test: adds pytest-xdist to nox sessions for experimentation

noxfile.py

@@ -18,11 +18,12 @@
 
 from __future__ import absolute_import
 
+from functools import wraps
 import os
 import pathlib
 import re
-import re
 import shutil
+import time
 from typing import Dict, List
 import warnings
 
@@ -48,6 +49,7 @@
     "asyncmock",
     "pytest",
     "pytest-cov",
+    "pytest-xdist",
     "pytest-asyncio",
 ]
 UNIT_TEST_EXTERNAL_DEPENDENCIES: List[str] = []
@@ -79,6 +81,7 @@
     "mock",
     "pytest",
     "google-cloud-testutils",
+    "pytest-xdist",
 ]
 SYSTEM_TEST_EXTERNAL_DEPENDENCIES: List[str] = []
 SYSTEM_TEST_LOCAL_DEPENDENCIES: List[str] = []
@@ -106,6 +109,26 @@
 
 CURRENT_DIRECTORY = pathlib.Path(__file__).parent.absolute()
 
+def _calculate_duration(func):
+    """This decorator prints the execution time for the decorated function."""
+
+    @wraps(func)
+    def wrapper(*args, **kwargs):
+        start = time.monotonic()
+        result = func(*args, **kwargs)
+        end = time.monotonic()
+        total_seconds = round(end - start)
+        hours = total_seconds // 3600  # Integer division to get hours
+        remaining_seconds = total_seconds % 3600  # Modulo to find remaining seconds
+        minutes = remaining_seconds // 60
+        seconds = remaining_seconds % 60
+        human_time = f"{hours:}:{minutes:0>2}:{seconds:0>2}"
+        print(f"Session ran in {total_seconds} seconds ({human_time})")
+        return result
+
+    return wrapper
+
+
 nox.options.sessions = [
     "unit",
     "system",
@@ -124,6 +147,7 @@
 
 
 @nox.session(python=DEFAULT_PYTHON_VERSION)
+@_calculate_duration
 def lint(session):
     """Run linters.
 
@@ -140,6 +164,7 @@ def lint(session):
 
 
 @nox.session(python=DEFAULT_PYTHON_VERSION)
+@_calculate_duration
 def blacken(session):
     """Run black. Format code to uniform standard."""
     session.install(BLACK_VERSION)
@@ -150,6 +175,7 @@ def blacken(session):
 
 
 @nox.session(python=DEFAULT_PYTHON_VERSION)
+@_calculate_duration
 def format(session):
     """
     Run isort to sort imports. Then run black
@@ -170,6 +196,7 @@ def format(session):
 
 
 @nox.session(python=DEFAULT_PYTHON_VERSION)
+@_calculate_duration
 def lint_setup_py(session):
     """Verify that setup.py is valid (including RST check)."""
     session.install("docutils", "pygments")
@@ -205,6 +232,7 @@ def install_unittest_dependencies(session, *constraints):
 
 
 @nox.session(python=UNIT_TEST_PYTHON_VERSIONS)
+@_calculate_duration
 @nox.parametrize(
     "protobuf_implementation",
     ["python", "upb", "cpp"],
@@ -237,6 +265,7 @@ def unit(session, protobuf_implementation, install_extras=True):
     # Run py.test against the unit tests.
     session.run(
         "py.test",
+        "-n=auto",
         "--quiet",
         f"--junitxml=unit_{session.python}_sponge_log.xml",
         "--cov=sqlalchemy_bigquery",
@@ -284,6 +313,7 @@ def install_systemtest_dependencies(session, *constraints):
 
 
 @nox.session(python=SYSTEM_TEST_PYTHON_VERSIONS)
+@_calculate_duration
 def system(session):
     """Run the system test suite."""
     constraints_path = str(
@@ -311,6 +341,7 @@ def system(session):
     if system_test_exists:
         session.run(
             "py.test",
+            "-n=auto",
             "--quiet",
             f"--junitxml=system_{session.python}_sponge_log.xml",
             system_test_path,
@@ -319,6 +350,7 @@ def system(session):
     if system_test_folder_exists:
         session.run(
             "py.test",
+            "-n=auto",
             "--quiet",
             f"--junitxml=system_{session.python}_sponge_log.xml",
             system_test_folder_path,
@@ -327,6 +359,7 @@ def system(session):
 
