Merge in the main branch

Author: encukou

.github/workflows/jit.yml

@@ -64,10 +64,10 @@ jobs:
         include:
           - target: i686-pc-windows-msvc/msvc
             architecture: Win32
-            runner: windows-2025-vs2026
+            runner: windows-2025
           - target: x86_64-pc-windows-msvc/msvc
             architecture: x64
-            runner: windows-2025-vs2026
+            runner: windows-2025
           - target: aarch64-pc-windows-msvc/msvc
             architecture: ARM64
             runner: windows-11-arm
@@ -183,6 +183,9 @@ jobs:
           - name: JIT without optimizations (Debug)
             configure_flags: --enable-experimental-jit --with-pydebug
             test_env: "PYTHON_UOPS_OPTIMIZE=0"
+          - name: JIT with stress testing (Debug)
+            configure_flags: --enable-experimental-jit --with-pydebug
+            test_env: "PYTHON_JIT_STRESS=1"
           - name: JIT with tail calling interpreter
             configure_flags: --enable-experimental-jit --with-tail-call-interp --with-pydebug
             use_clang: true

.github/workflows/reusable-san.yml

@@ -86,12 +86,12 @@ jobs:
       run: >-
         ./python -m test
         ${{ inputs.sanitizer == 'TSan' && '--tsan' || '' }}
-        -j4 -W
+        -j4 -W --timeout=900 --slowest
     - name: Parallel tests
       if: >-
         inputs.sanitizer == 'TSan'
         && fromJSON(inputs.free-threading)
-      run: ./python -m test --tsan-parallel --parallel-threads=4 -j4 -W
+      run: ./python -m test --tsan-parallel --parallel-threads=4 -j4 -W --timeout=600 --slowest
     - name: Display logs
       if: always()
       run: find "${GITHUB_WORKSPACE}" -name 'san_log.*' | xargs head -n 1000

.github/workflows/reusable-windows-msi.yml

@@ -17,7 +17,7 @@ env:
 jobs:
   build:
     name: installer for ${{ inputs.arch }}
-    runs-on: ${{ inputs.arch == 'arm64' && 'windows-11-arm' || 'windows-2025-vs2026' }}
+    runs-on: ${{ inputs.arch == 'arm64' && 'windows-11-arm' || 'windows-2025' }}
     timeout-minutes: 60
     env:
       ARCH: ${{ inputs.arch }}

.github/workflows/reusable-windows.yml

@@ -26,7 +26,7 @@ env:
 jobs:
   build:
     name: Build and test (${{ inputs.arch }}, ${{ inputs.interpreter }})
-    runs-on: ${{ inputs.arch == 'arm64' && 'windows-11-arm' || 'windows-2025-vs2026' }}
+    runs-on: ${{ inputs.arch == 'arm64' && 'windows-11-arm' || 'windows-2025' }}
     timeout-minutes: 60
     env:
       ARCH: ${{ inputs.arch }}

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: e05c5c0818279e5ac248ac9e954431ba58865e61  # frozen: v0.15.7
+    rev: 3b3f7c3f57fe9925356faf5fe6230835138be230  # frozen: v0.15.17
     hooks:
       - id: ruff-check
         name: Run Ruff (lint) on Platforms/Apple/
@@ -10,6 +10,11 @@ repos:
         name: Run Ruff (lint) on Doc/
         args: [--exit-non-zero-on-fix]
         files: ^Doc/
+      - id: ruff-check
+        name: Run Ruff (lint) on Lib/
+        args: [--exit-non-zero-on-fix]
+        files: ^Lib/
+        exclude: ^Lib/test/
       - id: ruff-check
         name: Run Ruff (lint) on Lib/test/
         args: [--exit-non-zero-on-fix]
@@ -18,6 +23,11 @@ repos:
         name: Run Ruff (lint) on Platforms/WASI/
         args: [--exit-non-zero-on-fix, --config=Platforms/WASI/.ruff.toml]
         files: ^Platforms/WASI/
+      - id: ruff-check
+        name: Run Ruff (lint) on Tools/
+        args: [--exit-non-zero-on-fix]
+        files: ^Tools/
+        exclude: ^Tools/(build|clinic|i18n|peg_generator|wasm)/
       - id: ruff-check
         name: Run Ruff (lint) on Tools/build/
         args: [--exit-non-zero-on-fix, --config=Tools/build/.ruff.toml]

