Repository: add ctor for in-memory repo

Author: Edward Thomson

LibGit2Sharp.Tests/RepositoryFixture.cs

@@ -652,5 +652,18 @@ public void CanDetectShallowness()
                 Assert.False(repo.Info.IsShallow);
             }
         }
+
+        [Fact]
+        public void CanCreateInMemoryRepository()
+        {
+            using (var repo = new Repository())
+            {
+                Assert.True(repo.Info.IsBare);
+                Assert.Null(repo.Info.Path);
+                Assert.Null(repo.Info.WorkingDirectory);
+
+                Assert.Throws<BareRepositoryException>(() => { var idx = repo.Index; });
+            }
+        }
     }
 }

LibGit2Sharp/Core/NativeMethods.cs

@@ -1193,6 +1193,10 @@ internal static extern int git_repository_message(
             GitBuf buf,
             RepositorySafeHandle repository);
 
+        [DllImport(libgit2)]
+        internal static extern int git_repository_new(
+            out RepositorySafeHandle repository);
+
         [DllImport(libgit2)]
         internal static extern int git_repository_odb(out ObjectDatabaseSafeHandle odb, RepositorySafeHandle repo);
 

LibGit2Sharp/Core/Proxy.cs

@@ -2345,6 +2345,19 @@ public static string git_repository_message(RepositorySafeHandle repo)
             }
         }
 
+        public static RepositorySafeHandle git_repository_new()
+        {
+            using (ThreadAffinity())
+            {
+                RepositorySafeHandle repo;
+
+                int res = NativeMethods.git_repository_new(out repo);
+                Ensure.ZeroResult(res);
+
+                return repo;
+            }
+        }
+
         public static ObjectDatabaseSafeHandle git_repository_odb(RepositorySafeHandle repo)
         {
             using (ThreadAffinity())

LibGit2Sharp/Repository.cs

@@ -37,6 +37,25 @@ public sealed class Repository : IRepository
         private readonly SubmoduleCollection submodules;
         private readonly Lazy<PathCase> pathCase;
 
+        private enum RepositoryRequiredParameter
+        {
+            None = 0,
+            Path = 1,
+            Options = 2,
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Repository"/> class
+        /// that does not point to an on-disk Git repository.  This is
+        /// suitable only for custom, in-memory Git repositories that are
+        /// configured with custom object database, reference database and/or
+        /// configuration backends.
+        /// </summary>
+        public Repository()
+            : this(null, null, RepositoryRequiredParameter.None)
+        {
+        }
+
         /// <summary>
         /// Initializes a new instance of the <see cref="Repository"/> class.
         /// <para>For a standard repository, <paramref name="path"/> may
@@ -51,7 +70,7 @@ public sealed class Repository : IRepository
         /// or the path to the working directory.
         /// </param>
         public Repository(string path) :
-            this(path, null)
+            this(path, null, RepositoryRequiredParameter.Path)
         {
         }
 
@@ -73,9 +92,22 @@ public Repository(string path) :
         /// <param name="options">
         /// Overrides to the way a repository is opened.
         /// </param>
-        public Repository(string path, RepositoryOptions options)
+        public Repository(string path, RepositoryOptions options) :
+            this(path, options, RepositoryRequiredParameter.Path | RepositoryRequiredParameter.Options)
         {
-            Ensure.ArgumentNotNullOrEmptyString(path, "path");
+        }
+
+        private Repository(string path, RepositoryOptions options, RepositoryRequiredParameter requiredParameter)
+        {
+            if ((requiredParameter & RepositoryRequiredParameter.Path) == RepositoryRequiredParameter.Path)
+            {
+                Ensure.ArgumentNotNullOrEmptyString(path, "path");
+            }
+
+            if ((requiredParameter & RepositoryRequiredParameter.Options) == RepositoryRequiredParameter.Options)
+            {
+                Ensure.ArgumentNotNull(options, "options");
+            }
 
             try
             {
@@ -84,6 +116,14 @@ public Repository(string path, RepositoryOptions options)
 
                 isBare = Proxy.git_repository_is_bare(handle);
 
+                /* TODO: bug in libgit2, update when fixed by
+                 * https://github.com/libgit2/libgit2/pull/2970
+                 */
+                if (path == null)
+                {
+                    isBare = true;
+                }
+
                 Func<Index> indexBuilder = () => new Index(this);
 
                 string configurationGlobalFilePath = null;
@@ -764,7 +804,7 @@ private void CheckoutTree(
             IConvertableToGitCheckoutOpts opts)
         {
 
