DEV: Move discourse-chat to the core repo. (#18776)

As part of this move, we are also renaming `discourse-chat` to `chat`.

plugins/chat/test/javascripts/unit/lib/slugify-channel-test.js

@@ -0,0 +1,21 @@
+import { module, test } from "qunit";
+import slugifyChannel from "discourse/plugins/chat/discourse/lib/slugify-channel";
+
+module("Discourse Chat | Unit | slugify-channel", function () {
+  test("defaults", function (assert) {
+    assert.equal(slugifyChannel("Foo bar"), "foo-bar");
+  });
+
+  test("a very long name", function (assert) {
+    const string =
+      "xAq8l5ca2CtEToeMLe2pEr2VUGQBx3HPlxbkDExKrJHp4f7jCVw9id1EQv1N1lYMRdAIiZNnn94Kr0uU0iiEeVO4XkBVmpW8Mknmd";
+
+    assert.equal(slugifyChannel(string), string.toLowerCase().slice(0, -1));
+  });
+
+  test("a cyrillic name", function (assert) {
+    const string = "Русская литература и фольклор";
+
+    assert.equal(slugifyChannel(string), "русская-литература-и-фольклор");
+  });
+});