List empty dirs in gl status

So users can track them if they wish.

Author: embs

gitless/core.py

@@ -771,6 +771,14 @@ def status(self):
         yield self.FileStatus(
             fp, GL_STATUS_UNTRACKED, True, exists_in_wd, True, False)
 
+    # find untracked empty dirs
+    for dirpath, dirs, files in os.walk('.', topdown=True):
+      dirs[:] = [d for d in dirs if d not in ['.git'] and not
+          self.path_is_ignored(d)]
+      if not dirs and not files:
+        yield self.FileStatus(dirpath, GL_STATUS_UNTRACKED, False, True, False,
+            False)
+
   def status_file(self, path):
     """Return the status (see FileStatus) of the given path."""
     return self._status_file(path)[0]

gitless/tests/test_e2e.py

@@ -685,17 +685,35 @@ def test_uncommitted_tracked_changes_that_conflict_append(self):
 
 class TestEmptyDir(TestEndToEnd):
 
+  def test_empty_dir_status(self):
+    untracked_empty_dir = self._mk_empty_dir('untracked_empty_dir')
+
+    out = utils.stdout(gl.status())
+
+    self.assertIn(untracked_empty_dir, out, 'Empty dir didn\'t appear in status')
+
+  def test_ignored_empty_dir_status(self):
+    ignored_empty_dir = self._mk_empty_dir('ignored_empty_dir')
+    utils.write_file(os.path.join(self.path, '.gitignore'), ignored_empty_dir)
+
+    out = utils.stdout(gl.status())
+
+    self.assertFalse(ignored_empty_dir in out,
+        'Ignored empty dir was listed in status')
+
   def test_track_empty_dir(self):
-    dir_to_track = 'wanted_empty_dir'
-    dir_to_track_path = os.path.join(self.path, dir_to_track)
-    os.mkdir(dir_to_track_path)
+    dir_to_track = self._mk_empty_dir('wanted_empty_dir')
     expected_out = 'Empty directory {0} is now a tracked directory'.format(
       os.path.join(dir_to_track, ''))
 
-    out = utils.stdout(gl.track(dir_to_track_path))
+    out = utils.stdout(gl.track(dir_to_track))
 
     self.assertIn(expected_out, out, 'Empty dir wasn\'t tracked')
 
+  def _mk_empty_dir(self, name):
+    os.mkdir(os.path.join(self.path, name))
+    return name
+
 
 class TestPerformance(TestEndToEnd):