From ab196b9adfba511e1880fa78c8fea3b3edbde083 Mon Sep 17 00:00:00 2001
From: matcool <26722564+matcool@users.noreply.github.com>
Date: Tue, 12 Nov 2024 12:21:09 -0300
Subject: [PATCH] allow sending progress from Task coroutines by using co_yield

---
 loader/include/Geode/utils/Task.hpp | 39 ++++++++++++++++++++---------
 1 file changed, 27 insertions(+), 12 deletions(-)

diff --git a/loader/include/Geode/utils/Task.hpp b/loader/include/Geode/utils/Task.hpp
index 6971a2fc..7a40e3e4 100644
--- a/loader/include/Geode/utils/Task.hpp
+++ b/loader/include/Geode/utils/Task.hpp
@@ -9,7 +9,7 @@
 
 namespace geode {
     namespace geode_internal {
-        template <class T>
+        template <class T, class P>
         struct TaskPromise;
 
         template <class T, class P>
@@ -161,7 +161,7 @@ namespace geode {
             template <std::move_constructible T2, std::move_constructible P2>
             friend class Task;
 
-            template <class>
+            template <class, class>
             friend struct geode_internal::TaskPromise;
 
             template <class, class>
@@ -322,7 +322,7 @@ namespace geode {
         template <std::move_constructible T2, std::move_constructible P2>
         friend class Task;
 
-        template <class>
+        template <class, class>
         friend struct geode_internal::TaskPromise;
 
         template <class, class>
@@ -924,12 +924,22 @@ namespace geode {
 //
 // The body of the coroutine is ran in whatever thread it got called in.
 // TODO: maybe guarantee main thread?
+//
+// The coroutine can also yield progress values using `co_yield`:
+// ```
+// Task<std::string, int> someTask() {
+//     for (int i = 0; i < 10; i++) {
+//         co_yield i;
+//     }
+//     co_return "done!";
+// }
+// ```
 
 namespace geode {
     namespace geode_internal {
-        template <class T>
+        template <class T, class P>
         struct TaskPromise {
-            using MyTask = Task<T>;
+            using MyTask = Task<T, P>;
             std::weak_ptr<typename MyTask::Handle> m_handle;
 
             ~TaskPromise() {
@@ -948,10 +958,15 @@ namespace geode {
                 return handle;
             }
 
-            void return_value(T&& x) {
+            void return_value(T x) {
                 MyTask::finish(m_handle.lock(), std::move(x));
             }
 
+            std::suspend_never yield_value(P value) {
+                MyTask::progress(m_handle.lock(), std::move(value));
+                return {};
+            }
+
             bool isCancelled() {
                 if (auto p = m_handle.lock()) {
                     return p->is(MyTask::Status::Cancelled);
@@ -968,8 +983,8 @@ namespace geode {
                 return task.isFinished();
             }
 
-            template <class U>
-            void await_suspend(std::coroutine_handle<TaskPromise<U>> handle) {
+            template <class U, class V>
+            void await_suspend(std::coroutine_handle<TaskPromise<U, V>> handle) {
                 if (handle.promise().isCancelled()) {
                     handle.destroy();
                     return;
@@ -981,7 +996,7 @@ namespace geode {
                     handle.destroy();
                     return;
                 }
-                parentHandle->m_extraData = std::make_unique<typename Task<U>::Handle::ExtraData>(
+                parentHandle->m_extraData = std::make_unique<typename Task<U, V>::Handle::ExtraData>(
                     static_cast<void*>(new EventListener<Task<T, P>>(
                         [handle](auto* event) {
                             if (event->getValue()) {
@@ -1014,7 +1029,7 @@ auto operator co_await(geode::Task<T, P> task) {
     return geode::geode_internal::TaskAwaiter<T, P>{task};
 }
 
-template <class T, class... Args>
-struct std::coroutine_traits<geode::Task<T>, Args...> {
-    using promise_type = geode::geode_internal::TaskPromise<T>;
+template <class T, class P, class... Args>
+struct std::coroutine_traits<geode::Task<T, P>, Args...> {
+    using promise_type = geode::geode_internal::TaskPromise<T, P>;
 };
\ No newline at end of file