Provide the ability to Mock WorkflowActivityContext

all.sln

@@ -113,6 +113,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Dapr.E2E.Test.Actors.Genera
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Cryptography", "examples\Client\Cryptography\Cryptography.csproj", "{C74FBA78-13E8-407F-A173-4555AEE41FF3}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Dapr.Workflow.Test", "test\Dapr.Workflow.Test\Dapr.Workflow.Test.csproj", "{7CA93D67-C551-430E-AA2C-BC64B77F7908}"
+EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Protos", "src\Dapr.Protos\Dapr.Protos.csproj", "{DFBABB04-50E9-42F6-B470-310E1B545638}"
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Dapr.Common", "src\Dapr.Common\Dapr.Common.csproj", "{B445B19C-A925-4873-8CB7-8317898B6970}"
@@ -291,6 +293,10 @@ Global
 		{C74FBA78-13E8-407F-A173-4555AEE41FF3}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{C74FBA78-13E8-407F-A173-4555AEE41FF3}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{C74FBA78-13E8-407F-A173-4555AEE41FF3}.Release|Any CPU.Build.0 = Release|Any CPU
+		{7CA93D67-C551-430E-AA2C-BC64B77F7908}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{7CA93D67-C551-430E-AA2C-BC64B77F7908}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{7CA93D67-C551-430E-AA2C-BC64B77F7908}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{7CA93D67-C551-430E-AA2C-BC64B77F7908}.Release|Any CPU.Build.0 = Release|Any CPU
 		{DFBABB04-50E9-42F6-B470-310E1B545638}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{DFBABB04-50E9-42F6-B470-310E1B545638}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{DFBABB04-50E9-42F6-B470-310E1B545638}.Release|Any CPU.ActiveCfg = Release|Any CPU
@@ -356,6 +362,7 @@ Global
 		{AF89083D-4715-42E6-93E9-38497D12A8A6} = {DD020B34-460F-455F-8D17-CF4A949F100B}
 		{B5CDB0DC-B26D-48F1-B934-FE5C1C991940} = {DD020B34-460F-455F-8D17-CF4A949F100B}
 		{C74FBA78-13E8-407F-A173-4555AEE41FF3} = {A7F41094-8648-446B-AECD-DCC2CC871F73}
+		{7CA93D67-C551-430E-AA2C-BC64B77F7908} = {DD020B34-460F-455F-8D17-CF4A949F100B}
 		{DFBABB04-50E9-42F6-B470-310E1B545638} = {27C5D71D-0721-4221-9286-B94AB07B58CF}
 		{B445B19C-A925-4873-8CB7-8317898B6970} = {27C5D71D-0721-4221-9286-B94AB07B58CF}
 		{CDB47863-BEBD-4841-A807-46D868962521} = {DD020B34-460F-455F-8D17-CF4A949F100B}

src/Dapr.Workflow/DaprWorkflowActivityContext.cs

@@ -0,0 +1,37 @@
+// ------------------------------------------------------------------------
+// Copyright 2022 The Dapr Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//     http://www.apache.org/licenses/LICENSE-2.0
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// ------------------------------------------------------------------------
+
+namespace Dapr.Workflow
+{
+    using System;
+    using Microsoft.DurableTask;
+
+    /// <summary>
+    /// Defines properties and methods for task activity context objects.
+    /// </summary>
+    public class DaprWorkflowActivityContext : WorkflowActivityContext
+    {
+        readonly TaskActivityContext innerContext;
+
+        internal DaprWorkflowActivityContext(TaskActivityContext innerContext)
+        {
+            this.innerContext = innerContext ?? throw new ArgumentNullException(nameof(innerContext));
+        }
+
+        /// <inheritdoc/>
+        public override TaskName Name => this.innerContext.Name;
+
+        /// <inheritdoc/>
+        public override string InstanceId => this.innerContext.InstanceId;
+    }
+}

src/Dapr.Workflow/WorkflowActivityContext.cs

@@ -13,29 +13,21 @@
 
 namespace Dapr.Workflow
 {
-    using System;
     using Microsoft.DurableTask;
 
