[dom] Implement AbortSignal.any() prototype

dom/abort/abort-signal-any.tentative.any.js

@@ -0,0 +1,4 @@
+// META: script=./resources/abort-signal-any-tests.js
+
+abortSignalAnySignalOnlyTests(AbortSignal);
+abortSignalAnyTests(AbortSignal, AbortController);

dom/abort/resources/abort-signal-any-tests.js

@@ -0,0 +1,185 @@
+// Tests for AbortSignal.any() and subclasses that don't use a controller.
+function abortSignalAnySignalOnlyTests(signalInterface) {
+  const desc = `${signalInterface.name}.any()`
+
+  test(t => {
+    const signal = signalInterface.any([]);
+    assert_false(signal.aborted);
+  }, `${desc} works with an empty array of signals`);
+}
+
+// Tests for AbortSignal.any() and subclasses that use a controller.
+function abortSignalAnyTests(signalInterface, controllerInterface) {
+  const suffix = `(using ${controllerInterface.name})`;
+  const desc = `${signalInterface.name}.any()`;
+
+  test(t => {
+    const controller = new controllerInterface();
+    const signal = controller.signal;
+    const cloneSignal = signalInterface.any([signal]);
+    assert_false(cloneSignal.aborted);
+    assert_true("reason" in cloneSignal, "cloneSignal has reason property");
+    assert_equals(cloneSignal.reason, undefined,
+        "cloneSignal.reason is initially undefined");
+    assert_not_equals(signal, cloneSignal,
+        `${desc} returns a new signal.`);
+
+    let eventFired = false;
+    cloneSignal.onabort = t.step_func((e) => {
+      assert_equals(e.target, cloneSignal,
+          `The event target is the signal returned by ${desc}`);
+      eventFired = true;
+    });
+
+    controller.abort("reason string");
+    assert_true(signal.aborted);
+    assert_true(cloneSignal.aborted);
+    assert_true(eventFired);
+    assert_equals(cloneSignal.reason, "reason string",
+        `${desc} propagates the abort reason`);
+  }, `${desc} follows a single signal ${suffix}`);
+
+  test(t => {
+    for (let i = 0; i < 3; ++i) {
+      const controllers = [];
+      for (let j = 0; j < 3; ++j) {
+        controllers.push(new controllerInterface());
+      }
+      const combinedSignal = signalInterface.any(controllers.map(c => c.signal));
+
+      let eventFired = false;
+      combinedSignal.onabort = t.step_func((e) => {
+        assert_equals(e.target, combinedSignal,
+            `The event target is the signal returned by ${desc}`);
+        eventFired = true;
+      });
+
+      controllers[i].abort();
+      assert_true(eventFired);
+      assert_true(combinedSignal.aborted);
+      assert_true(combinedSignal.reason instanceof DOMException,
+          "signal.reason is a DOMException");
+      assert_equals(combinedSignal.reason.name, "AbortError",
+          "signal.reason is a AbortError");
+    }
+  }, `${desc} follows multiple signals ${suffix}`);
+
+  test(t => {
+    const controllers = [];
+    for (let i = 0; i < 3; ++i) {
+      controllers.push(new controllerInterface());
+    }
+    controllers[1].abort("reason 1");
+    controllers[2].abort("reason 2");
+
+    const signal = signalInterface.any(controllers.map(c => c.signal));
+    assert_true(signal.aborted);
+    assert_equals(signal.reason, "reason 1",
+        "The signal should be aborted with the first reason");
+  }, `${desc} returns an aborted signal if passed an aborted signal ${suffix}`);
+
+  test(t => {
+    const controller = new controllerInterface();
+    const signal = signalInterface.any([controller.signal, controller.signal]);
+    assert_false(signal.aborted);
+    controller.abort("reason");
+    assert_true(signal.aborted);
+    assert_equals(signal.reason, "reason");
+  }, `${desc} can be passed the same signal more than once ${suffix}`);
+
+  test(t => {
+    const controller1 = new controllerInterface();
+    controller1.abort("reason 1");
+    const controller2 = new controllerInterface();
+    controller2.abort("reason 2");
+
+    const signal = signalInterface.any([controller1.signal, controller2.signal, controller1.signal]);
+    assert_true(signal.aborted);
+    assert_equals(signal.reason, "reason 1");
+  }, `${desc} uses the first instance of a duplicate signal ${suffix}`);
+
+  test(t => {
+    for (let i = 0; i < 3; ++i) {
+      const controllers = [];
+      for (let j = 0; j < 3; ++j) {
+        controllers.push(new controllerInterface());
+      }
+      const combinedSignal1 =
+          signalInterface.any([controllers[0].signal, controllers[1].signal]);
+      const combinedSignal2 =
+          signalInterface.any([combinedSignal1, controllers[2].signal]);
+
+      let eventFired = false;
+      combinedSignal2.onabort = t.step_func((e) => {
+        eventFired = true;
+      });
+
+      controllers[i].abort();
+      assert_true(eventFired);
+      assert_true(combinedSignal2.aborted);
+      assert_true(combinedSignal2.reason instanceof DOMException,
+          "signal.reason is a DOMException");
+      assert_equals(combinedSignal2.reason.name, "AbortError",
+          "signal.reason is a AbortError");
+    }
+  }, `${desc} signals are composable ${suffix}`);
+
+  async_test(t => {
+    const controller = new controllerInterface();
+    const timeoutSignal = AbortSignal.timeout(5);
+
+    const combinedSignal = signalInterface.any([controller.signal, timeoutSignal]);
+
+    combinedSignal.onabort = t.step_func_done(() => {
+      assert_true(combinedSignal.aborted);
+      assert_true(combinedSignal.reason instanceof DOMException,
+          "combinedSignal.reason is a DOMException");
+      assert_equals(combinedSignal.reason.name, "TimeoutError",
+          "combinedSignal.reason is a TimeoutError");
+    });
+  }, `${desc} works with signals returned by AbortSignal.timeout() ${suffix}`);
+
+  test(t => {
+    const controller = new controllerInterface();
+    let combined = signalInterface.any([controller.signal]);
+    combined = signalInterface.any([combined]);
+    combined = signalInterface.any([combined]);
+    combined = signalInterface.any([combined]);
+
+    let eventFired = false;
+    combined.onabort = () => {
+      eventFired = true;
+    }
+
+    assert_false(eventFired);
+    assert_false(combined.aborted);
+
+    controller.abort("the reason");
+
+    assert_true(eventFired);
+    assert_true(combined.aborted);
+    assert_equals(combined.reason, "the reason");
+  }, `${desc} works with intermediate signals ${suffix}`);
+
+  test(t => {
+    const controller = new controllerInterface();
+    const signals = [];
+    // The first event should be dispatched on the originating signal.
+    signals.push(controller.signal);
+    // All dependents are linked to `controller.signal` (never to another
+    // composite signal), so this is the order events should fire.
+    signals.push(signalInterface.any([controller.signal]));
+    signals.push(signalInterface.any([controller.signal]));
+    signals.push(signalInterface.any([signals[0]]));
+    signals.push(signalInterface.any([signals[1]]));
+
+    let result = "";
+    for (let i = 0; i < signals.length; i++) {
+      signals[i].addEventListener('abort', () => {
+        result += i;
+      });
+    }
+    controller.abort();
+    assert_equals(result, "01234");
+  }, `Abort events for ${desc} signals fire in the right order ${suffix}`);
+}