Teach BranchCollection to disambiguate local and remote branch names

Author: jamill

LibGit2Sharp.Tests/BranchFixture.cs

@@ -189,6 +189,27 @@ public void CanListAllBranches()
             }
         }
 
+        [Fact]
+        public void CanListBranchesWithRemoteAndLocalBranchWithSameShortName()
+        {
+            TemporaryCloneOfTestRepo path = BuildTemporaryCloneOfTestRepo(StandardTestRepoWorkingDirPath);
+
+            using (var repo = new Repository(path.RepositoryPath))
+            {
+                // Create a local branch with the same short name as a remote branch.
+                repo.Branches.Add("origin/master", repo.Branches["origin/test"].Tip);
+
+                var expectedWdBranches = new[]
+                                             {
+                                                 "diff-test-cases", "i-do-numbers", "logo", "master", "origin/master", "track-local",
+                                             };
+
+                Assert.Equal(expectedWdBranches, repo.Branches
+                    .Where(b => !b.IsRemote)
+                    .Select(b => b.Name).ToArray());
+            }
+        }
+
         [Fact]
         public void CanListAllBranchesWhenGivenWorkingDir()
         {

LibGit2Sharp/BranchCollection.cs

@@ -91,7 +91,7 @@ private Branch BuildFromReferenceName(string canonicalName)
         /// <returns>An <see cref = "IEnumerator{T}" /> object that can be used to iterate through the collection.</returns>
         public virtual IEnumerator<Branch> GetEnumerator()
         {
-            return Proxy.git_branch_foreach(repo.Handle, GitBranchType.GIT_BRANCH_LOCAL | GitBranchType.GIT_BRANCH_REMOTE, (b, t) => Utf8Marshaler.FromNative(b))
+            return Proxy.git_branch_foreach(repo.Handle, GitBranchType.GIT_BRANCH_LOCAL | GitBranchType.GIT_BRANCH_REMOTE, branchToCanoncialName)
                 .Select(n => this[n])
                 .OrderBy(b => b.CanonicalName, StringComparer.Ordinal)
                 .GetEnumerator();
@@ -197,6 +197,21 @@ private static bool LooksLikeABranchName(string referenceName)
                 referenceName.StartsWith("refs/remotes/", StringComparison.Ordinal);
         }
 
+        private static string branchToCanoncialName(IntPtr namePtr, GitBranchType branchType)
+        {
+            string shortName = Utf8Marshaler.FromNative(namePtr);
+
+            switch (branchType)
+            {
+                case GitBranchType.GIT_BRANCH_LOCAL:
+                    return ShortToLocalName(shortName);
+                case GitBranchType.GIT_BRANCH_REMOTE:
+                    return ShortToRemoteName(shortName);
+                default:
+                    return shortName;
+            }
+        }
+
         private string DebuggerDisplay
         {
             get