Add tests for CI providers to ContinuousIntegrationBuild

src/DotNet.ReproducibleBuilds/DotNet.ReproducibleBuilds.props

@@ -12,17 +12,23 @@
 
   <!-- Enable ContinuousIntegrationBuild when running on CI -->
 
-  <!-- Azure Pipelines / DevOpsServer -->
+  <!-- Azure Pipelines / DevOpsServer
+  https://learn.microsoft.com/en-us/azure/devops/pipelines/build/variables?view=azure-devops&tabs=yaml#system-variables-devops-services
+  -->
   <PropertyGroup Condition="'$(TF_BUILD)' == 'true'">
     <ContinuousIntegrationBuild>true</ContinuousIntegrationBuild>
   </PropertyGroup>
 
-  <!-- GitHub Actions -->
+  <!-- GitHub Actions
+  https://docs.github.com/en/actions/writing-workflows/choosing-what-your-workflow-does/store-information-in-variables#default-environment-variables
+  -->
   <PropertyGroup Condition="'$(GITHUB_ACTIONS)' == 'true'">
     <ContinuousIntegrationBuild>true</ContinuousIntegrationBuild>
   </PropertyGroup>
 
-  <!-- AppVeyor -->
+  <!-- AppVeyor
+  https://www.appveyor.com/docs/environment-variables/
+  -->
   <PropertyGroup Condition="'$(APPVEYOR)' == 'true'">
     <ContinuousIntegrationBuild>true</ContinuousIntegrationBuild>
   </PropertyGroup>
@@ -32,17 +38,23 @@
     <ContinuousIntegrationBuild>true</ContinuousIntegrationBuild>
   </PropertyGroup>
 
-  <!-- Travis CI -->
+  <!-- Travis CI
+  https://docs.travis-ci.com/user/environment-variables/#default-environment-variables
+  -->
   <PropertyGroup Condition="'$(TRAVIS)' == 'true'">
     <ContinuousIntegrationBuild>true</ContinuousIntegrationBuild>
   </PropertyGroup>
 
-  <!-- Circle CI -->
+  <!-- Circle CI
+  https://circleci.com/docs/variables/#built-in-environment-variables
+  -->
   <PropertyGroup Condition="'$(CIRCLECI)' == 'true'">
     <ContinuousIntegrationBuild>true</ContinuousIntegrationBuild>
   </PropertyGroup>
 
-  <!-- AWS CodeBuild -->
+  <!-- AWS CodeBuild
+  https://docs.aws.amazon.com/codebuild/latest/userguide/build-env-ref-env-vars.html
+  -->
   <PropertyGroup Condition="'$(CODEBUILD_BUILD_ID)' != '' and '$(AWS_REGION)' != '' ">
     <ContinuousIntegrationBuild>true</ContinuousIntegrationBuild>
   </PropertyGroup>

tests/DotNet.ReproducibleBuilds.Tests/ContinuousIntegrationTests.cs

@@ -0,0 +1,65 @@
+using FluentAssertions;
+using Microsoft.Build.Utilities.ProjectCreation;
+
+namespace DotNet.ReproducibleBuilds.Tests;
+
+public class ContinuousIntegrationTests : TestBase
+{
+    private const string ContinuousIntegrationBuild = "ContinuousIntegrationBuild";
+
+    [Theory]
+    [InlineData(null, "")]
+    [InlineData(true, "true")]
+    [InlineData(false, "false")]
+    public void RespectsSetValue(bool? value, string expected)
+    {
+        using EnvironmentVariableSuppressor hostSuppressor = new("TF_BUILD"); // Suppress our own CI provider variables (i.e. Azure DevOps)
+
+        ProjectCreator.Templates
+            .ReproducibleBuildProject(GetRandomFile(".csproj"))
+            .PropertyGroup()
+                .Property(ContinuousIntegrationBuild, value?.ToLowerInvariant())
+            .Project
+            .GetPropertyValue(ContinuousIntegrationBuild)
+            .Should().Be(expected);
+    }
+
+    [Theory]
+    [MemberData(nameof(MemberData))]
+    public void RespectsGlobalProperites(Dictionary<string, string> envVars)
+    {
+        using EnvironmentVariableSuppressor hostSuppressor = new("TF_BUILD"); // Suppress our own CI provider variables (i.e. Azure DevOps)
+
+        // If ContinuousIntegrationBuild is not set, it should be set from the CI provider property
+        ProjectCreator.Templates
+            .ReproducibleBuildProject(GetRandomFile(".csproj"))
+            .ProjectWithGlobalProperties(envVars)
+            .GetPropertyValue(ContinuousIntegrationBuild)
+            .Should().Be(true.ToLowerInvariant());
+
+        // If ContinuousIntegrationBuild is set, it should take precedence over the CI provider variables
+        ProjectCreator.Templates
+            .ReproducibleBuildProject(GetRandomFile(".csproj"))
+            .ProjectWithGlobalProperties(envVars.With(ContinuousIntegrationBuild, false.ToLowerInvariant()))
+            .GetPropertyValue(ContinuousIntegrationBuild)
+            .Should().Be(false.ToLowerInvariant(), "because explicitly setting `ContinuousIntegrationBuild` should always win.");
+    }
+
+    public static TheoryData<Dictionary<string, string>> MemberData()
+    {
+        return new TheoryData<Dictionary<string, string>>
+        {
+            { new() { ["TF_BUILD"] = "True" } },
+            { new() { ["GITHUB_ACTIONS"] = "true" } },
+            { new() { ["APPVEYOR"] = "True" } },
+            { new() { ["CI"] = "true" } },
+            { new() { ["TRAVIS"] = "true" } },
+            { new() { ["CIRCLECI"] = "true" } },
+            { new() { ["CODEBUILD_BUILD_ID"] = "abc:123", ["AWS_REGION"] = "us-east-1" } },
+            { new() { ["BUILD_ID"] = "123", ["BUILD_URL"] = "https://buildserver.invalid/jenkins/job/MyJobName/123/" } },
+            { new() { ["BUILD_ID"] = "123", ["PROJECT_ID"] = "234" } },
+            { new() { ["TEAMCITY_VERSION"] = "10" } },
+            { new() { ["JB_SPACE_API_URL"] = "https://api.invalid/url" } },
+        };
+    }
+}

tests/DotNet.ReproducibleBuilds.Tests/DictionaryExtensions.cs

@@ -0,0 +1,7 @@
+namespace DotNet.ReproducibleBuilds.Tests;
+
+internal static class DictionaryExtensions
+{
+    public static IDictionary<TKey, TValue> With<TKey, TValue>(this IDictionary<TKey, TValue> dictionary, TKey key, TValue value) where TKey : notnull
+        => new Dictionary<TKey, TValue>(dictionary) { [key] = value };
+}

tests/DotNet.ReproducibleBuilds.Tests/ProjectCreatorExtensions.cs

@@ -0,0 +1,14 @@
+using Microsoft.Build.Evaluation;
+using Microsoft.Build.Utilities.ProjectCreation;
+
+namespace DotNet.ReproducibleBuilds.Tests;
+
+internal static class ProjectCreatorExtensions
+{
+    public static Project ProjectWithGlobalProperties(this ProjectCreator creator, IDictionary<string, string> properties)
+    {
+        creator.TryGetProject(out Project project, properties);
+
+        return project;
+    }
+}