get branch of commit on detached head

GitVersionCore.Tests/Fixtures/RemoteRepositoryFixture.cs

@@ -0,0 +1,56 @@
+using System;
+
+namespace GitVersionCore.Tests.Fixtures
+{
+    using GitVersion;
+    using LibGit2Sharp;
+
+    public class RemoteRepositoryFixture : RepositoryFixtureBase
+    {
+        public string LocalRepositoryPath;
+        public IRepository LocalRepository;
+
+        public RemoteRepositoryFixture(Config configuration)
+            : base(CreateNewRepository, configuration)
+        {
+
+            CloneRepository();
+        }
+
+
+
+        static IRepository CreateNewRepository(string path)
+        {
+            LibGit2Sharp.Repository.Init(path);
+            Console.WriteLine("Created git repository at '{0}'", path);
+
+            var repo = new Repository(path);
+            repo.MakeCommits(5);
+            return repo;
+        }
+
+
+        void CloneRepository()
+        {
+            LocalRepositoryPath = PathHelper.GetTempPath();
+            LibGit2Sharp.Repository.Clone(RepositoryPath, LocalRepositoryPath);
+            LocalRepository = new Repository(LocalRepositoryPath);
+        }
+
+
+        public override void Dispose()
+        {
+            LocalRepository.Dispose();
+            try
+            {
+                DirectoryHelper.DeleteDirectory(LocalRepositoryPath);
+            }
+            catch (Exception e)
+            {
+                Console.WriteLine("Failed to clean up repository path at {0}. Received exception: {1}", RepositoryPath, e.Message);
+            }
+
+            base.Dispose();
+        }
+    }
+}

GitVersionCore.Tests/Fixtures/RepositoryFixtureBase.cs

@@ -16,20 +16,23 @@ protected RepositoryFixtureBase(Func<string, IRepository> repoBuilder, Config co
         Repository = repoBuilder(RepositoryPath);
         Repository.Config.Set("user.name", "Test");
         Repository.Config.Set("user.email", "[email protected]");
+        IsForTrackedBranchOnly = true;
     }
 
-    public SemanticVersion ExecuteGitVersion()
+    public bool IsForTrackedBranchOnly { private get; set; }
+
+    public SemanticVersion ExecuteGitVersion(IRepository repository = null)
     {
         var vf = new GitVersionFinder();
-        return vf.FindVersion(new GitVersionContext(Repository, configuration));
+        return vf.FindVersion(new GitVersionContext(repository ?? Repository, configuration, IsForTrackedBranchOnly));
     }
 
-    public void AssertFullSemver(string fullSemver)
+    public void AssertFullSemver(string fullSemver, IRepository repository = null)
     {
-        ExecuteGitVersion().ToString("f").ShouldBe(fullSemver);
+        ExecuteGitVersion(repository).ToString("f").ShouldBe(fullSemver);
     }
 
-    public void Dispose()
+    public virtual void Dispose()
     {
         Repository.Dispose();
 

GitVersionCore.Tests/GitVersionCore.Tests.csproj

@@ -71,8 +71,10 @@
     </Compile>
     <Compile Include="Fixtures\CommitCountingRepoFixture.cs" />
     <Compile Include="ConfigProviderTests.cs" />
+    <Compile Include="Fixtures\RemoteRepositoryFixture.cs" />
     <Compile Include="GitDirFinderTests.cs" />
     <Compile Include="Fixtures\BaseGitFlowRepositoryFixture.cs" />
+    <Compile Include="IntegrationTests\RemoteRepositoryTests.cs" />
     <Compile Include="IntegrationTests\GitFlow\DevelopScenarios.cs" />
     <Compile Include="IntegrationTests\GitFlow\SupportBranchScenarios.cs" />
     <Compile Include="IntegrationTests\GitFlow\MetaDataByCommitScenarios.cs" />

