From 21288baf831586756cb7c9c6642a2254b5cc9e9a Mon Sep 17 00:00:00 2001
From: Abram Sanderson <Abram.Sanderson@microsoft.com>
Date: Mon, 16 Sep 2024 15:37:50 -0700
Subject: [PATCH] Add diagnostics to ConsensusQueue in handle validation tests
 (#22531)

## Description

Modifies `ConsensusQueue`'s generic "store a piece of data"
implementation in `handleValidation.ts` to give more information on a
couple theoretical error methods. This test timed out on a recent
tinylicious run where based on telemetry, it seems like the test got
past the point of loading the 2nd container. Thus it was likely a
deadlock awaiting this promise. I've been unable to reproduce this
behavior locally. The goal here is to get information about the failure
mode the next time this race condition happens.

---------

Co-authored-by: Abram Sanderson <absander@microsoft.com>
---
 .../src/test/handleValidation.spec.ts         | 28 +++++++++++++------
 1 file changed, 20 insertions(+), 8 deletions(-)

diff --git a/packages/test/test-end-to-end-tests/src/test/handleValidation.spec.ts b/packages/test/test-end-to-end-tests/src/test/handleValidation.spec.ts
index 10bcf968c178..3c3d771311a2 100644
--- a/packages/test/test-end-to-end-tests/src/test/handleValidation.spec.ts
+++ b/packages/test/test-end-to-end-tests/src/test/handleValidation.spec.ts
@@ -39,6 +39,7 @@ import {
 	createAndAttachContainer,
 	ITestFluidObject,
 	type ITestObjectProvider,
+	timeoutAwait,
 } from "@fluidframework/test-utils/internal";
 import {
 	ITree,
@@ -376,14 +377,25 @@ describeCompat("handle validation", "NoCompat", (getTestObjectProvider, apis) =>
 						await queue.add(handle);
 					},
 					async readHandle(): Promise<unknown> {
-						const value = await new Promise((resolve, reject) => {
-							queue
-								.acquire(async (result: FluidObject) => {
-									resolve(result);
-									return ConsensusResult.Release;
-								})
-								.catch((error) => reject(error));
-						});
+						const value = await timeoutAwait(
+							new Promise((resolve, reject) => {
+								queue
+									.acquire(async (result: FluidObject) => {
+										resolve(result);
+										return ConsensusResult.Release;
+									})
+									.then((wasNonempty) => {
+										if (!wasNonempty) {
+											// This could happen if a test never calls `storeHandle` before attempting to read it.
+											// Other modes of failure are possible (e.g. correctness issues in ConsensusQueue causing it to have the wrong data).
+											// Resolving the promise with `undefined` here could be another reasonable option, but this gives slightly more information.
+											reject(new Error("No values found in consensus queue."));
+										}
+									})
+									.catch((error) => reject(error));
+							}),
+							{ errorMsg: "Timeout waiting for acquiring value from consensus queue." },
+						);
 						return value;
 					},
 					handle: queue.handle,