Add test for Context Injection Scope (#13)

Example for issue #12

SpecFlow.DependencyInjection.Tests/ContextInjectionScope.feature

@@ -0,0 +1,17 @@
+Feature: ContextInjectionScope
+    Issue #12: Scoping Context Injection to Scenario Execution Lifetimes
+    https://github.com/solidtoken/SpecFlow.DependencyInjection/issues/12
+
+Scenario: Assert Context Is Scoped To Scenario Execution
+    The multiply and increase steps are intentionally implemented using different bindings.
+    Assert that they can operate on the same context (within the scenario executing).
+	Given I have test context with number 5
+    When I multiply the test context number by 2
+    And I increase the test context number by 3
+    Then the test context number should be 13
+
+Scenario: Assert Context Is Scoped To Scenario Execution (No Spill)
+    Assert that the test context does not spill over to other scenarios.
+    Note that this assumes this scenario will be run after the above one (ie don't use parallel tests).
+    Given I have a test context
+    Then the test context number should be 0

SpecFlow.DependencyInjection.Tests/ContextInjectionScopeSteps.cs

@@ -0,0 +1,75 @@
+using System;
+using System.Diagnostics;
+using TechTalk.SpecFlow;
+using Xunit;
+
+namespace SolidToken.SpecFlow.DependencyInjection.Tests
+{
+    public class TestContext
+    {
+        public int Number { get; set; }
+    }
+
+    [Binding]
+    public class ContextInjectionScopeSteps
+    {
+        private readonly TestContext _context;
+
+        public ContextInjectionScopeSteps(TestContext context)
+        {
+            _context = context;
+        }
+
+        [Given(@"I have a test context")]
+        public void GivenIHaveATestContext()
+        {
+            // NOOP
+        }
+
+        [Given(@"I have test context with number (.*)")]
+        public void GivenIHaveTestContextWithNumber(int number)
+        {
+            _context.Number = number;
+        }
+
+        [Then(@"the test context number should be (.*)")]
+        public void ThenTheTestContextNumberShouldBe(int expected)
+        {
+            Assert.Equal(expected, _context.Number);
+        }
+    }
+
+    [Binding]
+    public class MultiplySteps
+    {
+        private readonly TestContext _context;
+
+        public MultiplySteps(TestContext context)
+        {
+            _context = context;
+        }
+
+        [When(@"I multiply the test context number by (.*)")]
+        public void WhenIMultiplyTheTestContextNumberBy(int multiply)
+        {
+            _context.Number *= multiply;
+        }
+    }
+
+    [Binding]
+    public class IncreaseSteps
+    {
+        private readonly TestContext _context;
+
+        public IncreaseSteps(TestContext context)
+        {
+            _context = context;
+        }
+
+        [When(@"I increase the test context number by (.*)")]
+        public void WhenIIncreaseTheTestContextNumberBy(int increase)
+        {
+            _context.Number += increase;
+        }
+    }
+}

SpecFlow.DependencyInjection.Tests/SpecFlow.DependencyInjection.Tests.csproj

@@ -33,6 +33,11 @@
   </ItemGroup>
 
   <ItemGroup>
+    <Compile Update="ContextInjectionScope.feature.cs">
+      <DesignTime>True</DesignTime>
+      <AutoGen>True</AutoGen>
+      <DependentUpon>ContextInjectionScope.feature</DependentUpon>
+    </Compile>
     <Compile Update="DependencyInjectionPlugin.feature.cs">
       <DesignTime>True</DesignTime>
       <AutoGen>True</AutoGen>
@@ -47,6 +52,10 @@
   </ItemGroup>
 
   <ItemGroup>
+    <SpecFlowFeatureFiles Update="ContextInjectionScope.feature">
+      <Generator>SpecFlowSingleFileGenerator</Generator>
+      <LastGenOutput>ContextInjectionScope.feature.cs</LastGenOutput>
+    </SpecFlowFeatureFiles>
     <SpecFlowFeatureFiles Update="DependencyInjectionPlugin.feature">
       <Generator>SpecFlowSingleFileGenerator</Generator>
     </SpecFlowFeatureFiles>

SpecFlow.DependencyInjection.Tests/TestDependencies.cs

@@ -15,6 +15,9 @@ public static IServiceCollection CreateServices()
             // Add test dependencies
             services.AddTransient<ITestService, TestService>();
 
+            // ContextInjectionScope (by using AddScoped instead of AddTransient, the context will be scoped to the Feature across bindings)
+            services.AddScoped<TestContext>();
+
             // NOTE: This line is essential so that Microsoft.Extensions.DependencyInjection knows
             // about the SpecFlow bindings (something normally BoDi does automatically).
             // TODO: Find out if we can make this part of the Plugin