 
 @nox.session(python=SYSTEM_TEST_PYTHON_VERSIONS)
+@_calculate_duration
 def system_noextras(session):
     """Run the system test suite."""
     constraints_path = str(
@@ -356,6 +389,7 @@ def system_noextras(session):
     if system_test_exists:
         session.run(
             "py.test",
+            "-n=auto",
             "--quiet",
             f"--junitxml=system_{session.python}_sponge_log.xml",
             system_test_path,
@@ -364,6 +398,7 @@ def system_noextras(session):
     if system_test_folder_exists:
         session.run(
             "py.test",
+            "-n=auto",
             "--quiet",
             f"--junitxml=system_{session.python}_sponge_log.xml",
             system_test_folder_path,
@@ -372,6 +407,7 @@ def system_noextras(session):
 
 
 @nox.session(python=SYSTEM_TEST_PYTHON_VERSIONS[-1])
+@_calculate_duration
 def compliance(session):
     """Run the SQLAlchemy dialect-compliance system tests"""
     constraints_path = str(
@@ -389,6 +425,7 @@ def compliance(session):
     session.install(
         "mock",
         "pytest",
+        "pytest-xdist",
         "pytest-rerunfailures",
         "google-cloud-testutils",
         "-c",
@@ -406,10 +443,11 @@ def compliance(session):
 
     session.run(
         "py.test",
+        "-n=2",
         "-vv",
         f"--junitxml=compliance_{session.python}_sponge_log.xml",
-        "--reruns=3",
-        "--reruns-delay=60",
+        "--reruns=0",
+        "--reruns-delay=1",
         "--only-rerun=Exceeded rate limits",
         "--only-rerun=Already Exists",
         "--only-rerun=Not found",
@@ -426,6 +464,7 @@ def compliance(session):
 
 
 @nox.session(python=DEFAULT_PYTHON_VERSION)
+@_calculate_duration
 def cover(session):
     """Run the final coverage report.
 
@@ -439,6 +478,7 @@ def cover(session):
 
 
 @nox.session(python="3.10")
+@_calculate_duration
 def docs(session):
     """Build the docs for this library."""
 
@@ -476,6 +516,7 @@ def docs(session):
 
 
 @nox.session(python="3.10")
+@_calculate_duration
 def docfx(session):
     """Build the docfx yaml files for this library."""
 
@@ -524,6 +565,7 @@ def docfx(session):
 
 
 @nox.session(python="3.12")
+@_calculate_duration
 @nox.parametrize(
     "protobuf_implementation",
     ["python", "upb", "cpp"],
@@ -612,6 +654,7 @@ def prerelease_deps(session, protobuf_implementation):
     if os.path.exists(system_test_path):
         session.run(
             "py.test",
+            "-n=auto",
             "--verbose",
             f"--junitxml=system_{session.python}_sponge_log.xml",
             system_test_path,
@@ -623,6 +666,7 @@ def prerelease_deps(session, protobuf_implementation):
     if os.path.exists(system_test_folder_path):
         session.run(
             "py.test",
+            "-n=auto",
             "--verbose",
             f"--junitxml=system_{session.python}_sponge_log.xml",
             system_test_folder_path,

sqlalchemy_bigquery/base.py

@@ -69,6 +69,25 @@
 
 TABLE_VALUED_ALIAS_ALIASES = "bigquery_table_valued_alias_aliases"
 
+from sqlalchemy.testing.provision import create_db, drop_db
+@create_db.for_db("bigquery")
+def _bigquery_create_db(cfg, eng, ident):
+    # This and _bigquery_drop_db are adequate to get past the errors generated when using xdist:
+    # NotImplementedError: no DB creation routine for cfg
+    # NotImplementedError: no DB drop routine for cfg
+    #
+    # HOWEVER... we need to populate this in some way to create dbs that
+    # work. THere are examples of create_db style functions in various 
+    # dialects provision.py files.
+    # This sqlalchemy issue speaks to this problem:
+    # https://github.com/sqlalchemy/sqlalchemy/discussions/10948 
+    pass 
+
+@drop_db.for_db("bigquery")
+def _bigquery_drop_db(cfg, eng, ident):
+    pass # _drop_dbs_w_ident(eng.url.database, eng.driver, ident)
+    # SEE note above for create_db
+
 
 def assert_(cond, message="Assertion failed"):  # pragma: NO COVER
     if not cond: