added tests, doc and other minor changes

docs/source/developers/contents.rst

@@ -59,6 +59,10 @@ Models may contain the following entries:
 |                    | ``None``   | if any.  (:ref:`See           |
 |                    |            | Below<modelcontent>`)         |
 +--------------------+------------+-------------------------------+
+| **item_count**     | int or     | The number of items in a      |
+|                    | ``None``   | directory, or ``None`` for    |
+|                    |            | files and notebooks.          |
++--------------------+------------+-------------------------------+
 | **format**         | unicode or | The format of ``content``,    |
 |                    | ``None``   | if any. (:ref:`See            |
 |                    |            | Below<modelcontent>`)         |
@@ -110,6 +114,7 @@ model. There are three model types: **notebook**, **file**, and **directory**.
     - The ``content`` field contains a list of :ref:`content-free<contentfree>`
       models representing the entities in the directory.
     - The ``hash`` field is always ``None``.
+    - The ``item_count`` field contains the number of items in the directory
 
 .. note::
 

jupyter_server/services/contents/filemanager.py

@@ -272,6 +272,7 @@ def _base_model(self, path):
         model["writable"] = self.is_writable(path)
         model["hash"] = None
         model["hash_algorithm"] = None
+        model["item_count"] = None
 
         return model
 
@@ -293,12 +294,18 @@ def _dir_model(self, path, content=True):
         model = self._base_model(path)
         model["type"] = "directory"
         model["size"] = None
-        model["item_count"] = None
+        os_dir = self._get_os_path(path)
+        dir_contents = os.listdir(os_dir)
+        model["item_count"] = len(
+            [
+                name
+                for name in dir_contents
+                if self.should_list(name)
+                and (self.allow_hidden or not is_file_hidden(os.path.join(os_dir, name)))
+            ]
+        )
         if content:
             model["content"] = contents = []
-            os_dir = self._get_os_path(path)
-            dir_contents = os.listdir(os_dir)
-            model["item_count"] = len(dir_contents)
             for name in os.listdir(os_dir):
                 try:
                     os_path = os.path.join(os_dir, name)
@@ -768,12 +775,18 @@ async def _dir_model(self, path, content=True):
         model = self._base_model(path)
         model["type"] = "directory"
         model["size"] = None
-        model["item_count"] = None
+        os_dir = self._get_os_path(path)
+        dir_contents = await run_sync(os.listdir, os_dir)
+        model["item_count"] = len(
+            [
+                name
+                for name in dir_contents
+                if self.should_list(name)
+                and (self.allow_hidden or not is_file_hidden(os.path.join(os_dir, name)))
+            ]
+        )
         if content:
             model["content"] = contents = []
-            os_dir = self._get_os_path(path)
-            dir_contents = await run_sync(os.listdir, os_dir)
-            model["item_count"] = len(dir_contents)
             for name in dir_contents:
                 try:
                     os_path = os.path.join(os_dir, name)

tests/services/contents/test_manager.py

@@ -590,6 +590,7 @@ async def test_get(jp_contents_manager):
     assert isinstance(model2, dict)
     assert "name" in model2
     assert "path" in model2
+    assert "item_count" in model2
     assert "content" in model2
     assert model2["name"] == "Untitled.ipynb"
     assert model2["path"] == "{}/{}".format(sub_dir.strip("/"), name)
@@ -631,6 +632,7 @@ async def test_get(jp_contents_manager):
     for key, value in expected_model.items():
         assert file_model[key] == value
     assert "created" in file_model
+    assert "item_count" in file_model
     assert "last_modified" in file_model
     assert file_model["hash"]
 
@@ -639,8 +641,10 @@ async def test_get(jp_contents_manager):
     _make_dir(cm, "foo/bar")
     dirmodel = await ensure_async(cm.get("foo"))
     assert dirmodel["type"] == "directory"
+    assert "item_count" in dirmodel
     assert isinstance(dirmodel["content"], list)
     assert len(dirmodel["content"]) == 3
+    assert dirmodel["item_count"] == 3
     assert dirmodel["path"] == "foo"
     assert dirmodel["name"] == "foo"
 
@@ -649,6 +653,7 @@ async def test_get(jp_contents_manager):
     model2_no_content = await ensure_async(cm.get(sub_dir + name, content=False))
     file_model_no_content = await ensure_async(cm.get("foo/untitled.txt", content=False))
     sub_sub_dir_no_content = await ensure_async(cm.get("foo/bar", content=False))
+    assert "item_count" in model2_no_content
     assert sub_sub_dir_no_content["path"] == "foo/bar"
     assert sub_sub_dir_no_content["name"] == "bar"