.readthedocs.yml

@@ -11,19 +11,21 @@ build:
   os: ubuntu-24.04
   tools:
     python: "3"
+  apt_packages:
+    - jq
 
   jobs:
-    post_checkout:
+    post_system_dependencies:
       # https://docs.readthedocs.com/platform/stable/guides/build/skip-build.html#skip-builds-based-on-conditions
       #
-      # Cancel building pull requests when there aren't changes in the Doc
+      # Cancel building pull requests when there are no changes in the Doc
       # directory or RTD configuration, or if we can't cleanly merge the base
       # branch.
       - |
         set -eEux;
         if [ "$READTHEDOCS_VERSION_TYPE" = "external" ];
         then
-          base_branch=main;
+          base_branch=$(wget -qO- "https://api.github.com/repos/python/cpython/pulls/$READTHEDOCS_VERSION" | jq -er ".base.ref");
           git fetch --depth=50 origin $base_branch:origin-$base_branch;
           for attempt in $(seq 10);
           do

Doc/c-api/bytes.rst

@@ -384,14 +384,18 @@ Getters
 
    Get the writer size.
 
+   The function does not invalidate pointers returned by
+   :c:func:`PyBytesWriter_GetData`.
+
    The function cannot fail.
 
 .. c:function:: void* PyBytesWriter_GetData(PyBytesWriter *writer)
 
    Get the writer data: start of the internal buffer.
 
-   The pointer is valid until :c:func:`PyBytesWriter_Finish` or
-   :c:func:`PyBytesWriter_Discard` is called on *writer*.
+   The pointer remains valid until a :c:type:`PyBytesWriter` function other
+   than :c:func:`PyBytesWriter_GetData` or :c:func:`PyBytesWriter_GetSize` is
+   called on *writer*.
 
    The function cannot fail.
 

Doc/c-api/init_config.rst

@@ -623,6 +623,10 @@ Some options are read from the :mod:`sys` attributes. For example, the option
 
    .. versionadded:: 3.14
 
+   .. versionchanged:: next
+      The function now replaces :data:`sys.flags` (create a new object),
+      instead of modifying :data:`sys.flags` in-place.
+
 
 .. _pyconfig_api:
 

Doc/c-api/type.rst

@@ -563,10 +563,10 @@ but need extra remarks for use as slots:
    :c:member:`Slot ID <PySlot.sl_id>` for the name of the type,
    used to set :c:member:`PyTypeObject.tp_name`.
 
-   This slot (or :c:func:`PyType_Spec.name`) is required to create a type.
+   This slot (or :c:member:`PyType_Spec.name`) is required to create a type.
 
    This may not be used in :c:member:`PyType_Spec.slots`.
-   Use :c:func:`PyType_Spec.name` instead.
+   Use :c:member:`PyType_Spec.name` instead.
 
    .. impl-detail::
 
@@ -585,7 +585,7 @@ but need extra remarks for use as slots:
    The value must be positive.
 
    This may not be used in :c:member:`PyType_Spec.slots`.
-   Use :c:func:`PyType_Spec.basicsize` instead.
+   Use :c:member:`PyType_Spec.basicsize` instead.
 
    This slot may not be used with :c:func:`PyType_GetSlot`.
    Use :c:member:`PyTypeObject.tp_basicsize` instead if needed, but be aware
@@ -616,7 +616,7 @@ but need extra remarks for use as slots:
    :c:macro:`!Py_tp_extra_basicsize` is an error.
 
