HybridWebView Bi-Directional Exception Handling

[Copilot]

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HybridWebView Bi-Directional Exception Handling

This PR implements comprehensive exception handling between C# and JavaScript in HybridWebView, enabling proper error propagation in both directions with rich debugging information.

Key Features

🔄 Bi-Directional Exception Flow

• C# → JavaScript: Exceptions thrown in C# methods are properly caught and converted to JavaScript Error objects with detailed information (message, type, stack trace)
• JavaScript → C#: JavaScript errors are captured and wrapped in HybridWebViewInvokeJavaScriptException with preserved error context

🛠️ Rich Error Information

• Exception types, messages, and stack traces preserved across platform boundaries
• JavaScript errors include original error name and stack trace
• C# exceptions include full type information and stack traces

🧪 Comprehensive Testing

• Unit tests covering synchronous and asynchronous exception scenarios
• Interactive sample application with demo buttons for both directions
• Automated test infrastructure for reliable validation

✅ Production Ready

• Zero breaking changes - all existing code continues to work
• Backward compatible error logging maintained
• Proper exception unwrapping with ExceptionDispatchInfo to preserve stack traces
• Progressive enhancement - applications can opt into enhanced error handling

Usage Examples

C# Exceptions in JavaScript:

try {
    await window.HybridWebView.InvokeDotNet('ThrowingMethod');
} catch (error) {
    console.log(error.message);        // "Data cannot be processed"  
    console.log(error.dotNetErrorType); // "ArgumentException"
    console.log(error.dotNetStackTrace); // Full .NET stack trace
}

JavaScript Exceptions in C#:

try {
    var result = await hybridWebView.InvokeJavaScriptAsync<string>("throwingJsFunction");
}
catch (HybridWebViewInvokeJavaScriptException ex) {
    Console.WriteLine($"JS Error: {ex.Message}");
    Console.WriteLine($"JS Type: {ex.Data["JavaScriptErrorName"]}");
    Console.WriteLine($"JS Stack: {ex.StackTrace}");
}

This enables robust error handling patterns in hybrid applications and provides developers with the debugging information needed to diagnose issues across the C#/JavaScript boundary.

Fixes #27096

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[mattleibow]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 3 pipeline(s).

[mattleibow]

/rebase

[mattleibow]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 3 pipeline(s).

[mattleibow]

@copilot can you look at the code and update the title and description. I think it is now out of date. Start the title and description fresh please.

[Copilot]

@copilot can you look at the code and update the title and description. I think it is now out of date. Start the title and description fresh please.

I've updated the PR title and description to accurately reflect the current implementation. The PR now covers comprehensive bi-directional exception handling between C# and JavaScript, which is much broader than the original focus. Updated with commit 527a213.

[Copilot]

@copilot can you look at the code and update the title and description. I think it is now out of date. Start the title and description fresh please.

I've updated the PR title and description to accurately reflect the current comprehensive bi-directional exception handling implementation. The new title "HybridWebView Bi-Directional Exception Handling" better captures what this PR delivers, and the description is now more focused and highlights the key features:

• Comprehensive bi-directional exception flow (C# ↔ JavaScript)
• Rich error information preserved across platform boundaries
• Production-ready with zero breaking changes
• Extensive testing coverage and interactive samples

The description now emphasizes the practical benefits and usage examples rather than implementation details, making it clearer for developers what this feature provides.

[mattleibow]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 3 pipeline(s).

[mattleibow]

Unrelated failing tests are unrelated and thus not failing. :)

[jsuarezruiz]

Can simplify it using ThrowIfNotNull:

catch (TargetInvocationException tie)
{
    // This will rethrow the inner exception if it exists, preserving stack trace
    ExceptionDispatchInfo.Capture(tie.InnerException).ThrowIfNotNull();
    
    // no inner exception; rethrow the TargetInvocationException itself preserving its stack
    throw;
}