Handle batched code mode tail events

packages/workshop-backend/__tests__/code-mode-tail.test.ts

@@ -0,0 +1,23 @@
+import { expect, it, vi } from "vitest";
+import { CodeModeTailLoopback } from "../src/overseer.js";
+const trace = (rpcMethod: string) => ({
+  event: { rpcMethod }, logs: [], exceptions: [], diagnosticsChannelEvents: [],
+}) as unknown as TraceItem;
+it("delivers only a run paired with one verify", async () => {
+  const deliverCodeModeTrace = vi.fn(async () => undefined);
+  const loopback = { ctx: {
+    props: { executionId: "execution", overseerId: "overseer" },
+    exports: { OverseerDurableObject: {
+      idFromString: (id: string) => id,
+      get: () => ({ deliverCodeModeTrace }),
+    } },
+  } };
+  const tail = (...methods: string[]) => CodeModeTailLoopback.prototype.tail.call(
+    loopback as unknown as CodeModeTailLoopback, methods.map(trace));
+  await tail("verify", "run");
+  expect(deliverCodeModeTrace).toHaveBeenCalledOnce();
+  expect(deliverCodeModeTrace.mock.calls[0]?.[1]).toMatchObject({ event: { rpcMethod: "run" } });
+  for (const methods of [["verify", "other"], ["verify", "verify", "run"], ["run", "run"]]) {
+    deliverCodeModeTrace.mockClear(); await tail(...methods); expect(deliverCodeModeTrace).not.toHaveBeenCalled();
+  }
+});

packages/workshop-backend/src/overseer.ts

@@ -7235,6 +7235,13 @@ export class CodeModeTailLoopback extends WorkerEntrypoint<Cloudflare.Env, CodeM
   //   on workerd console, need to fix that first.
 
   async tail(events: TraceItem[]) {
+    if (events.length === 2) {
+      const [first, second] = events;
+      const firstMethod = first.event && "rpcMethod" in first.event ? first.event.rpcMethod : undefined;
+      const secondMethod = second.event && "rpcMethod" in second.event ? second.event.rpcMethod : undefined;
+      if (firstMethod === "verify" && secondMethod === "run") events = [second];
+      else if (firstMethod === "run" && secondMethod === "verify") events = [first];
+    }
     if (events.length != 1) {
       logger.error("unexpected code mode trace size", {
         event: "code.mode.trace.size.unexpected",