tests: add channels types (#840)

tests/channels/get_channels.ts

@@ -0,0 +1,27 @@
+import { cache } from "../../src/cache.ts";
+import { createChannel } from "../../src/helpers/channels/create_channel.ts";
+import { deleteChannel } from "../../src/helpers/channels/delete_channel.ts";
+import { defaultTestOptions, tempData } from "../ws/start_bot.ts";
+import { delayUntil } from "../util/delay_until.ts";
+import {editChannel} from "../../src/helpers/channels/edit_channel.ts";
+import {assertEquals} from "../deps.ts";
+import {getChannel} from "../../src/helpers/channels/get_channel.ts";
+import {botId} from "../../src/bot.ts";
+import {getChannels} from "../../src/helpers/channels/get_channels.ts";
+
+Deno.test({
+  name: "[channel] get channels.",
+  async fn() {
+    cache.channels.clear();
+
+    // Delete the channel now without a reason
+    await getChannels(tempData.guildId);
+    await delayUntil(3000, () => cache.channels.size > 0);
+
+    assertEquals(
+        cache.channels.size > 0,
+        true,
+    );
+  },
+  ...defaultTestOptions,
+});