CHT002: ValueTask blocked with GetAwaiter().GetResult()

Cause

GetAwaiter().GetResult() is called on a ValueTask or ValueTask<T>.

Rule Description

Calling GetAwaiter().GetResult() on a ValueTask is undefined behavior when the ValueTask is backed by an IValueTaskSource. This pattern:

May cause deadlocks when called on a non-completed ValueTask
Is undefined behavior for IValueTaskSource-backed ValueTasks
Consumes the ValueTask, preventing further usage

The pooled primitives in CryptoHives.Foundation.Threading use IValueTaskSource for their ValueTask implementations, making this pattern particularly dangerous.

How to Fix

Option 1: Use await (Recommended)

Convert to async code:

// Before
valueTask.GetAwaiter().GetResult();

// After
await valueTask;

Option 2: Preserve the ValueTask first

If blocking is absolutely necessary (not recommended):

// Before
valueTask.GetAwaiter().GetResult();

// After
valueTask.Preserve().GetAwaiter().GetResult();

Option 3: Convert to Task first

If blocking is absolutely necessary (not recommended):

// Before
valueTask.GetAwaiter().GetResult();

// After
valueTask.AsTask().GetAwaiter().GetResult();

When to Suppress (not recommended)

Only suppress if you can guarantee:

The ValueTask is already completed (IsCompletedSuccessfully == true)
The ValueTask is backed by a Task, not an IValueTaskSource

ValueTask vt = GetValueTask();
if (vt.IsCompletedSuccessfully)
{
#pragma warning disable CHT002
    vt.GetAwaiter().GetResult(); // Safe only because already completed
#pragma warning restore CHT002
}

Example

Violating Code

public void SyncMethod()
{
    ValueTask vt = asyncEvent.WaitAsync();
    vt.GetAwaiter().GetResult(); // CHT002
}

Fixed Code

// Option 1: Make method async
public async Task AsyncMethod()
{
    await asyncEvent.WaitAsync();
}

// Option 2: Convert to Task first (if blocking is necessary)
public void SyncMethod()
{
    asyncEvent.WaitAsync().AsTask().GetAwaiter().GetResult();
}

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