fix: make sure Bun.sleep(Date) doesn't resolve prematurely (#8950)

* fix: make sure Bun.sleep(Date) doesn't return prematurely

Fixes #8834.

This makes Bun.sleep(new Date(x)) fulfill its promise only when
Date.now() >= x.

* resolve test now #8834 is fixed

11 ms is in fact the right limit.

---------

Co-authored-by: John-David Dalton <john.david.dalton@gmail.com>

src/bun.js/bindings/BunObject.cpp

@@ -352,8 +352,8 @@ JSC_DEFINE_HOST_FUNCTION(functionBunSleep,
 
     if (millisecondsValue.inherits<JSC::DateInstance>()) {
         auto now = MonotonicTime::now();
-        auto milliseconds = jsCast<JSC::DateInstance*>(millisecondsValue)->internalNumber() - now.approximateWallTime().secondsSinceEpoch().milliseconds();
-        millisecondsValue = JSC::jsNumber(milliseconds > 0 ? milliseconds : 0);
+        double milliseconds = jsCast<JSC::DateInstance*>(millisecondsValue)->internalNumber() - now.approximateWallTime().secondsSinceEpoch().milliseconds();
+        millisecondsValue = JSC::jsNumber(milliseconds > 0 ? std::ceil(milliseconds) : 0);
     }
 
     if (!millisecondsValue.isNumber()) {

test/js/web/timers/setTimeout.test.js

@@ -152,9 +152,15 @@ it("Bun.sleep works with a Date object", async () => {
   var ten_ms = new Date();
   ten_ms.setMilliseconds(ten_ms.getMilliseconds() + 12);
   await Bun.sleep(ten_ms);
-  // TODO: Fix https://github.com/oven-sh/bun/issues/8834
-  // This should be .toBeGreaterThan(11), or maybe even 12
-  expect(performance.now() - now).toBeGreaterThan(10);
+  expect(performance.now() - now).toBeGreaterThan(11);
+});
+
+it("Bun.sleep(Date) fulfills after Date", async () => {
+  let ten_ms = new Date();
+  ten_ms.setMilliseconds(ten_ms.getMilliseconds() + 12);
+  await Bun.sleep(ten_ms);
+  let now = new Date();
+  expect(+now).toBeGreaterThanOrEqual(+ten_ms);
 });
 
 it("node.js timers/promises setTimeout propagates exceptions", async () => {