LibWeb: Implement AbortSignal.any()

This method takes a list of AbortSignals and returns an AbortSignal
that is aborted when any of the input signals is aborted.

Tests/LibWeb/Text/expected/abortsignal-any.txt

@@ -0,0 +1,39 @@
+Signal 0 aborted: false
+Signal 1 aborted: false
+Signal 2 aborted: false
+Signal 3 aborted: false
+Signal 4 aborted: false
+Abort callback for signal: 0. Reason: Test AbortController 1
+Abort callback for signal: 1. Reason: Test AbortController 1
+Abort callback for signal: 3. Reason: Test AbortController 1
+Abort callback for signal: 4. Reason: Test AbortController 1
+Signal 0 aborted: true
+Signal 1 aborted: true
+Signal 2 aborted: false
+Signal 3 aborted: true
+Signal 4 aborted: true
+Signal 0 aborted: false
+Signal 1 aborted: false
+Signal 2 aborted: false
+Signal 3 aborted: false
+Signal 4 aborted: false
+Abort callback for signal: 1. Reason: Test AbortController 2
+Abort callback for signal: 2. Reason: Test AbortController 2
+Abort callback for signal: 3. Reason: Test AbortController 2
+Abort callback for signal: 4. Reason: Test AbortController 2
+Signal 0 aborted: false
+Signal 1 aborted: true
+Signal 2 aborted: true
+Signal 3 aborted: true
+Signal 4 aborted: true
+Signal 0 aborted: false
+Signal 1 aborted: false
+Signal 2 aborted: false
+Signal 3 aborted: false
+Signal 4 aborted: false
+Abort callback for signal: 4. Reason: Test AbortController 3
+Signal 0 aborted: false
+Signal 1 aborted: false
+Signal 2 aborted: false
+Signal 3 aborted: false
+Signal 4 aborted: true

Tests/LibWeb/Text/input/abortsignal-any.html

@@ -0,0 +1,52 @@
+<script src="include.js"></script>
+<script>
+    test(() => {
+        function make_callback(signal, signal_number) {
+            return () => println(`Abort callback for signal: ${signal_number}. Reason: ${signal.reason}`);
+        }
+
+        function make_signal_list() {
+            const controller1 = new AbortController();
+            const controller2 = new AbortController();
+            const controller3 = new AbortController();
+
+            let signals = [];
+            signals.push(AbortSignal.any([controller1.signal]));
+            signals.push(AbortSignal.any([controller1.signal, controller2.signal]));
+            signals.push(AbortSignal.any([controller2.signal]));
+            signals.push(AbortSignal.any([controller2.signal, controller1.signal]));
+
+            const nestedSignal = AbortSignal.any([...signals, controller3.signal]);
+            signals.push(nestedSignal);
+
+            for (let i = 0; i < signals.length; i++) {
+                const signal = signals[i];
+                signal.onabort = make_callback(signal, i);
+            }
+
+            return { controllers: [controller1, controller2, controller3], signals: signals};
+        }
+
+        function print_aborted_signals(signals) {
+            for (let i = 0; i < signals.length; i++) {
+                const signal = signals[i];
+                println(`Signal ${i} aborted: ${signal.aborted}`);
+            }
+        }
+
+        const signal_list1 = make_signal_list();
+        print_aborted_signals(signal_list1.signals);
+        signal_list1.controllers[0].abort("Test AbortController 1");
+        print_aborted_signals(signal_list1.signals);
+
+        const signal_list2 = make_signal_list();
+        print_aborted_signals(signal_list2.signals);
+        signal_list2.controllers[1].abort("Test AbortController 2");
+        print_aborted_signals(signal_list2.signals);
+
+        const signal_list3 = make_signal_list();
+        print_aborted_signals(signal_list3.signals);
+        signal_list3.controllers[2].abort("Test AbortController 3");
+        print_aborted_signals(signal_list3.signals);
+    });
+</script>

