chore: updates to noxfile sessions and python versions

Author: chalmerlowe

packages/google-cloud-storage/noxfile.py

@@ -15,25 +15,32 @@
 # limitations under the License.
 
 from __future__ import absolute_import
+
 import os
 import pathlib
 import shutil
 
 import nox
 
-
 BLACK_VERSION = "black==23.7.0"
+ISORT_VERSION = "isort==5.12.0"
 BLACK_PATHS = ["docs", "google", "tests", "noxfile.py", "setup.py"]
 
 DEFAULT_PYTHON_VERSION = "3.14"
-SYSTEM_TEST_PYTHON_VERSIONS = ["3.10", "3.14"]
 UNIT_TEST_PYTHON_VERSIONS = [
+    "3.8",
+    "3.9",
     "3.10",
     "3.11",
     "3.12",
     "3.13",
     "3.14",
 ]
+
+ALL_PYTHON = list(UNIT_TEST_PYTHON_VERSIONS)
+ALL_PYTHON.extend(["3.7"])
+SYSTEM_TEST_PYTHON_VERSIONS = ["3.12"]
+
 CONFORMANCE_TEST_PYTHON_VERSIONS = ["3.12"]
 
 CURRENT_DIRECTORY = pathlib.Path(__file__).parent.absolute()
@@ -43,19 +50,18 @@
 
 nox.options.sessions = [
     "blacken",
-    "conftest_retry",
-    "docfx",
-    "docs",
+    "format",
     "lint",
     "lint_setup_py",
+    "mypy",
+    "conftest_retry",
     "system",
-    "unit-3.10",
-    "unit-3.11",
-    "unit-3.12",
-    "unit-3.13",
-    "unit-3.14",
-    # cover must be last to avoid error `No data to report`
+    "unit",    # cover must be last to avoid error `No data to report`
     "cover",
+    "docfx",
+    "docs",
+    "core_deps_from_source",
+    "prerelease_deps",
 ]
 
 
@@ -77,7 +83,7 @@ def lint(session):
     session.run("flake8", "google", "tests")
 
 
-@nox.session(python="3.14")
+@nox.session(python=DEFAULT_PYTHON_VERSION)
 def blacken(session):
     """Run black.
 
@@ -146,7 +152,7 @@ def default(session, install_extras=True):
     )
 
 
-@nox.session(python=UNIT_TEST_PYTHON_VERSIONS)
+@nox.session(python=ALL_PYTHON)
 def unit(session):
     """Run the unit test suite."""
     if session.python in ("3.7",):
@@ -364,6 +370,12 @@ def docfx(session):
 def prerelease_deps(session, protobuf_implementation):
     """Run all tests with prerelease versions of dependencies installed."""
 
+    # Environment check: Only run tests if the environment variable is set.
+    if not os.environ.get("GOOGLE_APPLICATION_CREDENTIALS", ""):
+        session.skip(
+            "Credentials must be set via environment variable GOOGLE_APPLICATION_CREDENTIALS"
+        )
+
     # Install all test dependencies
     session.install("mock", "pytest", "pytest-cov", "brotli")
 
@@ -432,3 +444,36 @@ def prerelease_deps(session, protobuf_implementation):
             "PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION": protobuf_implementation,
         },
     )
+
+
+@nox.session(python=DEFAULT_PYTHON_VERSION)
+def mypy(session):
+    """Run the type checker."""
+    # TODO(https://github.com/googleapis/google-cloud-python/issues/16014):
+    # Add mypy tests
+    session.skip("mypy tests are not yet supported")
+
+
+@nox.session(python=DEFAULT_PYTHON_VERSION)
+def core_deps_from_source(session):
+    """Run all tests with core dependencies installed from source
+    rather than pulling the dependencies from PyPI.
+    """
+    # TODO(https://github.com/googleapis/google-cloud-python/issues/16014):
+    # Add core deps from source tests
+    session.skip("Core deps from source tests are not yet supported")
+
+
+@nox.session
+def format(session: nox.sessions.Session) -> None:
+    """
+    Run isort to sort imports. Then run black
+    to format code to uniform standard.
+    """
+    session.install(BLACK_VERSION, ISORT_VERSION)
+    python_files = [path for path in os.listdir(".") if path.endswith(".py")]
+
+    # Use the --fss option to sort imports using strict alphabetical order.
+    # See https://pycqa.github.io/isort/docs/configuration/options.html#force-sort-within-sections
+    session.run("isort", "--fss", *python_files)
+    session.run("black", *python_files)