feat(repository): add ability to set working directory

lib/src/bindings/repository.dart

@@ -349,7 +349,7 @@ void setHeadDetachedFromAnnotated(
   }
 }
 
-/// Set the path to the working directory for this repository
+/// Set the path to the working directory for this repository.
 ///
 /// The working directory doesn't need to be the same one that contains the
 /// `.git` folder for this repository.

lib/src/repository.dart

@@ -167,6 +167,20 @@ class Repository {
   /// If the repository is bare, this function will always return empty string.
   String get workdir => bindings.workdir(_repoPointer);
 
+  /// Sets the path to the working directory for this repository.
+  ///
+  /// The working directory doesn't need to be the same one that contains the
+  /// `.git` folder for this repository.
+  ///
+  /// If this repository is bare, setting its working directory will turn it into a
+  /// normal repository, capable of performing all the common workdir operations
+  /// (checkout, status, index manipulation, etc).
+  ///
+  /// Throws a [LibGit2Error] if error occured.
+  void setWorkdir(String path, [bool updateGitlink = false]) {
+    bindings.setWorkdir(_repoPointer, path, updateGitlink);
+  }
+
   /// Releases memory allocated for repository object.
   void free() {
     bindings.free(_repoPointer);

test/repository_test.dart

@@ -154,6 +154,16 @@ void main() {
         expect(repo.namespace, '');
       });
 
+      test('successfully sets working directory', () {
+        final tmpWorkDir = '${Directory.systemTemp.path}/tmp_work_dir/';
+        Directory(tmpWorkDir).createSync();
+
+        repo.setWorkdir(tmpWorkDir);
+        expect(repo.workdir, tmpWorkDir);
+
+        Directory(tmpWorkDir).deleteSync();
+      });
+
       group('setHead', () {
         test('successfully sets head when target is reference', () {
           expect(repo.head.name, 'refs/heads/master');