1 files changed, 107 insertions, 0 deletions
diff --git a/src/bun.js/bindings/AsyncContextFrame.cpp b/src/bun.js/bindings/AsyncContextFrame.cpp
new file mode 100644
index 000000000..326350664
--- /dev/null
+++ b/src/bun.js/bindings/AsyncContextFrame.cpp
@@ -0,0 +1,107 @@
+#pragma once
+
+#include "root.h"
+#include "ZigGlobalObject.h"
+#include "AsyncContextFrame.h"
+#include "JavaScriptCore/InternalFieldTuple.h"
+
+using namespace JSC;
+using namespace WebCore;
+
+const ClassInfo AsyncContextFrame::s_info = { "AsyncContextFrame"_s, &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(AsyncContextFrame) };
+
+AsyncContextFrame* AsyncContextFrame::create(VM& vm, JSC::Structure* structure, JSValue callback, JSValue context)
+{
+    AsyncContextFrame* asyncContextData = new (NotNull, allocateCell<AsyncContextFrame>(vm)) AsyncContextFrame(vm, structure);
+    asyncContextData->finishCreation(vm);
+    asyncContextData->callback.set(vm, asyncContextData, callback);
+    asyncContextData->context.set(vm, asyncContextData, context);
+    return asyncContextData;
+}
+
+AsyncContextFrame* AsyncContextFrame::create(JSGlobalObject* global, JSValue callback, JSValue context)
+{
+    auto& vm = global->vm();
+    AsyncContextFrame* asyncContextData = new (NotNull, allocateCell<AsyncContextFrame>(vm)) AsyncContextFrame(vm, static_cast<Zig::GlobalObject*>(global)->AsyncContextFrameStructure());
+    asyncContextData->finishCreation(vm);
+    asyncContextData->callback.set(vm, asyncContextData, callback);
+    asyncContextData->context.set(vm, asyncContextData, context);
+    return asyncContextData;
+}
+
+JSC::Structure* AsyncContextFrame::createStructure(JSC::VM& vm, JSC::JSGlobalObject* globalObject)
+{
+    return Structure::create(vm, globalObject, jsNull(), TypeInfo(ObjectType, StructureFlags), info());
+}
+
+JSValue AsyncContextFrame::withAsyncContextIfNeeded(JSGlobalObject* globalObject, JSValue callback)
+{
+    JSValue context = globalObject->m_asyncContextData.get()->getInternalField(0);
+
+    // If there is no async context, do not snapshot the callback.
+    if (context.isUndefined()) {
+        return callback;
+    }
+
+    // Construct a low-overhead wrapper
+    auto& vm = globalObject->vm();
+    return AsyncContextFrame::create(
+        vm,
+        static_cast<Zig::GlobalObject*>(globalObject)->AsyncContextFrameStructure(),
+        callback,
+        context);
+}
+
+template<typename Visitor>
+void AsyncContextFrame::visitChildrenImpl(JSCell* cell, Visitor& visitor)
+{
+    auto* thisObject = jsCast<AsyncContextFrame*>(cell);
+    ASSERT_GC_OBJECT_INHERITS(thisObject, info());
+    Base::visitChildren(thisObject, visitor);
+    visitor.append(thisObject->callback);
+    visitor.append(thisObject->context);
+}
+
+DEFINE_VISIT_CHILDREN(AsyncContextFrame);
+
+extern "C" EncodedJSValue AsyncContextFrame__withAsyncContextIfNeeded(JSGlobalObject* globalObject, EncodedJSValue callback)
+{
+    return JSValue::encode(AsyncContextFrame::withAsyncContextIfNeeded(globalObject, JSValue::decode(callback)));
+}
+
+#define ASYNCCONTEXTFRAME_CALL_IMPL(...)                                     \
+    if (!functionObject.isCell())                                            \
+        return jsUndefined();                                                \
+    auto& vm = global->vm();                                                 \
+    JSValue restoreAsyncContext;                                             \
+    InternalFieldTuple* asyncContextData = nullptr;                          \
+    if (auto* wrapper = jsDynamicCast<AsyncContextFrame*>(functionObject)) { \
+        functionObject = jsCast<JSC::JSObject*>(wrapper->callback.get());    \
+        asyncContextData = global->m_asyncContextData.get();                 \
+        restoreAsyncContext = asyncContextData->getInternalField(0);         \
+        asyncContextData->putInternalField(vm, 0, wrapper->context.get());   \
+    }                                                                        \
+    auto result = JSC::call(__VA_ARGS__);                                    \
+    if (asyncContextData) {                                                  \
+        asyncContextData->putInternalField(vm, 0, restoreAsyncContext);      \
+    }                                                                        \
+    return result;
+
+JSValue AsyncContextFrame::call(JSGlobalObject* global, JSValue functionObject, const ArgList& args, ASCIILiteral errorMessage)
+{
+    ASYNCCONTEXTFRAME_CALL_IMPL(global, functionObject, args, errorMessage);
+}
+JSValue AsyncContextFrame::call(JSGlobalObject* global, JSValue functionObject, JSValue thisValue, const ArgList& args, ASCIILiteral errorMessage)
+{
+    ASYNCCONTEXTFRAME_CALL_IMPL(global, functionObject, thisValue, args, errorMessage);
+}
+JSValue AsyncContextFrame::call(JSGlobalObject* global, JSValue functionObject, JSValue thisValue, const ArgList& args)
+{
+    ASYNCCONTEXTFRAME_CALL_IMPL(global, functionObject, JSC::getCallData(functionObject), thisValue, args);
+}
+JSValue AsyncContextFrame::call(JSGlobalObject* global, JSValue functionObject, JSValue thisValue, const ArgList& args, NakedPtr<Exception>& returnedException)
+{
+    ASYNCCONTEXTFRAME_CALL_IMPL(global, functionObject, JSC::getCallData(functionObject), thisValue, args, returnedException);
+}
+
+#undef ASYNCCONTEXTFRAME_CALL_IMPL