    This may not be used in :c:member:`PyType_Spec.slots`.
-   Use negative :c:func:`PyType_Spec.basicsize` instead.
+   Use negative :c:member:`PyType_Spec.basicsize` instead.
 
    This slot may not be used with :c:func:`PyType_GetSlot`.
 
@@ -648,7 +648,7 @@ but need extra remarks for use as slots:
    - With the :c:macro:`Py_TPFLAGS_ITEMS_AT_END` flag.
 
    This may not be used in :c:member:`PyType_Spec.slots`.
-   Use :c:func:`PyType_Spec.itemsize` instead.
+   Use :c:member:`PyType_Spec.itemsize` instead.
 
    This slot may not be used with :c:func:`PyType_GetSlot`.
 
@@ -663,13 +663,44 @@ but need extra remarks for use as slots:
    :c:func:`PyType_FromSpecWithBases` sets it automatically.
 
    This may not be used in :c:member:`PyType_Spec.slots`.
-   Use negative :c:func:`PyType_Spec.basicsize` instead.
+   Use negative :c:member:`PyType_Spec.basicsize` instead.
 
    This slot may not be used with :c:func:`PyType_GetSlot`.
    Use :c:func:`PyType_GetFlags` instead.
 
    .. versionadded:: 3.15
 
+.. c:macro:: Py_tp_bases
+
+   :c:member:`Slot ID <PySlot.sl_id>` for type flags, used to set
+   :c:member:`PyTypeObject.tp_bases`.
+
+   The slot can be set to a tuple of type objects which the newly created
+   type should inherit from, like the "positional arguments" of
+   a Python :ref:`class definition <class>`.
+
+   Alternately, the slot can be set to a single type object to specify
+   a single base.
+   The effect is the same as specifying a one-element tuple.
+
+   .. versionchanged:: 3.15
+
+      Previously, :c:macro:`!Py_tp_bases` required a tuple of types.
+
+.. c:macro:: Py_tp_base
+
+   Equivalent to :c:macro:`Py_tp_bases` (with ``s`` at the end).
+   If both are specified, :c:macro:`!Py_tp_bases` takes priority and
+   this slot is ignored.
+
+   .. versionchanged:: 3.15
+
+      Previously, :c:macro:`!Py_tp_base` required a single type, not a tuple.
+
+   .. soft-deprecated:: 3.15
+
+      When not targetting older Python versions, pefer :c:macro:`!Py_tp_bases`.
+
 The following slots do not correspond to public fields in the
 underlying structures:
 

Doc/c-api/typeobj.rst

@@ -1936,12 +1936,12 @@ and :c:data:`PyType_Type` effectively act as defaults.)
 
 .. c:member:: PyTypeObject* PyTypeObject.tp_base
 
-   .. corresponding-type-slot:: Py_tp_base
-
    An optional pointer to a base type from which type properties are inherited.  At
    this level, only single inheritance is supported; multiple inheritance require
    dynamically creating a type object by calling the metatype.
 
+   For the corresponding slot ID, see :c:macro:`Py_tp_base`.
+
    .. note::
 
        .. from Modules/xxmodule.c
@@ -2253,17 +2253,12 @@ and :c:data:`PyType_Type` effectively act as defaults.)
 
 .. c:member:: PyObject* PyTypeObject.tp_bases
 
-   .. corresponding-type-slot:: Py_tp_bases
-
    Tuple of base types.
 
    This field should be set to ``NULL`` and treated as read-only.
    Python will fill it in when the type is :c:func:`initialized <PyType_Ready>`.
 
-   For dynamically created classes, the :c:data:`Py_tp_bases`
-   :c:type:`slot <PyType_Slot>` can be used instead of the *bases* argument
-   of :c:func:`PyType_FromSpecWithBases`.
-   The argument form is preferred.
+   For the corresponding slot ID, see :c:macro:`Py_tp_bases`.
 
    .. warning::