FlowLite.Testing 8.0.0

FlowLite.Testing

FlowLite.Testing is a minimalistic and fluent testing library designed for writing expressive and structured unit tests for your FlowLite FSM workflows. It builds on top of FlowLite, enabling easy assertions for:

• State transitions
• Entity lifecycle
• Log messages
• Transition history
• Entity deletion

Features

• Fluent Assertions — expressive .Should().Allow(...), .BeIn(...), .Logs(), etc.
• Trigger Validation — .Assert().Allow(...) or .NotAllow(...).
• Entity Validation — validate entity changes or deletions via .HaveEntity(...) and .DeleteEntity().
• Log Inspection — assert warnings, errors, or specific messages.
• History Validation — verify transition path, length, or contents.
• Minimal & Fast — no dependencies on other testing libraries or frameworks.
• Designed for full compatibility with FlowLite FSM.

Installation

To install the latest version of the FlowLite.Testing NuGet package:

NuGet Package Manager

Install-Package FlowLite.Testing -Version 8.0.0

.NET CLI

dotnet add package FlowLite.Abstractions --version 8.0.0
dotnet add package FlowLite.Testing --version 8.0.0

Usage Guide

Required Namespaces

using FlowLite.Testing;
using FlowLite.Testing.Assertions;

Fluent Testing API

1. Assert a Trigger is Allowed or Rejected

fsm.Should().Allow(OrderTrigger.Pay);
fsm.Should().NotAllow(OrderTrigger.Cancel);

2. Verify Current State

fsm.Should().BeIn(OrderState.Paid);

3. Entity Assertions

fsm.Should().NotNullEntity();
fsm.Should().HaveEntity(order =>
{
    Assert.Equal("Shipped", order?.Status);
});

4. Log Assertions

fsm.Should().Logs().Log(LogLevel.Warning, "invalid transition");
fsm.Should().Logs().BeFinalState();
fsm.Should().Logs().ContainFinalStateLog();
fsm.Should().Logs().MatchSnapshot(new[] { "FSM initialized", "Transitioned to Paid" });

5. History Assertions

fsm.Should().History()
    .StartWith(OrderState.Created)
    .HaveInHistory(OrderState.Created, OrderState.Paid, OrderState.Shipped)
    .Contains(OrderTrigger.Pay, OrderState.Paid)
    .HaveLength(3)
    .ContainsTrigger(OrderTrigger.Ship);

Trigger-Only Assertions

You can use .Assert() style for concise checks:

fsm.Assert().Allow(OrderTrigger.Pay);
fsm.Assert().NotAllow(OrderTrigger.Cancel);

Minimal sample

fsm.AddTransition(OrderState.Created, OrderTrigger.Pay, OrderState.Paid, async (_, ctx) =>
   {
       ctx.Entity!.Status = "Paid";
       await Task.CompletedTask;
   });
await fsm.FireAsync(OrderTrigger.Pay);
fsm.Should()
    .BeIn(OrderState.Paid)
    .NotNullEntity()
    .Logs().Log(LogLevel.Info, "Paid");

License

This project is licensed under the MIT License.