test: add unit tests for spawn()

asio/src/tests/Makefile.am

@@ -221,6 +221,11 @@ check_PROGRAMS += \
 endif
 endif
 
+if HAVE_BOOST_COROUTINE
+check_PROGRAMS += \
+	unit/spawn
+endif
+
 if HAVE_OPENSSL
 check_PROGRAMS += \
 	unit/ssl/context_base \
@@ -406,6 +411,11 @@ TESTS += \
 	unit/experimental/parallel_group
 endif
 
+if HAVE_BOOST_COROUTINE
+TESTS += \
+	unit/spawn
+endif
+
 if HAVE_CXX20
 TESTS += \
 	unit/experimental/promise
@@ -630,6 +640,11 @@ unit_experimental_concurrent_channel_SOURCES = unit/experimental/concurrent_chan
 unit_experimental_parallel_group_SOURCES = unit/experimental/parallel_group.cpp
 endif
 
+if HAVE_BOOST_COROUTINE
+unit_spawn_SOURCES = unit/spawn.cpp
+unit_spawn_LDADD = -lboost_coroutine -lboost_context
+endif
+
 if HAVE_CXX20
 unit_experimental_promise_SOURCES = unit/experimental/promise.cpp
 

asio/src/tests/unit/spawn.cpp

@@ -0,0 +1,230 @@
+//
+// spawn.cpp
+// ~~~~~~~~~~~~
+//
+// Copyright (c) 2024 Casey Bodley (cbodley at redhat dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+// Disable autolinking for unit tests.
+#if !defined(BOOST_ALL_NO_LIB)
+#define BOOST_ALL_NO_LIB 1
+#endif // !defined(BOOST_ALL_NO_LIB)
+
+// Test that header file is self-contained.
+#include "asio/spawn.hpp"
+
+#include "unit_test.hpp"
+
+#include <stdexcept>
+#include "asio/any_completion_handler.hpp"
+#include "asio/bind_cancellation_slot.hpp"
+#include "asio/deferred.hpp"
+#include "asio/io_context.hpp"
+#include "asio/steady_timer.hpp"
+
+void void_returning_coroutine(asio::yield_context)
+{
+}
+
+int int_returning_coroutine(asio::yield_context)
+{
+  return 42;
+}
+
+void test_spawn_with_any_completion_handler()
+{
+  asio::io_context ctx;
+
+  bool called = false;
+  asio::spawn(ctx, void_returning_coroutine,
+      asio::any_completion_handler<void(std::exception_ptr)>(
+        [&](std::exception_ptr)
+        {
+          called = true;
+        }));
+
+  ASIO_CHECK(!called);
+
+  ctx.run();
+
+  ASIO_CHECK(called);
+
+  int result = 0;
+  asio::spawn(ctx, int_returning_coroutine,
+      asio::any_completion_handler<void(std::exception_ptr, int)>(
+        [&](std::exception_ptr, int i)
+        {
+          result = i;
+        }));
+
+  ASIO_CHECK(result == 0);
+
+  ctx.restart();
+  ctx.run();
+
+  ASIO_CHECK(result == 42);
+}
+
+void test_spawn_deferred()
+{
+  asio::io_context ctx;
+
+  {
+    bool called = false;
+    auto fn = asio::spawn(ctx, void_returning_coroutine, asio::deferred);
+
+    fn([&](std::exception_ptr)
+        {
+          called = true;
+        });
+
+    ASIO_CHECK(!called);
+
+    ctx.poll();
+
+    ASIO_CHECK(ctx.stopped());
+    ASIO_CHECK(called);
+  }
+  {
+    int result = 0;
+    auto fn = asio::spawn(ctx, int_returning_coroutine, asio::deferred);
+
+    fn([&](std::exception_ptr, int i)
+        {
+          result = i;
+        });
+
+    ASIO_CHECK(result == 0);
+
+    ctx.restart();
+    ctx.poll();
+
+    ASIO_CHECK(ctx.stopped());
+    ASIO_CHECK(result == 42);
+  }
+}
+
+void sleeping_coroutine(asio::yield_context yield)
+{
+  asio::steady_timer timer(yield.get_executor(),
+      asio::steady_timer::time_point::max());
+  timer.async_wait(yield);
+}
+
+void test_spawn_cancel()
+{
+  asio::cancellation_signal sig;
+  asio::io_context ctx;
+
+  std::exception_ptr result = nullptr;
+  bool called = false;
+  asio::spawn(ctx, sleeping_coroutine,
+      asio::bind_cancellation_slot(sig.slot(),
+        [&](std::exception_ptr e)
+        {
+          result = e;
+          called = true;
+        }));
+
+  ctx.poll();
+  ASIO_CHECK(!ctx.stopped());
+
+  ASIO_CHECK(!called);
+  ASIO_CHECK(result == nullptr);
+
+  sig.emit(asio::cancellation_type::all);
+
+  ctx.poll();
+  ASIO_CHECK(ctx.stopped());
+
+  ASIO_CHECK(called);
+  ASIO_CHECK(result != nullptr);
+  try
+  {
+    std::rethrow_exception(result);
+  }
+  catch (const std::system_error& e)
+  {
+    ASIO_CHECK(e.code() == asio::error::operation_aborted);
+  }
+  catch (...)
+  {
+    ASIO_ERROR("expected system_error");
+  }
+}
+
+void throwing_coroutine(asio::yield_context)
+{
+  throw std::runtime_error("oops");
+}
+
+void test_spawn_exception()
+{
+  asio::io_context ctx;
+
+  std::exception_ptr result = nullptr;
+  bool called = false;
+  asio::spawn(ctx, throwing_coroutine,
+      [&](std::exception_ptr e)
+      {
+        result = e;
+        called = true;
+      });
+
+  ctx.poll();
+  ASIO_CHECK(ctx.stopped());
+
+  ASIO_CHECK(called);
+  ASIO_CHECK(result != nullptr);
+  try
+  {
+    std::rethrow_exception(result);
+  }
+  catch (const std::runtime_error&)
+  {
+    // ok
+  }
+  catch (...)
+  {
+    ASIO_ERROR("expected runtime_error");
+  }
+}
+
+std::unique_ptr<int> factory_coroutine(asio::yield_context)
+{
+  return std::make_unique<int>(42);
+}
+
+void test_spawn_return_moveonly()
+{
+  asio::io_context ctx;
+
+  std::unique_ptr<int> result;
+  bool called = false;
+  asio::spawn(ctx, factory_coroutine,
+      [&](std::exception_ptr, std::unique_ptr<int> r)
+      {
+        result = std::move(r);
+        called = true;
+      });
+
+  ctx.poll();
+  ASIO_CHECK(ctx.stopped());
+
+  ASIO_CHECK(called);
+  ASIO_CHECK(result);
+  ASIO_CHECK(*result == 42);
+}
+
+ASIO_TEST_SUITE
+(
+  "spawn",
+  ASIO_TEST_CASE(test_spawn_with_any_completion_handler)
+  ASIO_TEST_CASE(test_spawn_deferred)
+  ASIO_TEST_CASE(test_spawn_cancel)
+  ASIO_TEST_CASE(test_spawn_exception)
+  ASIO_TEST_CASE(test_spawn_return_moveonly)
+)