Drop support for python 3.10, add 3.15.

.github/workflows/test.yml

@@ -57,42 +57,39 @@ jobs:
           #          if minor == int(dev_python_minor):
           #              # The range trick above doesn't work for threaded builds, so we'll
           #              # just be stuck with last prerelease until we update dev_python_minor.
-          #              configs.append((f"3.{minor}t-dev", f"py3{minor}"))
+          #              configs.append((f"3.{minor}t-dev", f"py3{minor}t"))
           #          else:
-          #              configs.append((f"3.{minor}t", f"py3{minor}"))
-          #    # Early versions of 3.10 and 3.11 had different deprecation
+          #              configs.append((f"3.{minor}t", f"py3{minor}t"))
+          #    # Early versions of 3.11 had different deprecation
           #    # warnings in asyncio. Test with them too to make sure everything
           #    # works the same way.
-          #    configs.append(("3.10.8", "py310-full"))
           #    configs.append(("3.11.0", "py311-full"))
           #    # Pypy is a lot slower due to jit warmup costs, so don't run the
           #    # "full" test config there.
-          #    configs.append(("pypy-3.10", "pypy3"))
+          #    configs.append(("pypy-3.11", "pypy3"))
           #    # Docs python version must be synced with tox.ini
           #    configs.append((f"3.{default_python_minor}", "docs"))
           #    for version, tox_env in configs:
           #      cog.outl(f"  - python: '{version}'")
           #      cog.outl(f"    tox_env: {tox_env}")
           #    ]]]
-          - python: '3.10'
-            tox_env: py310-full
           - python: '3.11'
             tox_env: py311-full
           - python: '3.12'
             tox_env: py312-full
           - python: '3.13'
             tox_env: py313-full
           - python: '3.14'
-            tox_env: py314
-          - python: '3.14t-dev'
+            tox_env: py314-full
+          - python: '3.14t'
             tox_env: py314t
-          - python: '3.15-dev'
+          - python: '3.15.0-dev - 3.15'
             tox_env: py315
-          - python: '3.10.8'
-            tox_env: py310-full
+          - python: '3.15t-dev'
+            tox_env: py315t
           - python: '3.11.0'
             tox_env: py311-full
-          - python: 'pypy-3.10'
+          - python: 'pypy-3.11'
             tox_env: pypy3
           - python: '3.13'
             tox_env: docs
@@ -175,3 +172,20 @@ jobs:
           # [[[cog cog.outl(f"CIBW_BUILD: cp3{default_python_minor}-manylinux*")]]]
           CIBW_BUILD: cp313-manylinux*
           # [[[end]]]
+
+  test_cog:
+    # Run cog and ensure that nothing changes, to make sure that cog-generated files are not
+    # edited manually.
+    name: Test cog generation
+    runs-on: ubuntu-24.04
+    needs: test_quick
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          persist-credentials: false
+      - uses: astral-sh/setup-uv@v7
+        name: Install uv
+      - name: Run cog
+        run: maint/scripts/runcog.sh
+      - name: Check for changes
+        run: git diff --exit-code

maint/scripts/runcog.sh

@@ -10,10 +10,10 @@
 # dev_python_minor is the version of Python that is currently under development
 # and is used to install pre-release versions of Python in CI.
 uvx --from cogapp cog \
-    -D min_python_minor=10 \
-    -D max_python_minor=14 \
+    -D min_python_minor=11 \
+    -D max_python_minor=15 \
     -D min_python_threaded_minor=14 \
-    -D max_python_threaded_minor=14 \
+    -D max_python_threaded_minor=15 \
     -D default_python_minor=13 \
-    -D dev_python_minor=14 \
+    -D dev_python_minor=15 \
     -r $(git grep -l '\[\[\[cog')

pyproject.toml

@@ -6,7 +6,7 @@ build-backend = "setuptools.build_meta"
 # [[[cog
 #    cog.outl(f"target-version = ['py3{min_python_minor}']")
 # ]]]
-target-version = ['py310']
+target-version = ['py311']
 #[[[end]]]
 
 [tool.cibuildwheel]
@@ -15,7 +15,7 @@ target-version = ['py310']
 #    versions += ["cp314t*"]
 #    cog.outl(f"build = \"{" ".join(versions)}\"")
 # ]]]
-build = "cp310* cp311* cp312* cp313* cp314* cp314t*"
+build = "cp311* cp312* cp313* cp314* cp315* cp314t*"
 #[[[end]]]
 test-command = "python -m tornado.test"
 

setup.cfg

@@ -3,7 +3,7 @@ license_file = LICENSE
 
 [mypy]
 # [[[cog cog.outl(f"python_version = 3.{min_python_minor}")]]]
-python_version = 3.10
+python_version = 3.11
 # [[[end]]]
 no_implicit_optional = True
 