-            using (GitCheckoutOptsWrapper checkoutOptionsWrapper = new GitCheckoutOptsWrapper(opts, ToFilePaths(paths)))
+            using(GitCheckoutOptsWrapper checkoutOptionsWrapper = new GitCheckoutOptsWrapper(opts, ToFilePaths(paths)))
             {
                 var options = checkoutOptionsWrapper.Options;
                 Proxy.git_checkout_tree(Handle, tree.Id, ref options);
@@ -935,7 +975,7 @@ private void UpdateHeadAndTerminalReference(Commit commit, string reflogMessage)
                     return;
                 }
 
-                var symRef = (SymbolicReference)reference;
+                var symRef = (SymbolicReference) reference;
 
                 reference = symRef.Target;
 
@@ -1294,7 +1334,7 @@ private MergeResult Merge(GitAnnotatedCommitHandle[] annotatedCommits, Signature
             FastForwardStrategy fastForwardStrategy = (options.FastForwardStrategy != FastForwardStrategy.Default) ?
                 options.FastForwardStrategy : FastForwardStrategyFromMergePreference(mergePreference);
 
-            switch (fastForwardStrategy)
+            switch(fastForwardStrategy)
             {
                 case FastForwardStrategy.Default:
                     if (mergeAnalysis.HasFlag(GitMergeAnalysis.GIT_MERGE_ANALYSIS_FASTFORWARD))
@@ -1362,14 +1402,14 @@ private MergeResult NormalMerge(GitAnnotatedCommitHandle[] annotatedCommits, Sig
             MergeResult mergeResult;
 
             var mergeOptions = new GitMergeOpts
-            {
-                Version = 1,
-                MergeFileFavorFlags = options.MergeFileFavor,
-                MergeTreeFlags = options.FindRenames ? GitMergeTreeFlags.GIT_MERGE_TREE_FIND_RENAMES :
-                                                       GitMergeTreeFlags.GIT_MERGE_TREE_NORMAL,
-                RenameThreshold = (uint)options.RenameThreshold,
-                TargetLimit = (uint)options.TargetLimit,
-            };
+                {
+                    Version = 1,
+                    MergeFileFavorFlags = options.MergeFileFavor,
+                    MergeTreeFlags = options.FindRenames ? GitMergeTreeFlags.GIT_MERGE_TREE_FIND_RENAMES :
+                                                           GitMergeTreeFlags.GIT_MERGE_TREE_NORMAL,
+                    RenameThreshold = (uint) options.RenameThreshold,
+                    TargetLimit = (uint) options.TargetLimit,
+                };
 
             using (GitCheckoutOptsWrapper checkoutOptionsWrapper = new GitCheckoutOptsWrapper(options))
             {
@@ -1407,7 +1447,7 @@ private MergeResult NormalMerge(GitAnnotatedCommitHandle[] annotatedCommits, Sig
         private MergeResult FastForwardMerge(GitAnnotatedCommitHandle annotatedCommit, Signature merger, MergeOptions options)
         {
             ObjectId id = Proxy.git_annotated_commit_id(annotatedCommit);
-            Commit fastForwardCommit = (Commit)Lookup(id, ObjectType.Commit);
+            Commit fastForwardCommit = (Commit) Lookup(id, ObjectType.Commit);
             Ensure.GitObjectIsNotNull(fastForwardCommit, id.Sha);
 
             CheckoutTree(fastForwardCommit.Tree, null, new FastForwardCheckoutOptionsAdapter(options));
@@ -1882,7 +1922,7 @@ private IEnumerable<string> RemoveStagedItems(IEnumerable<string> paths, bool re
                     case ChangeKind.Unmodified:
                         if (removeFromWorkingDirectory && (
                             status.HasFlag(FileStatus.Staged) ||
-                            status.HasFlag(FileStatus.Added)))
+                            status.HasFlag(FileStatus.Added) ))
                         {
                             throw new RemoveFromIndexException(string.Format(CultureInfo.InvariantCulture, "Unable to remove file '{0}', as it has changes staged in the index. You can call the Remove() method with removeFromWorkingDirectory=false if you want to remove it from the index only.",
                                 treeEntryChanges.Path));

LibGit2Sharp/RepositoryInformation.cs

@@ -24,7 +24,7 @@ internal RepositoryInformation(Repository repo, bool isBare)
             FilePath path = Proxy.git_repository_path(repo.Handle);
             FilePath workingDirectoryPath = Proxy.git_repository_workdir(repo.Handle);
 
-            Path = path.Native;
+            Path = path == null ? null : path.Native;
             WorkingDirectory = workingDirectoryPath == null ? null : workingDirectoryPath.Native;
             IsShallow = Proxy.git_repository_is_shallow(repo.Handle);
         }