move js unit tests to cli/tests (#5678)

cli/tests/unit/custom_event_test.ts

@@ -0,0 +1,27 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+import { unitTest, assertEquals } from "./test_util.ts";
+
+unitTest(function customEventInitializedWithDetail(): void {
+  const type = "touchstart";
+  const detail = { message: "hello" };
+  const customEventInit = {
+    bubbles: true,
+    cancelable: true,
+    detail,
+  } as CustomEventInit;
+  const event = new CustomEvent(type, customEventInit);
+
+  assertEquals(event.bubbles, true);
+  assertEquals(event.cancelable, true);
+  assertEquals(event.currentTarget, null);
+  assertEquals(event.detail, detail);
+  assertEquals(event.isTrusted, false);
+  assertEquals(event.target, null);
+  assertEquals(event.type, type);
+});
+
+unitTest(function toStringShouldBeWebCompatibility(): void {
+  const type = "touchstart";
+  const event = new CustomEvent(type, {});
+  assertEquals(event.toString(), "[object CustomEvent]");
+});