js: fix async macros on windows (#20903)

src/ast/Macro.zig

@@ -118,6 +118,7 @@ pub const MacroContext = struct {
         }
         macro.vm.enableMacroMode();
         defer macro.vm.disableMacroMode();
+        macro.vm.eventLoop().ensureWaker();
 
         const Wrapper = struct {
             args: std.meta.ArgsTuple(@TypeOf(Macro.Runner.run)),
@@ -193,6 +194,7 @@ pub fn init(
     };
 
     vm.enableMacroMode();
+    vm.eventLoop().ensureWaker();
 
     const loaded_result = try vm.loadMacroEntryPoint(input_specifier, function_name, specifier, hash);
 

src/bun.js/event_loop.zig

@@ -314,7 +314,7 @@ pub fn tickConcurrentWithCount(this: *EventLoop) usize {
     return this.tasks.count - start_count;
 }
 
-pub inline fn usocketsLoop(this: *const EventLoop) *uws.Loop {
+pub fn usocketsLoop(this: *const EventLoop) *uws.Loop {
     if (comptime Environment.isWindows) {
         return this.uws_loop.?;
     }
@@ -553,6 +553,11 @@ pub fn ensureWaker(this: *EventLoop) void {
         // _ = actual.addPostHandler(*JSC.EventLoop, this, JSC.EventLoop.afterUSocketsTick);
         // _ = actual.addPreHandler(*JSC.VM, this.virtual_machine.jsc, JSC.VM.drainMicrotasks);
     }
+    if (comptime Environment.isWindows) {
+        if (this.uws_loop == null) {
+            this.uws_loop = bun.uws.Loop.get();
+        }
+    }
     bun.uws.Loop.get().internal_loop_data.setParentEventLoop(bun.JSC.EventLoopHandle.init(this));
 }
 

test/bundler/transpiler/macro-test.test.ts

@@ -8,6 +8,7 @@ import defaultMacro, {
   identity,
   identity as identity1,
   identity as identity2,
+  ireturnapromise,
 } from "./macro.ts" assert { type: "macro" };
 
 import * as macros from "./macro.ts" assert { type: "macro" };
@@ -124,3 +125,7 @@ test("namespace import", () => {
 // test("template string latin1", () => {
 //   expect(identity(`©${""}`)).toBe("©");
 // });
+
+test("ireturnapromise", async () => {
+  expect(await ireturnapromise()).toEqual("aaa");
+});

test/bundler/transpiler/macro.ts

@@ -17,3 +17,9 @@ export function addStringsUTF16(arg: string) {
 export default function() {
   return "defaultdefaultdefault";
 }
+
+export async function ireturnapromise() {
+  const { promise, resolve } = Promise.withResolvers();
+  setTimeout(() => resolve("aaa"), 100);
+  return promise;
+}