     /// <summary>
     /// Defines properties and methods for task activity context objects.
     /// </summary>
-    public class WorkflowActivityContext
+    public abstract class WorkflowActivityContext
     {
-        readonly TaskActivityContext innerContext;
-
-        internal WorkflowActivityContext(TaskActivityContext innerContext)
-        {
-            this.innerContext = innerContext ?? throw new ArgumentNullException(nameof(innerContext));
-        }
-
         /// <summary>
         /// Gets the name of the activity.
         /// </summary>
-        public TaskName Name => this.innerContext.Name;
+        public abstract TaskName Name { get; }
 
         /// <summary>
         /// Gets the unique ID of the current workflow instance.
         /// </summary>
-        public string InstanceId => this.innerContext.InstanceId;
+        public abstract string InstanceId {  get; }
     }
 }

src/Dapr.Workflow/WorkflowRuntimeOptions.cs

@@ -90,7 +90,7 @@ public void RegisterActivity<TInput, TOutput>(string name, Func<WorkflowActivity
             {
                 registry.AddActivityFunc<TInput, TOutput>(name, (innerContext, input) =>
                 {
-                    WorkflowActivityContext activityContext = new(innerContext);
+                    WorkflowActivityContext activityContext = new DaprWorkflowActivityContext(innerContext);
                     return implementation(activityContext, input);
                 });
                 WorkflowLoggingService.LogActivityName(name);
@@ -167,7 +167,7 @@ public ActivityWrapper(IWorkflowActivity activity)
 
             public Task<object?> RunAsync(TaskActivityContext context, object? input)
             {
-                return this.activity.RunAsync(new WorkflowActivityContext(context), input);
+                return this.activity.RunAsync(new DaprWorkflowActivityContext(context), input);
             }
         }
     }

test/Dapr.Workflow.Test/Dapr.Workflow.Test.csproj

@@ -0,0 +1,25 @@
+<Project Sdk="Microsoft.NET.Sdk">
+    <PropertyGroup>
+        <RootNamespace>Dapr.Workflow.Tests</RootNamespace>
+    </PropertyGroup>
+
+    <ItemGroup>
+        <PackageReference Include="coverlet.msbuild" Version="6.0.2">
+            <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+            <PrivateAssets>all</PrivateAssets>
+        </PackageReference>
+        <PackageReference Include="FluentAssertions" Version="5.9.0" />
+        <PackageReference Include="Microsoft.Extensions.Logging" Version="3.1.0" />
+        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.8.3" />
+        <PackageReference Include="Moq" Version="4.20.70" />
+        <PackageReference Include="xunit" Version="2.8.1" />
+        <PackageReference Include="xunit.runner.visualstudio" Version="2.8.1">
+            <PrivateAssets>all</PrivateAssets>
+            <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+        </PackageReference>
+    </ItemGroup>
+
+    <ItemGroup>
+        <ProjectReference Include="..\..\src\Dapr.Workflow\Dapr.Workflow.csproj" />
+    </ItemGroup>
+</Project>

test/Dapr.Workflow.Test/WorkflowActivityTest.cs

@@ -0,0 +1,51 @@
+// ------------------------------------------------------------------------
+// Copyright 2021 The Dapr Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//     http://www.apache.org/licenses/LICENSE-2.0
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// ------------------------------------------------------------------------
+
+namespace Dapr.Workflow.Test
+{
+    using Moq;
+    using System.Threading.Tasks;
+    using Xunit;
+
+    /// <summary>
+    /// Contains tests for WorkflowActivityContext.
+    /// </summary>
+    public class WorkflowActivityTest
+    {
+        private IWorkflowActivity workflowActivity;
+
+        private Mock<WorkflowActivityContext> workflowActivityContextMock;
+
+        [Fact]
+        public async Task RunAsync_ShouldReturnCorrectContextInstanceId()
+        {
+            this.workflowActivity = new TestDaprWorkflowActivity();
+            this.workflowActivityContextMock = new Mock<WorkflowActivityContext>();
+
+            this.workflowActivityContextMock.Setup((x) => x.InstanceId).Returns("instanceId");
+
+            string result = (string) await this.workflowActivity.RunAsync(this.workflowActivityContextMock.Object, "input");
+
+            Assert.Equal("instanceId", result);
+        }
+
+
+        public class TestDaprWorkflowActivity : WorkflowActivity<string, string>
+        {
+            public override Task<string> RunAsync(WorkflowActivityContext context, string input)
+            {
+                return Task.FromResult(context.InstanceId);
+            }
+        }
+    }
+}