[BUG] (RunAnd)WaitFor(Request/Response/RequestFinished)Async methods ignore exceptions thrown by action

Context:

• Playwright Version: 1.31.0
• Operating System: any (Windows, Linux, MacOS)
• .NET version: .NET 7
• Browser: Edge (Chromium)

Code Snippet

using System.Threading.Tasks;
using Microsoft.Playwright;

class Program
{
    public static async Task Main()
    {
        using var playwright = await Playwright.CreateAsync();
        await using var browser = await playwright.Chromium.LaunchAsync();
        var page = await browser.NewPageAsync();
        var options = new() { Predicate = r => true };
        var wait = page.RunAndWaitForRequestFinishedAsync(()=>throw new Exception(), options)
        await wait;
        // dead waiting - only timeout and no original exception
    }
}

Description

(RunAnd)WaitFor(Request/Response/RequestFinished)Async method family are implemented by InnerWaitForEventAsync in such a way that ignores exceptions thrown by action. If the action ends up in Failed state (the resulting Task has failed because of some Exception) the actual Wait inside Playwright doesn’t inspect the exception and the failed path ends up in timeout state. The Waiter makes that happen by throwing TimeoutException.

The actual BUG is the fact that the Waiter still waits for some request to filter - but the action that was supposed to trigger some chit-chat that would caused some Requests has thrown in this scenario.

Action throwing -> Exception captured and set on a transient task in WhenAll -> the Waiter waits until timeout.

Secondly there is no CancellationToken to cancel Wait when a caller of (...)WaitFor(...) has some knowledge that the wait became pointless. There is some meaningful amount of time that can be recovered by providing a cancellation here.

So, to summarize:

1. Exceptions from action are missing
2. No cancellation option for Waits

The exact places in code: playwright-dotnet\src\Playwright\Core\Page.cs : 435-438 playwright-dotnet\src\Playwright\Core\Waiter.cs - whole implementation - there should be a RejectOnCancellation or something along those lines.

Patched by: https://github.com/microsoft/playwright-dotnet/pull/2535

[mxschmitt]

Thanks!

[maw136]

PR approved, awaiting merge and release.