tests: add testing for Python 3.15

Author: parthea

.github/workflows/unittest.yml

@@ -18,6 +18,7 @@ env:
   NOX_ENVDIR: "/tmp/shared_nox_envs"
   NOX_DEFAULT_VENV_BACKEND: "uv"
   UV_VENV_SEED: "1"
+  UV_PRERELEASE: "allow"
   # Note: PARALLEL_WORKERS must remain "1" for unit tests because running pytest concurrently
   # on the same runner VM can cause socket/IPC/process deadlocks across packages.
   PARALLEL_WORKERS: "1"
@@ -29,12 +30,13 @@ jobs:
       matrix: ${{ steps.set-matrix.outputs.matrix }}
       is_full_run: ${{ steps.check-label.outputs.is_full_run }}
     env:
-      MAX_SHARDS: 16
+      MAX_SHARDS: 20
       # Define weights for long-running unit tests to balance shard execution time
       # Each weight is roughly 1 minute of expected execution time
       # Default for unset packages is 1
       PACKAGE_WEIGHTS: |
         bigframes: 6
+        sqlalchemy-spanner: 6
         google-ai-generativelanguage: 4
         google-auth: 5
         google-cloud-compute: 12
@@ -81,9 +83,8 @@ jobs:
     if: needs.initialize.outputs.matrix != '[]' && needs.initialize.outputs.matrix != ''
     runs-on: ubuntu-22.04
     strategy:
-      fail-fast: true
       matrix:
-        python: ['3.10', "3.11", "3.12", "3.13", "3.14"]
+        python: ["3.10", "3.11", "3.12", "3.13", "3.14", "3.15"]
         package_shard: ${{ fromJson(needs.initialize.outputs.matrix) }}
     name: ${{ matrix.package_shard.is_sharded && format('unit ({0}, {1})', matrix.python, matrix.package_shard.name) || format('unit ({0})', matrix.python) }}
     steps:
@@ -100,10 +101,40 @@ jobs:
       with:
         python-version: ${{ matrix.python }}
         cache: 'pip'
-    - name: Install nox
+        allow-prereleases: true
+    - name: Setup uv
+      uses: astral-sh/setup-uv@d4b2f3b6ecc6e67c4457f6d3e41ec42d3d0fcb86 # v5
+      with:
+        enable-cache: true
+        cache-dependency-glob: 'packages/**/testing/constraints*.txt'
+    - name: Install nox and nox-uv
       run: |
-        python -m pip install --upgrade setuptools pip wheel
-        python -m pip install nox uv
+        uv pip install --system nox nox-uv
+    # Caches local wheels for Python 3.15+ to avoid repeatedly downloading or building heavy libraries.
+    # Follow https://github.com/grpc/grpc/issues/41010 for updates.
+    - name: Cache Built Python 3.15 Wheels
+      if: matrix.python == '3.15'
+      uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+      with:
+        path: .uv-wheel-cache
+        key: ${{ runner.os }}-uv-wheels-3.15-${{ hashFiles('packages/**/testing/constraints*.txt') }}
+        restore-keys: |
+          ${{ runner.os }}-uv-wheels-3.15-
+    # TODO: Remove this step once official Python 3.15 wheels for grpcio are published to PyPI.
+    # See https://github.com/grpc/grpc/issues/41010#issuecomment-4848264910 for details.
+    - name: Install grpcio wheel for Python 3.15
+      if: matrix.python == '3.15'
+      run: |
+        mkdir -p .uv-wheel-cache
+        WHEEL_FILE=".uv-wheel-cache/grpcio-1.83.0.dev0-cp315-cp315-manylinux2014_x86_64.manylinux_2_17_x86_64.whl"
+        if [ ! -f "$WHEEL_FILE" ]; then
+          curl -L "https://packages.grpc.io/archive/2026/06/5ccdab32010f762634e1082d19be53cf60458456-b37e49c7-5e62-4cbe-870a-c599bb907b04/python/grpcio/grpcio-1.83.0.dev0-cp315-cp315-manylinux2014_x86_64.manylinux_2_17_x86_64.whl" -o "$WHEEL_FILE"
+        fi
+        echo "d7706633cd5d97a8b8d3c6ed36c5940722a9b5cbb47f0d10bc433ee27af36ff0  $WHEEL_FILE" | sha256sum -c
+        uv pip install --system "$WHEEL_FILE"
+        echo "UV_FIND_LINKS=${{ github.workspace }}/.uv-wheel-cache" >> $GITHUB_ENV
+        echo "UV_CACHE_DIR=${{ github.workspace }}/.uv-wheel-cache" >> $GITHUB_ENV
+        echo "UV_PRERELEASE=allow" >> $GITHUB_ENV
     - name: Run unit tests for ${{ matrix.package_shard.description }}
       env:
         BUILD_TYPE: presubmit

ci/get_package_shards.py

@@ -165,7 +165,7 @@ def group_packages(packages_map):
 
