Ignore output messages from comm_msg

src/kernels/execution/cellExecutionMessageHandler.ts

@@ -627,6 +627,12 @@ export class CellExecutionMessageHandler implements IDisposable {
                 CellExecutionMessageHandler.modelIdsOwnedByCells.set(this.cell, modelIds);
             }
         }
+        if (originalMessage.parent_header.msg_type === 'comm_msg') {
+            // Outputs generated as part of a comm message are not displayed in the cell output.
+            // See https://github.com/microsoft/vscode-jupyter/issues/15996
+            return;
+        }
+
         const cellOutput = cellOutputToVSCCellOutput(output);
         const displayId =
             'transient' in output &&
@@ -946,6 +952,11 @@ export class CellExecutionMessageHandler implements IDisposable {
             // Stream messages will be handled by the Output Widget.
             return;
         }
+        if (msg.parent_header.msg_type === 'comm_msg') {
+            // Outputs generated as part of a comm message are not displayed in the cell output.
+            // See https://github.com/microsoft/vscode-jupyter/issues/15996
+            return;
+        }
 
         // eslint-disable-next-line complexity
         traceCellMessage(this.cell, `Update streamed output, new output '${msg.content.text.substring(0, 100)}'`);

src/test/datascience/widgets/notebooks/button_widget_comm_msg_matplotlib.ipynb

@@ -7,23 +7,26 @@
    "outputs": [],
    "source": [
     "%matplotlib widget\n",
-    "from IPython.display import display\n",
     "from ipywidgets import widgets\n",
     "import matplotlib.pyplot as plt\n",
     "import numpy as np\n",
     "\n",
     "\n",
     "button = widgets.Button(description=\"Click Me!\")\n",
+    "output = widgets.Output()\n",
     "\n",
     "def on_button_clicked(b):\n",
-    "\tX = np.linspace(0, 2*np.pi)\n",
-    "\tY = np.sin(X)\n",
+    "\twith output:\n",
+    "\t\tX = np.linspace(0, 2*np.pi)\n",
+    "\t\tY = np.sin(X)\n",
     "\n",
-    "\t_, ax = plt.subplots()\n",
-    "\tax.plot(X, Y)\n",
+    "\t\tfig, ax = plt.subplots()\n",
+    "\t\tax.plot(X, Y)\n",
+    "\t\tplt.show(fig)\n",
     "\n",
-    "display(button)\n",
-    "button.on_click(on_button_clicked)\n"
+    "button.on_click(on_button_clicked)\n",
+    "\n",
+    "output"
    ]
   },
   {
@@ -32,7 +35,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "display(button)"
+    "button"
    ]
   }
  ],

src/test/datascience/widgets/notebooks/interactive_function.ipynb

@@ -7,11 +7,15 @@
    "outputs": [],
    "source": [
     "from ipywidgets import widgets, interact\n",
+    "output = widgets.Output()\n",
+    "display(output)\n",
+    "\n",
     "def do_something(filter_text):\n",
-    "    print(f\"Executing do_something with '{filter_text}'\")\n",
+    "    with output:\n",
+    "        print(f\"Executing do_something with '{filter_text}'\")\n",
     "    return filter_text\n",
-    "    \n",
-    "    \n",
+    "\n",
+    "\n",
     "interact(do_something, filter_text=widgets.Text(value='Foo'))\n",
     "do_something('Hello World')"
    ]

src/test/datascience/widgets/standardWidgets.vscode.common.test.ts

@@ -31,8 +31,7 @@ import {
     runCell,
     selectDefaultController,
     waitForCellExecutionToComplete,
-    waitForExecutionCompletedSuccessfully,
-    waitForTextOutput
+    waitForExecutionCompletedSuccessfully
 } from '../notebook/helper';
 import { initializeWidgetComms, Utils } from './commUtils';
 import { WidgetRenderingTimeoutForTests } from './constants';
@@ -237,24 +236,6 @@ suite('Standard IPyWidget Tests @widgets', function () {
             await assertOutputContainsHtml(cell1, comms, ['Button clicked']);
             await assertOutputContainsHtml(cell2, comms, ['Button clicked']);
         });
-        test('Button Widget with custom comm message', async () => {
-            await initializeNotebookForWidgetTest(
-                disposables,
-                {
-                    templateFile: 'button_widget_comm_msg.ipynb'
-                },
-                editor
-            );
-            const [cell0, cell1] = window.activeNotebookEditor!.notebook.getCells();
-
-            await executeCellAndWaitForOutput(cell0, comms);
-            await executeCellAndWaitForOutput(cell1, comms);
-            await assertOutputContainsHtml(cell0, comms, ['Click Me!', '<button']);
-
-            // Click the button and verify we have output in the same cell.
-            await clickWidget(comms, cell0, 'button');
-            await waitForTextOutput(cell0, 'Button clicked.', 1, false);
-        });
         test.skip('Widget renders after executing a notebook which was saved after previous execution', async () => {
             // // https://github.com/microsoft/vscode-jupyter/issues/8748
             // await initializeNotebookForWidgetTest(disposables, { templateFile: 'standard_widgets.ipynb' }, editor);
@@ -482,33 +463,6 @@ suite('Standard IPyWidget Tests @widgets', function () {
                 () => `Output doesn't contain text 'Bar' or still contains 'Outside, Inside, Foo', html is ${html}`
             );
         });
-        test('Interactive Button', async () => {
-            await initializeNotebookForWidgetTest(
-                disposables,
-                {
-                    templateFile: 'interactive_button.ipynb'
-                },
-                editor
-            );
-            const cell = window.activeNotebookEditor!.notebook.cellAt(0);
-
-            await executeCellAndWaitForOutput(cell, comms);
-            await assertOutputContainsHtml(cell, comms, ['Click Me!', '<button']);
-
-            // Click the button and verify we have output in other cells
-            await clickWidget(comms, cell, 'button');
-            await waitForCondition(
-                () => {
-                    assert.strictEqual(getTextOutputValue(cell.outputs[1]).trim(), 'Button clicked');
-                    return true;
-                },
-                5_000,
-                () =>
-                    `Expected 'Button clicked' to exist in ${
-                        cell.outputs.length > 1 ? getTextOutputValue(cell.outputs[1]) : '<Only one output>'
-                    }`
-            );
-        });
         test('Interactive Function', async () => {
             await initializeNotebookForWidgetTest(
                 disposables,

src/test/datascience/widgets/thirdpartyWidgets.vscode.common.test.ts

@@ -112,10 +112,10 @@ import { isWeb } from '../../../platform/common/utils/misc';
 
             await executeCellAndWaitForOutput(cell0, comms);
             await executeCellAndWaitForOutput(cell1, comms);
-            await assertOutputContainsHtml(cell0, comms, ['Click Me!', '<button']);
+            await assertOutputContainsHtml(cell1, comms, ['Click Me!', '<button']);
 
             // Click the button and verify we have output in the same cell.
-            await clickWidget(comms, cell0, 'button');
+            await clickWidget(comms, cell1, 'button');
             await assertOutputContainsHtml(cell0, comms, ['>Figure 1<', '<canvas', 'Download plot']);
         });
         test('Render AnyWidget (test js<-->kernel comms with binary data)', async function () {