Replace ipykernel dependency by the comm dependency

.github/workflows/devinstall.yml

@@ -28,7 +28,7 @@ jobs:
 
       - name: Install dependencies
         run: |
-          python -m pip install notebook jupyterlab jupyter_packaging~=0.10
+          python -m pip install notebook jupyterlab notebook~=6.0 jupyter_packaging~=0.10
       - name: Run the dev-install script
         run: |
           ./dev-install.sh

dev-install.sh

@@ -31,11 +31,11 @@ jlpm build
 echo -n "widgetsnbextension"
 pip install -v -e ./python/widgetsnbextension
 if [[ "$OSTYPE" == "msys" ]]; then
-    jupyter nbextension install --overwrite --py $nbExtFlags widgetsnbextension
+    jupyter nbextension install --overwrite --py $nbExtFlags widgetsnbextension || true
 else
-    jupyter nbextension install --overwrite --py --symlink $nbExtFlags widgetsnbextension
+    jupyter nbextension install --overwrite --py --symlink $nbExtFlags widgetsnbextension || true
 fi
-jupyter nbextension enable --py $nbExtFlags widgetsnbextension
+jupyter nbextension enable --py $nbExtFlags widgetsnbextension || true
 
 echo -n "ipywidgets"
 pip install -v -e "./python/ipywidgets[test]"

docs/source/examples/Widget Custom.ipynb

@@ -3,7 +3,9 @@
   {
    "cell_type": "markdown",
    "metadata": {
-    "tags": ["remove-cell"]
+    "tags": [
+     "remove-cell"
+    ]
    },
    "source": [
     "[Index](Index.ipynb) - [Back](Widget%20Styling.ipynb) - [Next](Widget%20Asynchronous.ipynb)"
@@ -828,7 +830,9 @@
   {
    "cell_type": "markdown",
    "metadata": {
-    "tags": ["remove-cell"]
+    "tags": [
+     "remove-cell"
+    ]
    },
    "source": [
     "[Index](Index.ipynb) - [Back](Widget%20Styling.ipynb) - [Next](Widget%20Asynchronous.ipynb)"

python/ipywidgets/ipywidgets/__init__.py

@@ -21,17 +21,21 @@
 from ._version import __version__, __protocol_version__, __jupyter_widgets_controls_version__, __jupyter_widgets_base_version__
 
 import os
+import sys
 
 from traitlets import link, dlink
 from IPython import get_ipython
-try:
-    from comm import get_comm_manager
-except ImportError:
+
+# ipykernel <6.18 when the comm package did not exist
+if "ipykernel" in sys.modules and "comm" not in sys.modules:
     def get_comm_manager():
         ip = get_ipython()
 
         if ip is not None and getattr(ip, "kernel", None) is not None:
             return get_ipython().kernel.comm_manager
+# Using the comm package
+else:
+    from comm import get_comm_manager
 
 from .widgets import *
 

python/ipywidgets/ipywidgets/tests/test_embed.py

@@ -9,9 +9,6 @@
 
 import traitlets
 
-# This has a byproduct of setting up the comms
-import ipykernel.ipkernel
-
 from ..widgets import IntSlider, IntText, Text, Widget, jslink, HBox, widget_serialization, widget as widget_module
 from ..embed import embed_data, embed_snippet, embed_minimal_html, dependency_state
 

python/ipywidgets/ipywidgets/widgets/widget.py

@@ -6,6 +6,7 @@
 in the Jupyter notebook front-end.
 """
 import os
+import sys
 import typing
 from contextlib import contextmanager
 from collections.abc import Iterable
@@ -524,13 +525,14 @@ def open(self):
             if self._model_id is not None:
                 args['comm_id'] = self._model_id
 
-            try:
-                from comm import create_comm
-            except ImportError:
+            # ipykernel <6.18 when the comm package did not exist
+            if "ipykernel" in sys.modules and "comm" not in sys.modules:
                 def create_comm(**kwargs):
                     from ipykernel.comm import Comm
 
                     return Comm(**kwargs)
+            else:
+                from comm import create_comm
 
             self.comm = create_comm(**args)
 

python/ipywidgets/setup.cfg

@@ -34,7 +34,7 @@ zip_safe = False
 packages = find:
 
 install_requires =
-  ipykernel>=4.5.1
+  comm>=0.1.3
   ipython>=6.1.0
   traitlets>=4.3.1
   widgetsnbextension~=4.0.7