Userland/Libraries/LibWeb/DOM/AbortSignal.cpp

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2021, Luke Wilde <lukew@serenityos.org>
+ * Copyright (c) 2024, Tim Ledbetter <timledbetter@gmail.com>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -67,6 +68,10 @@ void AbortSignal::signal_abort(JS::Value reason)
     auto abort_event = Event::create(realm(), HTML::EventNames::abort);
     abort_event->set_is_trusted(true);
     dispatch_event(abort_event);
+
+    // 6. For each dependentSignal of signal’s dependent signals, signal abort on dependentSignal with signal’s abort reason.
+    for (auto const& dependent_signal : m_dependent_signals)
+        dependent_signal->signal_abort(reason);
 }
 
 void AbortSignal::set_onabort(WebIDL::CallbackType* event_handler)
@@ -95,6 +100,12 @@ void AbortSignal::visit_edges(JS::Cell::Visitor& visitor)
     visitor.visit(m_abort_reason);
     for (auto& algorithm : m_abort_algorithms)
         visitor.visit(algorithm);
+
+    for (auto& source_signal : m_source_signals)
+        visitor.visit(source_signal);
+
+    for (auto& dependent_signal : m_dependent_signals)
+        visitor.visit(dependent_signal);
 }
 
 // https://dom.spec.whatwg.org/#abortsignal-follow
@@ -162,4 +173,74 @@ WebIDL::ExceptionOr<JS::NonnullGCPtr<AbortSignal>> AbortSignal::timeout(JS::VM&
     return signal;
 }
 
+// https://dom.spec.whatwg.org/#dom-abortsignal-any
+WebIDL::ExceptionOr<JS::NonnullGCPtr<AbortSignal>> AbortSignal::any(JS::VM& vm, JS::Value signals)
+{
+    Vector<JS::Handle<AbortSignal>> signals_list;
+    auto iterator_record = TRY(get_iterator(vm, signals, JS::IteratorHint::Sync));
+    while (true) {
+        auto next = TRY(iterator_step_value(vm, iterator_record));
+        if (!next.has_value())
+            break;
+
+        auto value = next.release_value();
+        if (!value.is_object() || !is<AbortSignal>(value.as_object()))
+            return vm.throw_completion<JS::TypeError>(JS::ErrorType::NotAnObjectOfType, "AbortSignal");
+
+        auto& signal = static_cast<AbortSignal&>(value.as_object());
+        signals_list.append(JS::make_handle(signal));
+    }
+
+    // The static any(signals) method steps are to return the result of creating a dependent abort signal from signals using AbortSignal and the current realm.
+    return create_dependent_abort_signal(*vm.current_realm(), signals_list);
+}
+
+// https://dom.spec.whatwg.org/#create-a-dependent-abort-signal
+WebIDL::ExceptionOr<JS::NonnullGCPtr<AbortSignal>> AbortSignal::create_dependent_abort_signal(JS::Realm& realm, Vector<JS::Handle<AbortSignal>> const& signals)
+{
+    // 1. Let resultSignal be a new object implementing signalInterface using realm.
+    auto result_signal = TRY(construct_impl(realm));
+
+    // 2. For each signal of signals: if signal is aborted, then set resultSignal’s abort reason to signal’s abort reason and return resultSignal.
+    for (auto const& signal : signals) {
+        if (signal->aborted()) {
+            result_signal->set_reason(signal->reason());
+            return result_signal;
+        }
+    }
+
+    // 3. Set resultSignal’s dependent to true.
+    result_signal->set_dependent(true);
+
+    // 4. For each signal of signals:
+    for (auto const& signal : signals) {
+        // 1. If signal’s dependent is false, then:
+        if (!signal->dependent()) {
+            // 1. Append signal to resultSignal’s source signals.
+            result_signal->append_source_signal({ signal });
+
+            // 2. Append resultSignal to signal’s dependent signals.
+            signal->append_dependent_signal(result_signal);
+        }
+        // 2. Otherwise, for each sourceSignal of signal’s source signals:
+        else {
+            for (auto const& source_signal : signal->source_signals()) {
+                // 1. Assert: sourceSignal is not aborted and not dependent.
+                VERIFY(source_signal);
+                VERIFY(!source_signal->aborted());
+                VERIFY(!source_signal->dependent());
+
+                // 2. Append sourceSignal to resultSignal’s source signals.
+                result_signal->append_source_signal(source_signal);
+
+                // 3. Append resultSignal to sourceSignal’s dependent signals.
+                source_signal->append_dependent_signal(result_signal);
+            }
+        }
+    }
+
+    // 5. Return resultSignal
+    return result_signal;
+}
+
 }