setup.py

@@ -46,8 +46,8 @@
         #   cog.outl(")]")
         #   cog.outl(f"bdist_wheel_options = {{\"py_limited_api\": \"cp3{min_python_minor}\"}}")
         #   ]]]
-        define_macros = [("Py_LIMITED_API", "0x030a0000")]
-        bdist_wheel_options = {"py_limited_api": "cp310"}
+        define_macros = [("Py_LIMITED_API", "0x030b0000")]
+        bdist_wheel_options = {"py_limited_api": "cp311"}
         # [[[end]]]
     else:
         define_macros = []
@@ -77,7 +77,7 @@
     name="tornado",
     version=version,
     # [[[cog cog.outl(f"python_requires=\">= 3.{min_python_minor}\",")]]]
-    python_requires=">= 3.10",
+    python_requires=">= 3.11",
     # [[[end]]]
     packages=["tornado", "tornado.test", "tornado.platform"],
     package_data={
@@ -122,11 +122,11 @@
         #   for minor in range(int(min_python_minor), int(max_python_minor) + 1):
         #     cog.outl(f"\"Programming Language :: Python :: 3.{minor}\",")
         #   ]]]
-        "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
         "Programming Language :: Python :: 3.12",
         "Programming Language :: Python :: 3.13",
         "Programming Language :: Python :: 3.14",
+        "Programming Language :: Python :: 3.15",
         # [[[end]]]
         "Programming Language :: Python :: Implementation :: CPython",
         "Programming Language :: Python :: Implementation :: PyPy",

tornado/locale.py

@@ -350,10 +350,10 @@ def format_date(
            datetimes are still assumed to be UTC).
         """
         if isinstance(date, (int, float)):
-            date = datetime.datetime.fromtimestamp(date, datetime.timezone.utc)
+            date = datetime.datetime.fromtimestamp(date, datetime.UTC)
         if date.tzinfo is None:
-            date = date.replace(tzinfo=datetime.timezone.utc)
-        now = datetime.datetime.now(datetime.timezone.utc)
+            date = date.replace(tzinfo=datetime.UTC)
+        now = datetime.datetime.now(datetime.UTC)
         if date > now:
             if relative and (date - now).seconds < 60:
                 # Due to click skew, things are some things slightly

tornado/test/httpclient_test.py

@@ -988,7 +988,7 @@ def test_body_setter(self):
         self.assertEqual(request.body, utf8("foo"))
 
     def test_if_modified_since(self):
-        http_date = datetime.datetime.now(datetime.timezone.utc)
+        http_date = datetime.datetime.now(datetime.UTC)
         request = HTTPRequest("http://example.com", if_modified_since=http_date)
         self.assertEqual(
             request.headers, {"If-Modified-Since": format_timestamp(http_date)}

tornado/test/httputil_test.py

@@ -581,19 +581,17 @@ def test_time_tuple(self):
 
     def test_utc_naive_datetime(self):
         self.check(
-            datetime.datetime.fromtimestamp(
-                self.TIMESTAMP, datetime.timezone.utc
-            ).replace(tzinfo=None)
+            datetime.datetime.fromtimestamp(self.TIMESTAMP, datetime.UTC).replace(
+                tzinfo=None
+            )
         )
 
     def test_utc_naive_datetime_deprecated(self):
         with ignore_deprecation():
             self.check(datetime.datetime.utcfromtimestamp(self.TIMESTAMP))
 
     def test_utc_aware_datetime(self):
-        self.check(
-            datetime.datetime.fromtimestamp(self.TIMESTAMP, datetime.timezone.utc)
-        )
+        self.check(datetime.datetime.fromtimestamp(self.TIMESTAMP, datetime.UTC))
 
     def test_other_aware_datetime(self):
         # Other timezones are ignored; the timezone is always printed as GMT

tornado/test/locale_test.py

@@ -91,7 +91,7 @@ def test_format_date(self):
             locale.format_date(date, full_format=True), "April 28, 2013 at 6:35 pm"
         )
 
-        aware_dt = datetime.datetime.now(datetime.timezone.utc)
+        aware_dt = datetime.datetime.now(datetime.UTC)
         naive_dt = aware_dt.replace(tzinfo=None)
         for name, now in {"aware": aware_dt, "naive": naive_dt}.items():
             with self.subTest(dt=name):

tornado/test/process_test.py

@@ -147,8 +147,7 @@ def test_multi_process(self):
         result = subprocess.run(
             [sys.executable, "-c", _MULTI_PROCESS_TEST_SCRIPT],
             env=env,
-            stdout=subprocess.PIPE,
-            stderr=subprocess.PIPE,
+            capture_output=True,
             timeout=30,
         )
         if result.returncode != 0:

tornado/test/web_test.py

@@ -486,9 +486,7 @@ def test_set_cookie_expires_days(self):
         self.assertIsNotNone(match)
         assert match is not None  # for mypy
 
-        expires = datetime.datetime.now(datetime.timezone.utc) + datetime.timedelta(
-            days=10
-        )
+        expires = datetime.datetime.now(datetime.UTC) + datetime.timedelta(days=10)
         header_expires = email.utils.parsedate_to_datetime(match.groupdict()["expires"])
         self.assertLess(abs((expires - header_expires).total_seconds()), 10)
 
