Copyright 2024 - 2025 Khalil Estell and the libhal contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+cmake_minimum_required(VERSION 4.0)
+
+# Generate compile commands for anyone using our libraries.
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+set(CMAKE_COLOR_DIAGNOSTICS ON)
+
+project(test_package LANGUAGES CXX)
+
+# Require Ninja or Visual Studio for modules
+if(NOT CMAKE_GENERATOR MATCHES "Ninja|Visual Studio")
+    message(FATAL_ERROR "C++20 modules require Ninja or Visual Studio generator")
+endif()
+
+find_package(async_context REQUIRED CONFIG)
+
+add_executable(${PROJECT_NAME})
+target_sources(${PROJECT_NAME} PUBLIC
+    FILE_SET CXX_MODULES
+    TYPE CXX_MODULES
+    PRIVATE main.cpp
+)
+target_compile_features(${PROJECT_NAME} PRIVATE cxx_std_23)
+target_link_libraries(${PROJECT_NAME} PRIVATE async_context)
+
+# Always run this custom target by making it depend on ALL
+add_custom_target(copy_compile_commands ALL
+    COMMAND ${CMAKE_COMMAND} -E copy_if_different
+    ${CMAKE_BINARY_DIR}/compile_commands.json
+    ${CMAKE_SOURCE_DIR}/compile_commands.json
+    DEPENDS ${CMAKE_BINARY_DIR}/compile_commands.json)

test_package/conanfile.py

@@ -0,0 +1,52 @@
+#!/usr/bin/python
+#
+# Copyright 2024 - 2025 Khalil Estell and the libhal contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from conan import ConanFile
+from conan.tools.build import cross_building
+from conan.tools.cmake import CMake, cmake_layout, CMakeToolchain, CMakeDeps
+from pathlib import Path
+
+
+class TestPackageConan(ConanFile):
+    settings = "os", "arch", "compiler", "build_type"
+    generators = "VirtualRunEnv"
+
+    def build_requirements(self):
+        self.tool_requires("cmake/[^4.0.0]")
+        self.tool_requires("ninja/[^1.3.0]")
+
+    def requirements(self):
+        self.requires(self.tested_reference_str)
+
+    def layout(self):
+        cmake_layout(self)
+
+    def generate(self):
+        tc = CMakeToolchain(self)
+        tc.generate()
+
+        deps = CMakeDeps(self)
+        deps.generate()
+
+    def build(self):
+        cmake = CMake(self)
+        cmake.configure()
+        cmake.build()
+
+    def test(self):
+        if not cross_building(self):
+            bin_path = Path(self.cpp.build.bindirs[0]) / "test_package"
+            self.run(bin_path.absolute(), env="conanrun")

test_package/main.cpp

@@ -0,0 +1,83 @@
+// Copyright 2024 - 2025 Khalil Estell and the libhal contributors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <cassert>
+
+#include <array>
+#include <chrono>
+#include <coroutine>
+#include <memory_resource>
+#include <print>
+#include <span>
+#include <variant>
+
+import async_context;
+
+struct my_scheduler : public async::scheduler
+{
+  int sleep_count = 0;
+
+private:
+  void do_schedule(
+    [[maybe_unused]] async::context& p_context,
+    [[maybe_unused]] async::blocked_by p_block_state,
+    [[maybe_unused]] std::variant<std::chrono::nanoseconds, async::context*>
+      p_block_info) override
+  {
+    if (std::holds_alternative<std::chrono::nanoseconds>(p_block_info)) {
+      sleep_count++;
+    }
+  }
+};
+
+async::future<void> coro_double_delay(async::context&)
+{
+  using namespace std::chrono_literals;
+  std::println("Delay for 500ms");
+  co_await 500ms;
+  std::println("Delay for another 500ms");
+  co_await 500ms;
+  std::println("Returning!");
+  co_return;
+}
+
+int main()
+{
+  auto scheduler =
+    mem::make_strong_ptr<my_scheduler>(std::pmr::new_delete_resource());
+  auto buffer = mem::make_strong_ptr<std::array<async::u8, 1024>>(
+    std::pmr::new_delete_resource());
+  auto buffer_span = mem::make_strong_ptr<std::span<async::u8>>(
+    std::pmr::new_delete_resource(), *buffer);
+  async::context my_context(scheduler, buffer_span);
+
+  auto future_delay = coro_double_delay(my_context);
+
+  assert(not future_delay.done());
+
+  future_delay.resume();
+
+  assert(scheduler->sleep_count == 1);
+
+  future_delay.resume();
+
+  assert(scheduler->sleep_count == 2);
+  assert(not future_delay.done());
+
+  future_delay.resume();
+
+  assert(future_delay.done());
+
+  return 0;
+}

tests/async.test.cpp

@@ -45,14 +45,16 @@ boost::ut::suite<"async::context"> async_context_suite = []() {
       int sleep_count = 0;
 
     private:
-      void do_schedule([[maybe_unused]] context& p_context,
-                       [[maybe_unused]] blocked_by p_block_state,
-                       [[maybe_unused]] std::variant<sleep_duration, context*>
-                         p_block_info) override
+      void do_schedule(
+        [[maybe_unused]] context& p_context,
+        [[maybe_unused]] blocked_by p_block_state,
+        [[maybe_unused]] std::variant<std::chrono::nanoseconds, context*>
+          p_block_info) override
       {
         std::println("Scheduler called!", sleep_count);
-        if (std::holds_alternative<sleep_duration>(p_block_info)) {
-          std::println("sleep for: {}", std::get<sleep_duration>(p_block_info));
+        if (std::holds_alternative<std::chrono::nanoseconds>(p_block_info)) {
+          std::println("sleep for: {}",
+                       std::get<std::chrono::nanoseconds>(p_block_info));
           sleep_count++;
           std::println("Sleep count = {}!", sleep_count);
         }