fix: resolve double printing issue in anywidget mode

Author: shuoweil

bigframes/dataframe.py

@@ -792,13 +792,10 @@ def __repr__(self) -> str:
         if opts.repr_mode == "anywidget":
             # Try to display with anywidget, fall back to deferred if not in IPython
             try:
-                from IPython.display import display as ipython_display
-
                 from bigframes import display
 
                 widget = display.TableWidget(self.copy())
-                ipython_display(widget)
-                return ""  # Return empty string since we used display()
+                return widget._repr_html_()  # Return widget's HTML representation
             except (AttributeError, ValueError, ImportError):
                 # Not in IPython environment, fall back to deferred mode
                 return formatter.repr_query_job(self._compute_dry_run())

notebooks/dataframes/anywidget_mode.ipynb

@@ -73,11 +73,25 @@
    "id": "f289d250",
    "metadata": {},
    "outputs": [
+    {
+     "data": {
+      "application/vnd.jupyter.widget-view+json": {
+       "model_id": "071c0a905297406ba6c990cbbb8fc28d",
+       "version_major": 2,
+       "version_minor": 0
+      },
+      "text/plain": [
+       "TableWidget(page_size=10, row_count=5552452, table_html='<table border=\"1\" class=\"dataframe table table-stripe…"
+      ]
+     },
+     "metadata": {},
+     "output_type": "display_data"
+    },
     {
      "name": "stdout",
      "output_type": "stream",
      "text": [
-      "Computation deferred. Computation will process 171.4 MB\n"
+      "\n"
      ]
     }
    ],
@@ -130,9 +144,9 @@
     {
      "data": {
       "application/vnd.jupyter.widget-view+json": {
-       "model_id": "9e3e413eb0774a62818c58d217af8488",
+       "model_id": "042a3d55c51b4a3192cf1a942c6797e8",
        "version_major": 2,
-       "version_minor": 1
+       "version_minor": 0
       },
       "text/plain": [
        "TableWidget(page_size=10, row_count=5552452, table_html='<table border=\"1\" class=\"dataframe table table-stripe…"
@@ -143,11 +157,23 @@
     },
     {
      "data": {
-      "text/html": [],
+      "application/vnd.jupyter.widget-view+json": {
+       "model_id": "06e46087ecbe4e6d8bdc2ed7c9284a7d",
+       "version_major": 2,
+       "version_minor": 0
+      },
       "text/plain": [
-       "Computation deferred. Computation will process 171.4 MB"
+       "TableWidget(page_size=10, row_count=5552452, table_html='<table border=\"1\" class=\"dataframe table table-stripe…"
       ]
      },
+     "metadata": {},
+     "output_type": "display_data"
+    },
+    {
+     "data": {
+      "text/html": [],
+      "text/plain": []
+     },
      "execution_count": 6,
      "metadata": {},
      "output_type": "execute_result"
@@ -181,17 +207,16 @@
     {
      "data": {
       "application/vnd.jupyter.widget-view+json": {
-       "model_id": "df5e93f0d03f45cda67aa6da7f9ef1ae",
+       "model_id": "4da2aaa13f074229b022c7256ba7510b",
        "version_major": 2,
-       "version_minor": 1
+       "version_minor": 0
       },
       "text/plain": [
        "TableWidget(page_size=10, row_count=5552452, table_html='<table border=\"1\" class=\"dataframe table table-stripe…"
       ]
      },
-     "execution_count": 7,
      "metadata": {},
-     "output_type": "execute_result"
+     "output_type": "display_data"
     }
    ],
    "source": [
@@ -267,17 +292,16 @@
     {
      "data": {
       "application/vnd.jupyter.widget-view+json": {
-       "model_id": "a4ec5248708442fabc59c446c78a1304",
+       "model_id": "d2739b180f7d40b1b52ebab121ab7a8a",
        "version_major": 2,
-       "version_minor": 1
+       "version_minor": 0
       },
       "text/plain": [
        "TableWidget(page_size=10, row_count=5, table_html='<table border=\"1\" class=\"dataframe table table-striped tabl…"
       ]
      },
-     "execution_count": 9,
      "metadata": {},
-     "output_type": "execute_result"
+     "output_type": "display_data"
     }
    ],
    "source": [
@@ -287,14 +311,6 @@
     "print(f\"Small dataset pages: {math.ceil(small_widget.row_count / small_widget.page_size)}\")\n",
     "small_widget"
    ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "c4e5836b-c872-4a9c-b9ec-14f6f338176d",
-   "metadata": {},
-   "outputs": [],
-   "source": []
   }
  ],
  "metadata": {

tests/system/small/test_anywidget.py

@@ -12,13 +12,15 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from __future__ import annotations
+
+from unittest import mock
+
 import pandas as pd
 import pytest
 
 import bigframes as bf
 
-pytest.importorskip("anywidget")
-
 # Test constants to avoid change detector tests
 EXPECTED_ROW_COUNT = 6
 EXPECTED_PAGE_SIZE = 2
@@ -418,25 +420,15 @@ def test_setting_page_size_above_max_should_be_clamped(table_widget):
     # The page size is clamped to the maximum.
     assert table_widget.page_size == expected_clamped_size
 
-
-def test_widget_creation_should_load_css_for_rendering(table_widget):
     """
-    Given a TableWidget is created, when its resources are accessed,
-    it should contain the CSS content required for styling.
+    Test that the widget's CSS is loaded correctly.
     """
-    # The table_widget fixture creates the widget.
-    # No additional setup is needed.
-
-    # Access the CSS content.
     css_content = table_widget._css
-
-    # The content is a non-empty string containing a known selector.
-    assert isinstance(css_content, str)
-    assert len(css_content) > 0
     assert ".bigframes-widget .footer" in css_content
 
 
-def test_sql_anywidget_mode(session: bf.Session):
+@mock.patch("bigframes.display.TableWidget")
+def test_sql_anywidget_mode(mock_table_widget, session: bf.Session):
     """
     Test that a SQL query runs in anywidget mode.
     """
@@ -446,9 +438,8 @@ def test_sql_anywidget_mode(session: bf.Session):
         df = session.read_gbq(sql)
         # In a real environment, this would display a widget.
         # For testing, we just want to make sure we're in the anywidget code path.
-        # The `_repr_html_` method in anywidget mode will return an empty string
-        # and display the widget via IPython's display mechanism.
-        assert df._repr_html_() == ""
+        df._repr_html_()
+        mock_table_widget.assert_called_once()
 
 
 # TODO(shuowei): Add tests for custom index and multiindex