Perform a microtask checkpoint after executing classic scripts and callbacks.

components/script/dom/bindings/settings_stack.rs

@@ -11,6 +11,7 @@ use js::jsapi::JSTracer;
 use js::jsapi::UnhideScriptedCaller;
 use js::rust::Runtime;
 use std::cell::RefCell;
+use std::thread;
 
 thread_local!(static STACK: RefCell<Vec<StackEntry>> = RefCell::new(Vec::new()));
 
@@ -36,7 +37,7 @@ pub unsafe fn trace(tracer: *mut JSTracer) {
 
 /// RAII struct that pushes and pops entries from the script settings stack.
 pub struct AutoEntryScript {
-    global: usize,
+    global: Root<GlobalScope>,
 }
 
 impl AutoEntryScript {
@@ -50,7 +51,7 @@ impl AutoEntryScript {
                 kind: StackEntryKind::Entry,
             });
             AutoEntryScript {
-                global: global as *const _ as usize,
+                global: Root::from_ref(global),
             }
         })
     }
@@ -62,12 +63,17 @@ impl Drop for AutoEntryScript {
         STACK.with(|stack| {
             let mut stack = stack.borrow_mut();
             let entry = stack.pop().unwrap();
-            assert_eq!(&*entry.global as *const GlobalScope as usize,
+            assert_eq!(&*entry.global as *const GlobalScope,
-                       self.global,
+                       &*self.global as *const GlobalScope,
                        "Dropped AutoEntryScript out of order.");
             assert_eq!(entry.kind, StackEntryKind::Entry);
             trace!("Clean up after running script with {:p}", &*entry.global);
-        })
+        });
+
+        // Step 5
+        if !thread::panicking() && incumbent_global().is_none() {
+            self.global.perform_a_microtask_checkpoint();
+        }
     }
 }
 

components/script/dom/globalscope.rs

@@ -449,6 +449,17 @@ impl GlobalScope {
         unreachable!();
     }
 
+    /// Perform a microtask checkpoint.
+    pub fn perform_a_microtask_checkpoint(&self) {
+        if self.is::<Window>() {
+            return ScriptThread::invoke_perform_a_microtask_checkpoint();
+        }
+        if let Some(worker) = self.downcast::<WorkerGlobalScope>() {
+            return worker.perform_a_microtask_checkpoint();
+        }
+        unreachable!();
+    }
+
     /// Enqueue a microtask for subsequent execution.
     pub fn enqueue_microtask(&self, job: Microtask) {
         if self.is::<Window>() {

components/script/dom/htmlscriptelement.rs

@@ -486,11 +486,7 @@ impl HTMLScriptElement {
         document.set_current_script(Some(self));
 
         // Step 5.a.2.
-        let window = window_from_node(self);
+        self.run_a_classic_script(&script);
-        let line_number = if script.external { 1 } else { self.line_number as u32 };
-        rooted!(in(window.get_cx()) let mut rval = UndefinedValue());
-        window.upcast::<GlobalScope>().evaluate_script_on_global_with_result(
-            &script.text, script.url.as_str(), rval.handle_mut(), line_number);
 
         // Step 6.
         document.set_current_script(old_script.r());
@@ -506,6 +502,24 @@ impl HTMLScriptElement {
         }
     }
 
+    // https://html.spec.whatwg.org/multipage/#run-a-classic-script
+    pub fn run_a_classic_script(&self, script: &ClassicScript) {
+        // TODO use a settings object rather than this element's document/window
+        // Step 2
+        let document = document_from_node(self);
+        if !document.is_fully_active() || !document.is_scripting_enabled() {
+            return;
+        }
+
+        // Steps 4-10
+        let window = window_from_node(self);
+        let line_number = if script.external { 1 } else { self.line_number as u32 };
+        rooted!(in(window.get_cx()) let mut rval = UndefinedValue());
+        let global = window.upcast::<GlobalScope>();
+        global.evaluate_script_on_global_with_result(
+            &script.text, script.url.as_str(), rval.handle_mut(), line_number);
+    }
+
     pub fn queue_error_event(&self) {
         let window = window_from_node(self);
         window.dom_manipulation_task_source().queue_simple_event(self.upcast(), atom!("error"), &window);

components/script/script_thread.rs

@@ -567,6 +567,13 @@ impl ScriptThreadFactory for ScriptThread {
 }
 
 impl ScriptThread {
+    pub fn invoke_perform_a_microtask_checkpoint() {
+        SCRIPT_THREAD_ROOT.with(|root| {
+            let script_thread = unsafe { &*root.get().unwrap() };
+            script_thread.perform_a_microtask_checkpoint()
+        })
+    }
+
     pub fn page_headers_available(id: &PipelineId, metadata: Option<Metadata>)
                                   -> Option<Root<ServoParser>> {
         SCRIPT_THREAD_ROOT.with(|root| {

tests/wpt/metadata/html/webappapis/scripting/event-loops/microtask_after_raf.html.ini

@@ -1,6 +0,0 @@
-[microtask_after_raf.html]
-  type: testharness
-  disabled: https://github.com/servo/servo/issues/13501
-  [Microtask execute immediately after script]
-    expected: FAIL
-

tests/wpt/metadata/html/webappapis/scripting/event-loops/microtask_after_script.html.ini

@@ -1,5 +0,0 @@
-[microtask_after_script.html]
-  type: testharness
-  [Microtask immediately after script]
-    expected: FAIL
-

tests/wpt/metadata/html/webappapis/scripting/event-loops/task_microtask_ordering.html.ini

@@ -1,8 +1,5 @@
 [task_microtask_ordering.html]
   type: testharness
-  [Basic task and microtask ordering]
-    expected: FAIL
-
   [Level 1 bossfight (synthetic click)]
     expected: FAIL
-
+    bug: https://github.com/servo/servo/issues/1980