@@ -1892,7 +1890,7 @@ def test_date_header(self):
         response = self.fetch("/")
         header_date = email.utils.parsedate_to_datetime(response.headers["Date"])
         self.assertLess(
-            header_date - datetime.datetime.now(datetime.timezone.utc),
+            header_date - datetime.datetime.now(datetime.UTC),
             datetime.timedelta(seconds=2),
         )
 
@@ -3198,12 +3196,10 @@ def test_xsrf_httponly(self):
         match = re.match(".*; expires=(?P<expires>.+);.*", header)
         assert match is not None
 
-        expires = datetime.datetime.now(datetime.timezone.utc) + datetime.timedelta(
-            days=2
-        )
+        expires = datetime.datetime.now(datetime.UTC) + datetime.timedelta(days=2)
         header_expires = email.utils.parsedate_to_datetime(match.groupdict()["expires"])
         if header_expires.tzinfo is None:
-            header_expires = header_expires.replace(tzinfo=datetime.timezone.utc)
+            header_expires = header_expires.replace(tzinfo=datetime.UTC)
         self.assertTrue(abs((expires - header_expires).total_seconds()) < 10)
 
 

tornado/test/websocket_test.py

@@ -934,11 +934,9 @@ class PingCalculationTest(unittest.TestCase):
     def test_ping_sleep_time(self):
         from tornado.websocket import WebSocketProtocol13
 
-        now = datetime.datetime(2025, 1, 1, 12, 0, 0, tzinfo=datetime.timezone.utc)
+        now = datetime.datetime(2025, 1, 1, 12, 0, 0, tzinfo=datetime.UTC)
         interval = 10  # seconds
-        last_ping_time = datetime.datetime(
-            2025, 1, 1, 11, 59, 54, tzinfo=datetime.timezone.utc
-        )
+        last_ping_time = datetime.datetime(2025, 1, 1, 11, 59, 54, tzinfo=datetime.UTC)
         sleep_time = WebSocketProtocol13.ping_sleep_time(
             last_ping_time=last_ping_time.timestamp(),
             interval=interval,

tornado/web.py

@@ -715,7 +715,7 @@ def set_cookie(
         if domain:
             morsel["domain"] = domain
         if expires_days is not None and not expires:
-            expires = datetime.datetime.now(datetime.timezone.utc) + datetime.timedelta(
+            expires = datetime.datetime.now(datetime.UTC) + datetime.timedelta(
                 days=expires_days
             )
         if expires:
@@ -768,9 +768,7 @@ def clear_cookie(self, name: str, **kwargs: Any) -> None:
                 raise TypeError(
                     f"clear_cookie() got an unexpected keyword argument '{excluded_arg}'"
                 )
-        expires = datetime.datetime.now(datetime.timezone.utc) - datetime.timedelta(
-            days=365
-        )
+        expires = datetime.datetime.now(datetime.UTC) - datetime.timedelta(days=365)
         self.set_cookie(name, value="", expires=expires, **kwargs)
 
     def clear_all_cookies(self, **kwargs: Any) -> None:
@@ -2889,7 +2887,7 @@ def set_headers(self) -> None:
         if cache_time > 0:
             self.set_header(
                 "Expires",
-                datetime.datetime.now(datetime.timezone.utc)
+                datetime.datetime.now(datetime.UTC)
                 + datetime.timedelta(seconds=cache_time),
             )
             self.set_header("Cache-Control", "max-age=" + str(cache_time))
@@ -2914,7 +2912,7 @@ def should_return_304(self) -> bool:
             except Exception:
                 return False
             if if_since.tzinfo is None:
-                if_since = if_since.replace(tzinfo=datetime.timezone.utc)
+                if_since = if_since.replace(tzinfo=datetime.UTC)
             assert self.modified is not None
             if if_since >= self.modified:
                 return True
@@ -3096,7 +3094,7 @@ def get_modified_time(self) -> datetime.datetime | None:
         # that relies on this), we truncate the float here, although
         # I'm not sure that's the right thing to do.
         modified = datetime.datetime.fromtimestamp(
-            int(stat_result.st_mtime), datetime.timezone.utc
+            int(stat_result.st_mtime), datetime.UTC
         )
         return modified
 

tox.ini

@@ -18,7 +18,7 @@ envlist =
         #   versions += ["pypy3"]
         #   cog.outl(','.join(versions))
         #  ]]]
-        py310,py311,py312,py313,py314,pypy3
+        py311,py312,py313,py314,py315,pypy3
         # [[[end]]]
 
         # Build and test the docs with sphinx.
@@ -60,7 +60,7 @@ setenv =
        #    versions.insert(0, "py3")
        #    cog.outl(f"{{{",".join(versions)}}}: TORNADO_EXTENSION=1")
        # ]]]
-       {py3,py310,py311,py312,py313,py314}: TORNADO_EXTENSION=1
+       {py3,py311,py312,py313,py314,py315}: TORNADO_EXTENSION=1
        # [[[end]]]
        # CI workers are often overloaded and can cause our tests to exceed
        # the default timeout of 5s.