Userland/Libraries/LibWeb/DOM/AbortSignal.h

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2021, Luke Wilde <lukew@serenityos.org>
+ * Copyright (c) 2024, Tim Ledbetter <timledbetter@gmail.com>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -46,6 +47,7 @@ public:
 
     static WebIDL::ExceptionOr<JS::NonnullGCPtr<AbortSignal>> abort(JS::VM&, JS::Value reason);
     static WebIDL::ExceptionOr<JS::NonnullGCPtr<AbortSignal>> timeout(JS::VM&, Web::WebIDL::UnsignedLongLong milliseconds);
+    static WebIDL::ExceptionOr<JS::NonnullGCPtr<AbortSignal>> any(JS::VM&, JS::Value signals);
 
 private:
     explicit AbortSignal(JS::Realm&);
@@ -53,6 +55,16 @@ private:
     virtual void initialize(JS::Realm&) override;
     virtual void visit_edges(JS::Cell::Visitor&) override;
 
+    static WebIDL::ExceptionOr<JS::NonnullGCPtr<AbortSignal>> create_dependent_abort_signal(JS::Realm&, Vector<JS::Handle<AbortSignal>> const&);
+
+    bool dependent() const { return m_dependent; }
+    void set_dependent(bool dependent) { m_dependent = dependent; }
+
+    Vector<JS::GCPtr<AbortSignal>> source_signals() const { return m_source_signals; }
+
+    void append_source_signal(JS::GCPtr<AbortSignal> source_signal) { m_source_signals.append(source_signal); }
+    void append_dependent_signal(JS::GCPtr<AbortSignal> dependent_signal) { m_dependent_signals.append(dependent_signal); }
+
     // https://dom.spec.whatwg.org/#abortsignal-abort-reason
     // An AbortSignal object has an associated abort reason, which is a JavaScript value. It is undefined unless specified otherwise.
     JS::Value m_abort_reason { JS::js_undefined() };
@@ -60,6 +72,18 @@ private:
     // https://dom.spec.whatwg.org/#abortsignal-abort-algorithms
     // FIXME: This should be a set.
     Vector<JS::NonnullGCPtr<JS::HeapFunction<void()>>> m_abort_algorithms;
+
+    // https://dom.spec.whatwg.org/#abortsignal-source-signals
+    // An AbortSignal object has associated source signals (a weak set of AbortSignal objects that the object is dependent on for its aborted state), which is initially empty.
+    Vector<JS::GCPtr<AbortSignal>> m_source_signals;
+
+    // https://dom.spec.whatwg.org/#abortsignal-dependent-signals
+    // An AbortSignal object has associated dependent signals (a weak set of AbortSignal objects that are dependent on the object for their aborted state), which is initially empty.
+    Vector<JS::GCPtr<AbortSignal>> m_dependent_signals;
+
+    // https://dom.spec.whatwg.org/#abortsignal-dependent
+    // An AbortSignal object has a dependent (a boolean), which is initially false.
+    bool m_dependent { false };
 };
 
 }

Userland/Libraries/LibWeb/DOM/AbortSignal.idl

@@ -6,7 +6,8 @@
 interface AbortSignal : EventTarget {
     [NewObject] static AbortSignal abort(optional any reason);
     [Exposed=(Window,Worker), NewObject] static AbortSignal timeout([EnforceRange] unsigned long long milliseconds);
-    // FIXME: [NewObject] static AbortSignal _any(sequence<AbortSignal> signals);
+    // FIXME: Argument should be of type: sequence<AbortSignal>.
+    [NewObject] static AbortSignal _any(any signals);
 
     readonly attribute boolean aborted;
     readonly attribute any reason;