Testing Machine Intelligence Runtimes

using System.ComponentModel.DataAnnotations;

/// <summary>Captures the evidence asserted by a runtime test.</summary>
public sealed record TestCaseResult
{
    /// <summary>Gets whether the invariant passed.</summary>
    [Display(Name = "Passed")]
    public required bool Passed { get; init; }
}

/// <summary>Verifies that a terminal run cannot return to running.</summary>
public sealed class RunStateMachineTests
{
    /// <summary>Rejects a transition from completed to running.</summary>
    /// <param name="cancellationToken">Signals cancellation of the asynchronous test.</param>
    [Fact]
    public async Task TryTransitionAsync_CompletedToRunning_ReturnsFalse(
        CancellationToken cancellationToken = default)
    {
        // Arrange
        var stateMachine = CreateStateMachineWithCompletedRun();
        var transition = new RunTransition
        {
            FromState = RunLifecycleState.Completed,
            ToState = RunLifecycleState.Running,
            EventType = "resume",
            ConcurrencyToken = "expected-token"
        };

        // Act
        var applied = await stateMachine.TryTransitionAsync(
            "run-123",
            transition,
            cancellationToken);

        // Assert
        Assert.False(applied);
    }
}