Enable clone and disable open button on empty dir.

- Currently clone button is disabled and open button is enabled
on empty directories.
- Desired behavior should support cloning to empty directories.
- Non-empty directory message is not shown when the directory is empty.

Author: YuPeiHenry

src/GitHub.App/Services/RepositoryCloneService.cs

@@ -232,6 +232,9 @@ public async Task CloneRepository(
         /// <inheritdoc/>
         public bool DestinationDirectoryExists(string path) => operatingSystem.Directory.DirectoryExists(path);
 
+        /// <inheritdoc/>
+        public bool DestinationDirectoryEmpty(string path) => !DestinationDirectoryExists(path) || operatingSystem.Directory.GetDirectory(path).IsEmpty;
+
         /// <inheritdoc/>
         public bool DestinationFileExists(string path) => operatingSystem.File.Exists(path);
 

src/GitHub.App/ViewModels/Dialog/Clone/RepositoryCloneViewModel.cs

@@ -67,11 +67,13 @@ public RepositoryCloneViewModel(
 
             var canClone = Observable.CombineLatest(
                 repository, this.WhenAnyValue(x => x.Path),
-                (repo, path) => repo != null && !service.DestinationFileExists(path) && !service.DestinationDirectoryExists(path));
+                (repo, path) => repo != null && !service.DestinationFileExists(path) &&
+                (!service.DestinationDirectoryExists(path)) || service.DestinationDirectoryEmpty(path));
 
             var canOpen = Observable.CombineLatest(
                 repository, this.WhenAnyValue(x => x.Path),
-                (repo, path) => repo != null && !service.DestinationFileExists(path) && service.DestinationDirectoryExists(path));
+                (repo, path) => repo != null && !service.DestinationFileExists(path) && service.DestinationDirectoryExists(path)
+                && !service.DestinationDirectoryEmpty(path));
 
             Browse = ReactiveCommand.Create(() => BrowseForDirectory());
             Clone = ReactiveCommand.CreateFromObservable(
@@ -240,6 +242,11 @@ string ValidatePathWarning(RepositoryModel repositoryModel, string path)
                 {
                     using (var repository = gitService.GetRepository(path))
                     {
+                        if (service.DestinationDirectoryEmpty(path))
+                        {
+                            return null;
+                        }
+
                         if (repository == null)
                         {
                             return Resources.CantFindARepositoryAtLocalPath;

src/GitHub.Exports.Reactive/Services/IRepositoryCloneService.cs

@@ -58,6 +58,15 @@ Task CloneOrOpenRepository(
         /// </returns>
         bool DestinationDirectoryExists(string path);
 
+        /// <summary>
+        /// Checks whether the specified destination directory is empty.
+        /// </summary>
+        /// <param name="path">The destination path.</param>
+        /// <returns>
+        /// true if a directory is empty <paramref name="path"/>; otherwise false.
+        /// </returns>
+        bool DestinationDirectoryEmpty(string path);
+
         /// <summary>
         /// Checks whether the specified destination file already exists.
         /// </summary>