Added some infrastructure for running isolated tests which modify the content of a git repository.

libgit2sharp.Tests/InstantiatingARepository.cs

@@ -5,10 +5,8 @@
 namespace libgit2sharp.Tests
 {
     [TestFixture]
-    public class InstantiatingARepository
+    public class InstantiatingARepository : ReadOnlyRepositoryFixtureBase
     {
-        const string PathToRepository = "../../Resources/testrepo.git";
-
         [Test]
         public void ShouldThrowIfPassedANonValidGitDirectory()
         {

libgit2sharp.Tests/ReadOnlyRepositoryFixtureBase.cs

+namespace libgit2sharp.Tests
+{
+    public class ReadOnlyRepositoryFixtureBase
+    {
+        protected virtual string PathToRepository  { get { return "../../Resources/testrepo.git"; } }
+    }
+}
\ No newline at end of file

libgit2sharp.Tests/ReadWriteRepositoryFixtureBase.cs

+using System;
+using System.IO;
+using System.Reflection;
+using NUnit.Framework;
+
+namespace libgit2sharp.Tests
+{
+    public class ReadWriteRepositoryFixtureBase : ReadOnlyRepositoryFixtureBase
+    {
+        private const string TestRepositoriesDirectoryName = "TestRepos";
+        private static readonly string _testRepositoriesDirectoryPath = RetrieveTestRepositoriesDirectory();
+        private string _pathToRepository;
+        
+        protected override string PathToRepository { get { return _pathToRepository; } }
+
+        [SetUp]
+        public void Setup()
+        {
+            // Create temporary working directory
+            string workDirpath = Path.Combine(_testRepositoriesDirectoryPath, this.GetType().Name, Guid.NewGuid().ToString().Substring(0, 8));
+
+            var source = new DirectoryInfo(base.PathToRepository);
+            var tempRepository = new DirectoryInfo(Path.Combine(workDirpath, source.Name));
+
+            CopyFilesRecursively(source, tempRepository);
+
+            _pathToRepository = tempRepository.FullName;
+        }
+
+        [TestFixtureTearDown]
+        public void TestFixtureTearDown()
+        {
+            Directory.Delete(_testRepositoriesDirectoryPath, true);
+        }
+
+        public static void CopyFilesRecursively(DirectoryInfo source, DirectoryInfo target)
+        {
+            // From http://stackoverflow.com/questions/58744/best-way-to-copy-the-entire-contents-of-a-directory-in-c/58779#58779
+
+            foreach (DirectoryInfo dir in source.GetDirectories())
+                CopyFilesRecursively(dir, target.CreateSubdirectory(dir.Name));
+            foreach (FileInfo file in source.GetFiles())
+                file.CopyTo(Path.Combine(target.FullName, file.Name));
+        }
+
+        static private string RetrieveTestRepositoriesDirectory()
+        {
+            return Path.Combine(RetrieveAssemblyDirectory(), TestRepositoriesDirectoryName);
+        }
+
+        static private string RetrieveAssemblyDirectory()
+        {
+            // From http://stackoverflow.com/questions/52797/c-how-do-i-get-the-path-of-the-assembly-the-code-is-in/283917#283917
+
+            string codeBase = Assembly.GetExecutingAssembly().CodeBase;
+            var uri = new UriBuilder(codeBase);
+            string path = Uri.UnescapeDataString(uri.Path);
+            return Path.GetDirectoryName(path);
+        }
+    }
+}
\ No newline at end of file

libgit2sharp.Tests/RepositoryFixtures.cs

@@ -5,10 +5,8 @@
 namespace libgit2sharp.Tests
 {
     [TestFixture]
-    public class RepositoryFixtures
+    public class RepositoryFixtures : ReadOnlyRepositoryFixtureBase
     {
-        const string PathToRepository = "../../Resources/testrepo.git";
-
         [Test]
         public void Ctor_RetrieveDetails()
         {

libgit2sharp.Tests/libgit2sharp.Tests.csproj

@@ -45,6 +45,8 @@
   <ItemGroup>
     <Compile Include="GitDateFixture.cs" />
     <Compile Include="ObjectIdFixture.cs" />
+    <Compile Include="ReadOnlyRepositoryFixtureBase.cs" />
+    <Compile Include="ReadWriteRepositoryFixtureBase.cs" />
     <Compile Include="RepositoryFixtures.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="InstantiatingARepository.cs" />