     # Dynamically determine target weight to balance across max shards.
     max_shards = int(os.environ.get("MAX_SHARDS", 16))
-    target_weight = max(10, math.ceil(total_weight / max_shards))
+    target_weight = max(6, math.ceil(total_weight / max_shards))
 
     shards_list = []
     current_shard_items = []

ci/run_single_test.sh

@@ -90,6 +90,11 @@ case ${TEST_TYPE} in
             nox -s unit-3.14
             retval=$?
             ;;
+        "3.15")
+            # This is needed to speed up builds
+            nox --force-venv-backend uv -s unit-3.15
+            retval=$?
+            ;;
         *)
             echo "unsupported PY_VERSION"
             exit 1

packages/bigframes/bigframes/_magics.py

@@ -37,6 +37,9 @@
 )
 def _cell_magic(line, cell):
     ipython = get_ipython()
+    if ipython is None:
+        return
+
     args = magic_arguments.parse_argstring(_cell_magic, line)
     if not cell:
         print("Query is missing.")

packages/bigframes/noxfile.py

@@ -60,7 +60,7 @@
 
 DEFAULT_PYTHON_VERSION = "3.14"
 
-ALL_PYTHON = ["3.10", "3.11", "3.12", "3.13", "3.14"]
+ALL_PYTHON = ["3.10", "3.11", "3.12", "3.13", "3.14", "3.15"]
 UNIT_TEST_STANDARD_DEPENDENCIES = [
     "mock",
     PYTEST_VERSION,
@@ -283,6 +283,10 @@ def run_unit(session, install_test_extra):
 @nox.session(python=ALL_PYTHON)
 @nox.parametrize("test_extra", [True, False])
 def unit(session, test_extra):
+    if session.python == "3.15":
+        session.skip(
+            "Skipping 3.15 until wheels are available for pyarrow. Also pyproj wheels are needed for dependency geopandas."
+        )
     if test_extra:
         run_unit(session, install_test_extra=test_extra)
     else:

packages/bigquery-magics/noxfile.py

@@ -41,6 +41,7 @@
     "3.12",
     "3.13",
     "3.14",
+    "3.15",
 ]
 
 UNIT_TEST_STANDARD_DEPENDENCIES = [
@@ -237,6 +238,10 @@ def install_unittest_dependencies(session, *constraints):
 @nox.session(python=UNIT_TEST_PYTHON_VERSIONS)
 def unit(session):
     # Install all test dependencies, then install this package in-place.
+    if session.python == "3.15":
+        session.skip(
+            "Skipping 3.15 until wheels are available for pyproj needed for dependency geopandas"
+        )
 
     constraints_path = str(
         CURRENT_DIRECTORY / "testing" / f"constraints-{session.python}.txt"

packages/bigquery-magics/testing/constraints-3.15.txt

@@ -42,6 +42,7 @@
     "3.12",
     "3.13",
     "3.14",
+    "3.15",
 ]
 
 UNIT_TEST_STANDARD_DEPENDENCIES = [
@@ -302,6 +303,8 @@ def prerelease(session, tests_path):
 @nox.parametrize("test_type", ["unit", "compliance"])
 def unit(session, test_type):
     """Run the unit test suite."""
+    if session.python == "3.15":
+        session.skip("Skipping 3.15 until wheels are available for pyarrow.")
 
     # Compliance tests only run on the latest Python version
     if test_type == "compliance" and session.python != DEFAULT_PYTHON_VERSION:

packages/db-dtypes/noxfile.py

@@ -34,6 +34,7 @@
     "3.12",
     "3.13",
     "3.14",
+    "3.15",
 ]
 ALL_PYTHON = list(UNIT_TEST_PYTHON_VERSIONS)