Add support for AbortController/AbortSignal (#4757)

1 files changed, 56 insertions, 0 deletions

diff --git a/cli/js/tests/abort_controller_test.ts b/cli/js/tests/abort_controller_test.ts
new file mode 100644
index 000000000..ecc1abb88
--- /dev/null
+++ b/cli/js/tests/abort_controller_test.ts
@@ -0,0 +1,56 @@
+import { unitTest, assert, assertEquals } from "./test_util.ts";
+
+unitTest(function basicAbortController() {
+  const controller = new AbortController();
+  assert(controller);
+  const { signal } = controller;
+  assert(signal);
+  assertEquals(signal.aborted, false);
+  controller.abort();
+  assertEquals(signal.aborted, true);
+});
+
+unitTest(function signalCallsOnabort() {
+  const controller = new AbortController();
+  const { signal } = controller;
+  let called = false;
+  signal.onabort = (evt): void => {
+    assert(evt);
+    assertEquals(evt.type, "abort");
+    called = true;
+  };
+  controller.abort();
+  assert(called);
+});
+
+unitTest(function signalEventListener() {
+  const controller = new AbortController();
+  const { signal } = controller;
+  let called = false;
+  signal.addEventListener("abort", function (ev) {
+    assert(this === signal);
+    assertEquals(ev.type, "abort");
+    called = true;
+  });
+  controller.abort();
+  assert(called);
+});
+
+unitTest(function onlyAbortsOnce() {
+  const controller = new AbortController();
+  const { signal } = controller;
+  let called = 0;
+  signal.addEventListener("abort", () => called++);
+  signal.onabort = (): void => {
+    called++;
+  };
+  controller.abort();
+  assertEquals(called, 2);
+  controller.abort();
+  assertEquals(called, 2);
+});
+
+unitTest(function controllerHasProperToString() {
+  const actual = Object.prototype.toString.call(new AbortController());
+  assertEquals(actual, "[object AbortController]");
+});