feat: Add v8::Isolate::request_garbage_collection_for_testing (#1148)

src/binding.cc

@@ -317,6 +317,11 @@ bool v8__Isolate__HasPendingBackgroundTasks(v8::Isolate* isolate) {
   return isolate->HasPendingBackgroundTasks();
 }
 
+void v8__Isolate__RequestGarbageCollectionForTesting(
+  v8::Isolate* isolate, v8::Isolate::GarbageCollectionType type) {
+  isolate->RequestGarbageCollectionForTesting(type);
+}
+
 void v8__Isolate__CreateParams__CONSTRUCT(
     uninit_t<v8::Isolate::CreateParams>* buf) {
   construct_in_place<v8::Isolate::CreateParams>(buf);

src/isolate.rs

@@ -107,6 +107,15 @@ pub enum PromiseHookType {
   After,
 }
 
+/// Types of garbage collections that can be requested via
+/// [`Isolate::request_garbage_collection_for_testing`].
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[repr(C)]
+pub enum GarbageCollectionType {
+  Full,
+  Minor,
+}
+
 pub type MessageCallback = extern "C" fn(Local<Message>, Local<Value>);
 
 pub type PromiseHook =
@@ -471,6 +480,10 @@ extern "C" {
     callback: extern "C" fn(*const FunctionCallbackInfo),
   );
   fn v8__Isolate__HasPendingBackgroundTasks(isolate: *const Isolate) -> bool;
+  fn v8__Isolate__RequestGarbageCollectionForTesting(
+    isolate: *mut Isolate,
+    r#type: usize,
+  );
 
   fn v8__HeapProfiler__TakeHeapSnapshot(
     isolate: *mut Isolate,
@@ -1140,6 +1153,31 @@ impl Isolate {
     unsafe { v8__Isolate__HasPendingBackgroundTasks(self) }
   }
 
+  /// Request garbage collection with a specific embedderstack state in this
+  /// Isolate. It is only valid to call this function if --expose_gc was
+  /// specified.
+  ///
+  /// This should only be used for testing purposes and not to enforce a garbage
+  /// collection schedule. It has strong negative impact on the garbage
+  /// collection performance. Use IdleNotificationDeadline() or
+  /// LowMemoryNotification() instead to influence the garbage collection
+  /// schedule.
+  #[inline(always)]
+  pub fn request_garbage_collection_for_testing(
+    &mut self,
+    r#type: GarbageCollectionType,
+  ) {
+    unsafe {
+      v8__Isolate__RequestGarbageCollectionForTesting(
+        self,
+        match r#type {
+          GarbageCollectionType::Full => 0,
+          GarbageCollectionType::Minor => 1,
+        },
+      )
+    }
+  }
+
   unsafe fn clear_scope_and_annex(&mut self) {
     // Drop the scope stack.
     ScopeData::drop_root(self);

src/lib.rs

@@ -97,6 +97,7 @@ pub use handle::Global;
 pub use handle::Handle;
 pub use handle::Local;
 pub use handle::Weak;
+pub use isolate::GarbageCollectionType;
 pub use isolate::HeapStatistics;
 pub use isolate::HostCreateShadowRealmContextCallback;
 pub use isolate::HostImportModuleDynamicallyCallback;

tests/test_api.rs

@@ -161,8 +161,7 @@ fn global_from_into_raw() {
     (raw, weak)
   };
 
-  // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-  eval(scope, "gc()").unwrap();
+  scope.request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
   assert!(!weak.is_empty());
 
   {
@@ -172,8 +171,7 @@ fn global_from_into_raw() {
     assert_eq!(global_from_weak, reconstructed);
   }
 
-  // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-  eval(scope, "gc()").unwrap();
+  scope.request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
   assert!(weak.is_empty());
 }
 
@@ -6379,23 +6377,24 @@ fn clear_kept_objects() {
   let context = v8::Context::new(scope);
   let scope = &mut v8::ContextScope::new(scope, context);
 
-  // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
   let step1 = r#"
     var weakrefs = [];
     for (let i = 0; i < 424242; i++) weakrefs.push(new WeakRef({ i }));
-    gc();
+  "#;
+  let step2 = r#"
     if (weakrefs.some(w => !w.deref())) throw "fail";
   "#;
 
-  // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-  let step2 = r#"
-    gc();
+  let step3 = r#"
     if (weakrefs.every(w => w.deref())) throw "fail";
   "#;
 
   eval(scope, step1).unwrap();
-  scope.clear_kept_objects();
+  scope.request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
   eval(scope, step2).unwrap();
+  scope.clear_kept_objects();
+  scope.request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
+  eval(scope, step3).unwrap();
 }
 
