Merge deno_cli_snapshots into deno_cli (#3064)

cli/js/metrics.ts

@@ -0,0 +1,28 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+import * as dispatch from "./dispatch.ts";
+import { sendSync } from "./dispatch_json.ts";
+
+export interface Metrics {
+  opsDispatched: number;
+  opsCompleted: number;
+  bytesSentControl: number;
+  bytesSentData: number;
+  bytesReceived: number;
+}
+
+/** Receive metrics from the privileged side of Deno.
+ *
+ *      > console.table(Deno.metrics())
+ *      ┌──────────────────┬────────┐
+ *      │     (index)      │ Values │
+ *      ├──────────────────┼────────┤
+ *      │  opsDispatched   │   9    │
+ *      │   opsCompleted   │   9    │
+ *      │ bytesSentControl │  504   │
+ *      │  bytesSentData   │   0    │
+ *      │  bytesReceived   │  856   │
+ *      └──────────────────┴────────┘
+ */
+export function metrics(): Metrics {
+  return sendSync(dispatch.OP_METRICS);
+}