Merge remote-tracking branch 'upstream/main'

* upstream/main:
  Made cosmetic edits to docs/releases/6.0.txt.
  Refs #36664 -- Added Python 3.15 to daily builds.
  Refs #36499 -- Made TestUtilsHtml.test_strip_tags() assume behavior change in X.Y.0 version for Python 3.14+.
  Fixed #36677 -- Fixed scheduling of system checks in ParallelTestSuite workers.
  Made RemoteTestResultTest.test_pickle_errors_detection() compatible with tblib 3.2+.

Author: ArneTR

.github/workflows/schedule_tests.yml

@@ -23,6 +23,7 @@ jobs:
           - '3.12'
           - '3.13'
           - '3.14'
+          - '3.15-dev'
     name: Windows, SQLite, Python ${{ matrix.python-version }}
     continue-on-error: true
     steps:

django/test/runner.py

@@ -463,9 +463,6 @@ def _init_worker(
             process_setup(*process_setup_args)
         django.setup()
         setup_test_environment(debug=debug_mode)
-        call_command(
-            "check", stdout=io.StringIO(), stderr=io.StringIO(), databases=used_aliases
-        )
 
     db_aliases = used_aliases if used_aliases is not None else connections
     for alias in db_aliases:
@@ -477,6 +474,11 @@ def _init_worker(
                 connection._test_serialized_contents = value
         connection.creation.setup_worker_connection(_worker_id)
 
+    if is_spawn_or_forkserver:
+        call_command(
+            "check", stdout=io.StringIO(), stderr=io.StringIO(), databases=used_aliases
+        )
+
 
 def _run_subsuite(args):
     """

docs/releases/6.0.txt

@@ -124,7 +124,7 @@ Backends are configured via the :setting:`TASKS` setting. The :ref:`two
 built-in backends <task-available-backends>` included in this release are
 primarily intended for development and testing.
 
-Django handles task creation and queuing but does not provide a worker
+Django handles task creation and queuing, but does not provide a worker
 mechanism to run tasks. Execution must be managed by external infrastructure,
 such as a separate process or service.
 
@@ -575,7 +575,7 @@ to remove usage of these features.
 * Support for calling ``format_html()`` without passing args or kwargs is
   removed.
 
-* The default scheme for ``forms.URLField`` changed from ``"http"`` to
+* The default scheme for ``forms.URLField`` has changed from ``"http"`` to
   ``"https"``.
 
 * The ``FORMS_URLFIELD_ASSUME_HTTPS`` transitional setting is removed.

tests/requirements/py3.txt

@@ -6,8 +6,8 @@ black >= 25.9.0
 docutils >= 0.22
 geoip2 >= 4.8.0
 jinja2 >= 2.11.0
-numpy >= 1.26.0
-Pillow >= 10.1.0
+numpy >= 1.26.0; sys.platform != 'win32' or python_version < '3.15'
+Pillow >= 10.1.0; sys.platform != 'win32' or python_version < '3.15'
 # pylibmc/libmemcached can't be built on Windows.
 pylibmc; sys_platform != 'win32'
 pymemcache >= 3.4.0

tests/test_runner/test_parallel.py

@@ -32,6 +32,12 @@ class ExceptionThatFailsUnpickling(Exception):
     def __init__(self, arg):
         super().__init__()
 
+    def __reduce__(self):
+        # tblib 3.2+ makes exception subclasses picklable by default.
+        # Return (cls, ()) so the constructor fails on unpickle, preserving
+        # the needed behavior for test_pickle_errors_detection.
+        return (self.__class__, ())
+
 
 class ParallelTestRunnerTest(SimpleTestCase):
     """
@@ -170,6 +176,8 @@ def test_pickle_errors_detection(self):
         result = RemoteTestResult()
         result._confirm_picklable(picklable_error)
 
+        # The exception can be pickled but not unpickled.
+        pickle.dumps(not_unpicklable_error)
         msg = "__init__() missing 1 required positional argument"
         with self.assertRaisesMessage(TypeError, msg):
             result._confirm_picklable(not_unpicklable_error)

tests/utils_tests/test_html.py

@@ -116,21 +116,20 @@ def test_linebreaks(self):
                 self.check_output(linebreaks, lazystr(value), output)
 
     def test_strip_tags(self):
-        # Python fixed a quadratic-time issue in HTMLParser in 3.13.6, 3.12.12,
-        # 3.11.14, 3.10.19, and 3.9.24. The fix slightly changes HTMLParser's
-        # output, so tests for particularly malformed input must handle both
-        # old and new results. The check below is temporary until all supported
-        # Python versions and CI workers include the fix. See:
+        # Python fixed a quadratic-time issue in HTMLParser in 3.13.6, 3.12.12.
+        # The fix slightly changes HTMLParser's output, so tests for
+        # particularly malformed input must handle both old and new results.
+        # The check below is temporary until all supported Python versions and
+        # CI workers include the fix. See:
         # https://github.com/python/cpython/commit/6eb6c5db
         min_fixed = {
-            (3, 14): (3, 14),
             (3, 13): (3, 13, 6),
             (3, 12): (3, 12, 12),
-            (3, 11): (3, 11, 14),
-            (3, 10): (3, 10, 19),
-            (3, 9): (3, 9, 24),
         }
-        htmlparser_fixed = sys.version_info >= min_fixed[sys.version_info[:2]]
+        major_version = sys.version_info[:2]
+        htmlparser_fixed = sys.version_info >= min_fixed.get(
+            major_version, major_version
+        )
         items = (
             (
                 "<p>See: &#39;&eacute; is an apostrophe followed by e acute</p>",