Combine Knub's type helpers with Zeppelin's, continue Utility plugin port

backend/src/plugins/Utility/commands/PingCmd.ts

@@ -0,0 +1,53 @@
+import { utilityCmd } from "../types";
+import { noop, trimLines } from "../../../utils";
+import { Message } from "eris";
+
+const { performance } = require("perf_hooks");
+
+export const PingCmd = utilityCmd({
+  trigger: "ping",
+  description: "Test the bot's ping to the Discord API",
+  permission: "can_ping",
+
+  async run({ message: msg, pluginData }) {
+    const times = [];
+    const messages: Message[] = [];
+    let msgToMsgDelay = null;
+
+    for (let i = 0; i < 4; i++) {
+      const start = performance.now();
+      const message = await msg.channel.createMessage(`Calculating ping... ${i + 1}`);
+      times.push(performance.now() - start);
+      messages.push(message);
+
+      if (msgToMsgDelay === null) {
+        msgToMsgDelay = message.timestamp - msg.timestamp;
+      }
+    }
+
+    const highest = Math.round(Math.max(...times));
+    const lowest = Math.round(Math.min(...times));
+    const mean = Math.round(times.reduce((total, ms) => total + ms, 0) / times.length);
+
+    const shard = pluginData.client.shards.get(pluginData.client.guildShardMap[pluginData.guild.id]);
+
+    msg.channel.createMessage(
+      trimLines(`
+      **Ping:**
+      Lowest: **${lowest}ms**
+      Highest: **${highest}ms**
+      Mean: **${mean}ms**
+      Time between ping command and first reply: **${msgToMsgDelay}ms**
+      Shard latency: **${shard.latency}ms**
+    `),
+    );
+
+    // Clean up test messages
+    pluginData.client
+      .deleteMessages(
+        messages[0].channel.id,
+        messages.map(m => m.id),
+      )
+      .catch(noop);
+  },
+});