feat: add support for python 3.12 (#400)

* feat: add support for python 3.12

* update exclude

* update noxfile

* add contraints file

* Disable warnings as errors

* use datetime.datetime.fromtimestamp instead of datetime.datetime.utcfromtimestamp(0) which is deprecated

* use datetime.timezone.utc

* add comment

.github/workflows/tests.yml

@@ -42,11 +42,13 @@ jobs:
     runs-on: ubuntu-20.04
     strategy:
       matrix:
-        python: ['3.6', '3.7', '3.8', '3.9', '3.10', '3.11']
+        python: ['3.6', '3.7', '3.8', '3.9', '3.10', '3.11', '3.12']
         variant: ['', 'cpp', 'upb']
         exclude:
           - variant: "cpp"
             python: 3.11
+          - variant: "cpp"
+            python: 3.12
     steps:
       - uses: actions/checkout@v4
       - name: Set up Python ${{ matrix.python }}

noxfile.py

@@ -29,6 +29,7 @@
     "3.9",
     "3.10",
     "3.11",
+    "3.12",
 ]
 
 # Error if a python version is missing
@@ -48,9 +49,14 @@ def unit(session, proto="python"):
     session.install("-e", ".[testing]", "-c", constraints_path)
     if proto == "cpp":  # 4.20 does not have cpp.
         session.install("protobuf==3.19.0")
+
+    # The warnings as errors flag `-W=error` was removed in
+    # https://github.com/googleapis/proto-plus-python/pull/400.
+    # It should be re-added once issue
+    # https://github.com/googleapis/proto-plus-python/issues/403 is fixed.
+    # See also https://github.com/protocolbuffers/protobuf/issues/12186.
     session.run(
         "py.test",
-        "-W=error",
         "--quiet",
         *(
             session.posargs  # Coverage info when running individual tests is annoying.

proto/datetime_helpers.py

@@ -21,7 +21,8 @@
 from google.protobuf import timestamp_pb2
 
 
-_UTC_EPOCH = datetime.datetime.utcfromtimestamp(0).replace(tzinfo=datetime.timezone.utc)
+_UTC_EPOCH = datetime.datetime.fromtimestamp(0, datetime.timezone.utc)
+
 _RFC3339_MICROS = "%Y-%m-%dT%H:%M:%S.%fZ"
 _RFC3339_NO_FRACTION = "%Y-%m-%dT%H:%M:%S"
 # datetime.strptime cannot handle nanosecond precision:  parse w/ regex

setup.py

@@ -56,6 +56,7 @@
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
+        "Programming Language :: Python :: 3.12",
         "Topic :: Software Development :: Code Generators",
         "Topic :: Software Development :: Libraries :: Python Modules",
     ],