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node_modules/@weborigami/language/test/runtime/EventTargetMixin.test.js

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+import assert from "node:assert";
+import { describe, test } from "node:test";
+import EventTargetMixin from "../../src/runtime/EventTargetMixin.js";
+
+class EventTargetTest extends EventTargetMixin(Object) {}
+
+describe("EventTargetMixin", () => {
+  test("add and dispatch event", () => {
+    const fixture = new EventTargetTest();
+    const event = new Event("test");
+    let callCount = 0;
+    const callback = () => {
+      callCount++;
+    };
+    fixture.addEventListener("test", callback);
+    // Add twice, ensure that the callback is only called once.
+    fixture.addEventListener("test", callback);
+    const dispatched = fixture.dispatchEvent(event);
+    assert(dispatched);
+    assert.equal(callCount, 1);
+  });
+
+  test("dispatch event with no listeners", () => {
+    const fixture = new EventTargetTest();
+    const event = new Event("test");
+    const takeDefaultAction = fixture.dispatchEvent(event);
+    assert(takeDefaultAction);
+  });
+
+  test("remove event listener", () => {
+    const fixture = new EventTargetTest();
+    const event = new Event("test");
+    let callCount = 0;
+    const callback = () => {
+      callCount++;
+    };
+    fixture.addEventListener("test", callback);
+    fixture.removeEventListener("test", callback);
+    fixture.dispatchEvent(event);
+    assert.equal(callCount, 0);
+  });
+
+  test("stop immediate propagation", () => {
+    const fixture = new EventTargetTest();
+    const event = new Event("test");
+    let callCount = 0;
+    fixture.addEventListener("test", (event) => {
+      callCount++;
+      event.stopImmediatePropagation();
+    });
+    fixture.addEventListener("test", () => {
+      callCount++;
+    });
+    fixture.dispatchEvent(event);
+    assert.equal(callCount, 1);
+  });
+
+  test("prevent default", () => {
+    const fixture = new EventTargetTest();
+    const event = new Event("test");
+    fixture.addEventListener("test", (event) => {
+      event.preventDefault();
+    });
+    const takeDefaultAction = fixture.dispatchEvent(event);
+    assert(!takeDefaultAction);
+    assert(event.defaultPrevented);
+  });
+});