Straighten the building of some test paths

LibGit2Sharp.Tests/IndexFixture.cs

@@ -175,7 +175,7 @@ namespace LibGit2Sharp.Tests
             {
                 int count = repo.Index.Count;
 
-                string filename = "1" + Path.DirectorySeparatorChar + "branch_file.txt";
+                string filename = Path.Combine("1", "branch_file.txt");
                 const string posixifiedFileName = "1/branch_file.txt";
                 ObjectId blobId = repo.Index[posixifiedFileName].Id;
 
@@ -188,6 +188,7 @@ namespace LibGit2Sharp.Tests
                 Assert.NotEqual((blobId), repo.Index[posixifiedFileName].Id);
 
                 repo.Index.Unstage(posixifiedFileName);
+
                 Assert.Equal(count, repo.Index.Count);
                 Assert.Equal(blobId, repo.Index[posixifiedFileName].Id);
             }
@@ -250,7 +251,7 @@ namespace LibGit2Sharp.Tests
                 int count = repo.Index.Count;
 
                 DirectoryInfo di = Directory.CreateDirectory(Path.Combine(repo.Info.WorkingDirectory, "Project"));
-                string file = "Project" + Path.DirectorySeparatorChar + "a_file.txt";
+                string file = Path.Combine("Project", "a_file.txt");
 
                 File.WriteAllText(Path.Combine(di.FullName, "a_file.txt"), "With backward slash on Windows!");
 

LibGit2Sharp.Tests/ResetIndexFixture.cs

@@ -78,7 +78,7 @@ namespace LibGit2Sharp.Tests
 
                 RepositoryStatus newStatus = repo.Index.RetrieveStatus();
 
-                var expected = new[] { "1.txt", "1" + Path.DirectorySeparatorChar + "branch_file.txt", "deleted_staged_file.txt", 
+                var expected = new[] { "1.txt", Path.Combine("1", "branch_file.txt"), "deleted_staged_file.txt", 
                     "deleted_unstaged_file.txt", "modified_staged_file.txt", "modified_unstaged_file.txt" };
 
                 Assert.Equal(expected.Length, newStatus.Where(IsStaged).Count());

LibGit2Sharp.Tests/StatusFixture.cs

@@ -120,8 +120,7 @@ namespace LibGit2Sharp.Tests
                 Assert.Equal(1, repoStatus.Count());
                 StatusEntry statusEntry = repoStatus.Single();
 
-                string expectedPath = string.Format("{0}{1}{2}", directoryName, Path.DirectorySeparatorChar, fileName);
+                Assert.Equal(Path.Combine(directoryName, fileName), statusEntry.FilePath);
-                Assert.Equal(expectedPath, statusEntry.FilePath);
 
                 Assert.Equal(statusEntry.FilePath, repoStatus.Added.Single());
             }

LibGit2Sharp.Tests/TreeFixture.cs

@@ -154,7 +154,7 @@ namespace LibGit2Sharp.Tests
                 TreeEntry treeTreeEntry = commitTree["1"];
                 Assert.Equal("1", treeTreeEntry.Path);
 
-                string completePath = "1" + Path.DirectorySeparatorChar + "branch_file.txt";
+                string completePath = Path.Combine("1", "branch_file.txt");
 
                 TreeEntry blobTreeEntry = commitTree["1/branch_file.txt"];
                 Assert.Equal(completePath, blobTreeEntry.Path);