Walk parents for .git dir in Task

GitVersionTask.Tests/GitVersionTask.Tests.csproj

@@ -101,6 +101,7 @@
     <Compile Include="ApprovalTestsConfig.cs" />
     <Compile Include="AssemblyInfoBuilderTests.cs" />
     <Compile Include="AssemblyLocation.cs" />
+    <Compile Include="GitVersionTaskDirectoryTests.cs" />
     <Compile Include="Mocks\MockBuildEngine.cs" />
     <Compile Include="GetVersionTaskTests.cs" />
     <Compile Include="Helpers\IPostTestDirectoryRemover.cs" />

GitVersionTask.Tests/GitVersionTaskDirectoryTests.cs

@@ -0,0 +1,61 @@
+using System;
+using System.IO;
+using LibGit2Sharp;
+using NUnit.Framework;
+
+[TestFixture]
+public class GitVersionTaskDirectoryTests
+{
+    string workDirectory;
+    string gitDirectory;
+
+    [SetUp]
+    public void CreateTemporaryRepository()
+    {
+        workDirectory = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
+
+        gitDirectory = Repository.Init(workDirectory)
+                        .TrimEnd(new[] { Path.DirectorySeparatorChar });
+
+        Assert.NotNull(gitDirectory);
+    }
+
+    [TearDown]
+    public void Cleanup()
+    {
+        Directory.Delete(workDirectory, true);
+    }
+
+    [Test]
+    public void Finds_GitDirectory()
+    {
+        try
+        {
+            VersionAndBranchFinder.GetVersion(workDirectory, null, true, null);
+        }
+        catch (Exception ex)
+        {
+            // `RepositoryNotFoundException` means that it couldn't find the .git directory,
+            // any other exception means that the .git was found but there was some other issue that this test doesn't care about.
+            Assert.IsNotAssignableFrom<RepositoryNotFoundException>(ex);
+        }
+    }
+
+    [Test]
+    public void Finds_GitDirectory_In_Parent()
+    {
+        var childDir = Path.Combine(workDirectory, "child");
+        Directory.CreateDirectory(childDir);
+
+        try
+        {
+            VersionAndBranchFinder.GetVersion(childDir, null, true, null);
+        }
+        catch (Exception ex)
+        {
+            // `RepositoryNotFoundException` means that it couldn't find the .git directory,
+            // any other exception means that the .git was found but there was some other issue that this test doesn't care about.
+            Assert.IsNotAssignableFrom<RepositoryNotFoundException>(ex);
+        }
+    }
+}

GitVersionTask/VersionAndBranchFinder.cs

@@ -24,7 +24,8 @@ public static bool TryGetVersion(string directory, out VersionVariables versionV
 
     public static VersionVariables GetVersion(string directory, Authentication authentication, bool noFetch, IFileSystem fileSystem)
     {
-        using (var repo = RepositoryLoader.GetRepo(directory))
+        var gitDir = GitDirFinder.TreeWalkForDotGitDir(directory);
+        using (var repo = RepositoryLoader.GetRepo(gitDir))
         {
             var ticks = DirectoryDateFinder.GetLastDirectoryWrite(directory);
             var key = string.Format("{0}:{1}:{2}", repo.Head.CanonicalName, repo.Head.Tip.Sha, ticks);