 #[test]
@@ -7420,8 +7419,7 @@ fn weak_handle() {
 
   let scope = &mut v8::HandleScope::new(scope);
 
-  // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-  eval(scope, "gc()").unwrap();
+  scope.request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
 
   assert!(weak.is_empty());
   assert_eq!(weak.to_local(scope), None);
@@ -7450,8 +7448,8 @@ fn finalizers() {
     }
 
     let scope = &mut v8::HandleScope::new(scope);
-    // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-    eval(scope, "gc()").unwrap();
+    scope
+      .request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
   }
 
   let finalizer_called = Rc::new(Cell::new(false));
@@ -7486,8 +7484,7 @@ fn finalizers() {
   };
 
   let scope = &mut v8::HandleScope::new(scope);
-  // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-  eval(scope, "gc()").unwrap();
+  scope.request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
   assert!(weak.is_empty());
   assert!(finalizer_called.get());
 }
@@ -7521,8 +7518,8 @@ fn guaranteed_finalizers() {
     }
 
     let scope = &mut v8::HandleScope::new(scope);
-    // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-    eval(scope, "gc()").unwrap();
+    scope
+      .request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
   }
 
   let finalizer_called = Rc::new(Cell::new(false));
@@ -7557,8 +7554,7 @@ fn guaranteed_finalizers() {
   };
 
   let scope = &mut v8::HandleScope::new(scope);
-  // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-  eval(scope, "gc()").unwrap();
+  scope.request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
   assert!(weak.is_empty());
   assert!(finalizer_called.get());
 }
@@ -7583,8 +7579,7 @@ fn weak_from_global() {
   assert_eq!(weak.to_global(scope).unwrap(), global);
 
   drop(global);
-  // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-  eval(scope, "gc()").unwrap();
+  scope.request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
   assert!(weak.is_empty());
 }
 
@@ -7633,8 +7628,8 @@ fn weak_from_into_raw() {
       assert!(!finalizer_called.get());
       (weak1, weak2)
     };
-    // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-    eval(scope, "gc()").unwrap();
+    scope
+      .request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
     assert!(weak1.is_empty());
     assert!(weak2.is_empty());
     assert!(finalizer_called.get());
@@ -7648,8 +7643,8 @@ fn weak_from_into_raw() {
       v8::Weak::new(scope, local)
     };
     assert!(!weak.is_empty());
-    // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-    eval(scope, "gc()").unwrap();
+    scope
+      .request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
     assert!(weak.is_empty());
     assert_eq!(weak.into_raw(), None);
   }
@@ -7680,8 +7675,8 @@ fn weak_from_into_raw() {
     let raw2 = weak_with_finalizer.into_raw();
     assert!(raw1.is_some());
     assert!(raw2.is_some());
-    // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-    eval(scope, "gc()").unwrap();
+    scope
+      .request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
     assert!(finalizer_called.get());
     let weak1 = unsafe { v8::Weak::from_raw(scope, raw1) };
     let weak2 = unsafe { v8::Weak::from_raw(scope, raw2) };
@@ -7695,11 +7690,10 @@ fn weak_from_into_raw() {
     let local = v8::Object::new(scope);
     v8::Weak::new(scope, local).into_raw();
     v8::Weak::with_finalizer(scope, local, Box::new(|_| {})).into_raw();
-    // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-    eval(scope, "gc()").unwrap();
+    scope
+      .request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
   }
-  // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-  eval(scope, "gc()").unwrap();
+  scope.request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
 }
 
 #[test]
@@ -7739,8 +7733,7 @@ fn drop_weak_from_raw_in_finalizer() {
   }
 
   assert!(!finalized.get());
-  // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-  eval(scope, "gc()").unwrap();
+  scope.request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
   assert!(finalized.get());
 }
 
@@ -8747,8 +8740,8 @@ fn gc_callbacks() {
     let context = v8::Context::new(scope);
     let scope = &mut v8::ContextScope::new(scope, context);
 
-    // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-    eval(scope, "gc()").unwrap();
+    scope
+      .request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
     assert_eq!(state.mark_sweep_calls, 1);
     assert_eq!(state.incremental_marking_calls, 0);
   }
@@ -8760,8 +8753,8 @@ fn gc_callbacks() {
     let context = v8::Context::new(scope);
     let scope = &mut v8::ContextScope::new(scope, context);
 
-    // TODO use binding to Isolate::RequestGarbageCollectionForTesting instead of gc()
-    eval(scope, "gc()").unwrap();
+    scope
+      .request_garbage_collection_for_testing(v8::GarbageCollectionType::Full);
     // Assert callback was removed and not called again.
     assert_eq!(state.mark_sweep_calls, 1);
     assert_eq!(state.incremental_marking_calls, 0);