Adding unit test to cover Parallel event scenario

Author: viktorkryzhanovksyilangai

test/WorkflowCore.IntegrationTests/Scenarios/ParallelEventsScenario.cs

@@ -0,0 +1,91 @@
+using System;
+using WorkflowCore.Interface;
+using WorkflowCore.Models;
+using Xunit;
+using FluentAssertions;
+using WorkflowCore.Testing;
+using System.Threading;
+
+namespace WorkflowCore.IntegrationTests.Scenarios
+{
+    public sealed class ParallelEventsScenario
+        : WorkflowTest<ParallelEventsScenario.ParallelEventsWorkflow, ParallelEventsScenario.MyDataClass>
+    {
+        private const string EVENT_KEY = nameof(EVENT_KEY);
+
+        public class MyDataClass
+        {
+            public string StrValue1 { get; set; }
+            public string StrValue2 { get; set; }
+        }
+
+        public class ParallelEventsWorkflow : IWorkflow<MyDataClass>
+        {
+            public string Id => "EventWorkflow";
+            public int Version => 1;
+            public void Build(IWorkflowBuilder<MyDataClass> builder)
+            {
+                builder
+                    .StartWith(context => ExecutionResult.Next())
+                    .Parallel()
+                    .Do(then =>
+                        then.WaitFor("Event1", data => EVENT_KEY).Then(x =>
+                        {
+                            Thread.Sleep(300);
+                            return ExecutionResult.Next();
+                        }))
+                    .Do(then =>
+                        then.WaitFor("Event2", data => EVENT_KEY).Then(x =>
+                        {
+                            Thread.Sleep(100);
+                            return ExecutionResult.Next();
+                        }))
+                   .Do(then =>
+                        then.WaitFor("Event3", data => EVENT_KEY).Then(x =>
+                        {
+                            Thread.Sleep(1000);
+                            return ExecutionResult.Next();
+                        }))
+                   .Do(then =>
+                        then.WaitFor("Event4", data => EVENT_KEY).Then(x =>
+                        {
+                            Thread.Sleep(100);
+                            return ExecutionResult.Next();
+                        }))
+                   .Do(then =>
+                        then.WaitFor("Event5", data => EVENT_KEY).Then(x =>
+                        {
+                            Thread.Sleep(100);
+                            return ExecutionResult.Next();
+                        }))
+                .Join()
+                .Then(x =>
+                {
+                    return ExecutionResult.Next();
+                });
+            }
+        }
+
+        public ParallelEventsScenario()
+        {
+            Setup();
+        }
+
+        [Fact]
+        public void Scenario()
+        {
+            var eventKey = Guid.NewGuid().ToString();
+            var workflowId = StartWorkflow(new MyDataClass { StrValue1 = eventKey, StrValue2 = eventKey });
+            Host.PublishEvent("Event1", EVENT_KEY, "Pass1");
+            Host.PublishEvent("Event2", EVENT_KEY, "Pass2");
+            Host.PublishEvent("Event3", EVENT_KEY, "Pass3");
+            Host.PublishEvent("Event4", EVENT_KEY, "Pass4");
+            Host.PublishEvent("Event5", EVENT_KEY, "Pass5");
+
+            WaitForWorkflowToComplete(workflowId, TimeSpan.FromSeconds(30));
+
+            GetStatus(workflowId).Should().Be(WorkflowStatus.Complete);
+            UnhandledStepErrors.Count.Should().Be(0);
+        }
+    }
+}