fix start delay on Worker (#3707)

* fix start delay on Worker

* fmt

* add delay test

2 files changed, 14 insertions, 2 deletions

diff --git a/src/bun.js/javascript.zig b/src/bun.js/javascript.zig
index a198259ed..94d82c496 100644
--- a/src/bun.js/javascript.zig
+++ b/src/bun.js/javascript.zig
@@ -1869,6 +1869,16 @@ pub const VirtualMachine = struct {
         return promise;
     }
 
+    // worker dont has bun_watcher and also we dont wanna call autoTick before dispatchOnline
+    pub fn loadEntryPointForWebWorker(this: *VirtualMachine, entry_path: string) anyerror!*JSInternalPromise {
+        var promise = try this.reloadEntryPoint(entry_path);
+        this.eventLoop().performGC();
+        this.waitForPromise(JSC.AnyPromise{
+            .Internal = promise,
+        });
+        return this.pending_internal_promise;
+    }
+
     pub fn loadEntryPoint(this: *VirtualMachine, entry_path: string) anyerror!*JSInternalPromise {
         var promise = try this.reloadEntryPoint(entry_path);
 
diff --git a/src/bun.js/web_worker.zig b/src/bun.js/web_worker.zig
index 7bbd73e27..504b0adeb 100644
--- a/src/bun.js/web_worker.zig
+++ b/src/bun.js/web_worker.zig
@@ -266,7 +266,7 @@ pub const WebWorker = struct {
         std.debug.assert(this.status == .start);
         this.setStatus(.starting);
 
-        var promise = vm.loadEntryPoint(this.specifier) catch {
+        var promise = vm.loadEntryPointForWebWorker(this.specifier) catch {
             this.flushLogs();
             this.onTerminate();
             return;
@@ -298,9 +298,11 @@ pub const WebWorker = struct {
             vm.global.vm().releaseWeakRefs();
             _ = vm.arena.gc(false);
             _ = vm.global.vm().runGC(false);
-            vm.tick();
         }
 
+        // always doing a first tick so we call CppTask without delay after dispatchOnline
+        vm.tick();
+
         {
             while (true) {
                 while (vm.eventLoop().tasks.count > 0 or vm.active_tasks > 0 or vm.uws_event_loop.?.active > 0) {