GitVersionCore.Tests/IntegrationTests/RemoteRepositoryTests.cs

@@ -0,0 +1,63 @@
+
+namespace GitVersionCore.Tests.IntegrationTests
+{
+    using System;
+    using GitVersion;
+    using GitVersionCore.Tests.Fixtures;
+    using LibGit2Sharp;
+    using NUnit.Framework;
+
+    [TestFixture]
+    public class RemoteRepositoryTests
+    {
+        [Test]
+        public void GivenARemoteGitRepositoryWithCommits_ThenClonedLocalShouldMatchRemoteVersion()
+        {
+            using (var fixture = new RemoteRepositoryFixture(new Config()))
+            {
+                fixture.AssertFullSemver("0.1.0+4");
+                fixture.AssertFullSemver("0.1.0+4", fixture.LocalRepository);
+            }
+        }
+
+        [Test]
+        public void GivenARemoteGitRepositoryAheadOfLocalRepository_ThenChangesShouldPull()
+        {
+            using (var fixture = new RemoteRepositoryFixture(new Config()))
+            {
+                fixture.Repository.MakeACommit();
+                fixture.AssertFullSemver("0.1.0+5");
+                fixture.AssertFullSemver("0.1.0+4", fixture.LocalRepository);
+                fixture.LocalRepository.Network.Pull(fixture.LocalRepository.Config.BuildSignature(new DateTimeOffset(DateTime.Now)), new PullOptions());
+                fixture.AssertFullSemver("0.1.0+5", fixture.LocalRepository);
+            }
+        }
+
+        [Test]
+        public void GivenARemoteGitRepositoryWhenCheckingOutDetachedhead_UsingExistingImplemenationThrowsException()
+        {
+
+            using (var fixture = new RemoteRepositoryFixture(new Config()))
+            {
+                fixture.IsForTrackedBranchOnly = false;
+                fixture.LocalRepository.Checkout(fixture.LocalRepository.Head.Tip);
+
+                Assert.Throws<WarningException>(() => fixture.AssertFullSemver("0.1.0+4", fixture.LocalRepository), "It looks like the branch being examined is a detached Head pointing to commit '{0}'. Without a proper branch name GitVersion cannot determine the build version.", fixture.LocalRepository.Head.Tip.Id.ToString(7));
+            }
+        }
+
+        [Test]
+        public void GivenARemoteGitRepositoryWhenCheckingOutDetachedhead_UsingTrackingBranchOnlyBehaviourShouldReturnVersion_0_1_4plus5()
+        {
+
+            using (var fixture = new RemoteRepositoryFixture(new Config()))
+            {
+
+                fixture.LocalRepository.Checkout(fixture.LocalRepository.Head.Tip);
+
+                fixture.AssertFullSemver("0.1.0+4", fixture.LocalRepository);
+            }
+        }
+    }
+
+}

GitVersionCore/GitVersionContext.cs

@@ -9,16 +9,17 @@
     /// </summary>
     public class GitVersionContext
     {
-        public GitVersionContext(IRepository repository, Config configuration)
-            : this(repository, repository.Head, configuration)
+        public GitVersionContext(IRepository repository, Config configuration, bool isForTrackingBranchOnly = true)
+            : this(repository, repository.Head, configuration, isForTrackingBranchOnly)
         {
             Configuration = configuration;
         }
 
-        public GitVersionContext(IRepository repository, Branch currentBranch, Config configuration)
+        public GitVersionContext(IRepository repository, Branch currentBranch, Config configuration, bool isForTrackingBranchOnly = true)
         {
             Repository = repository;
             Configuration = configuration;
+            IsContextForTrackedBranchesOnly = isForTrackingBranchOnly;
 
             if (currentBranch == null)
                 return;
@@ -40,12 +41,15 @@ public GitVersionContext(IRepository repository, Branch currentBranch, Config co
         public Branch CurrentBranch { get; private set; }
         public Commit CurrentCommit { get; private set; }
 
+        readonly bool IsContextForTrackedBranchesOnly = true;
+
+
         IEnumerable<Branch> GetBranchesContainingCommit(string commitSha)
         {
             var directBranchHasBeenFound = false;
             foreach (var branch in Repository.Branches)
             {
-                if (branch.Tip.Sha != commitSha)
+                if (branch.Tip.Sha != commitSha || (IsContextForTrackedBranchesOnly && !branch.IsTracking))
                 {
                     continue;
                 }