* feature: support compilers that use std::experimental::filesystem such as gcc7

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* only use this feature if cpp17

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* more specific namespace alias + style

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* move to pybind11 namespace

* no namespace alias

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* chore: bump changelog for 2.9.2

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* Update docs/changelog.rst

* style: bump black

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* fix: pycln broken by typer breakage

* Improve str exceptions

* Revert macro change just in case

* Make clang-tidy happy

* Fix one more clang-tidy issue

* Refactor duplicate method

* Revert "ci: test pypy 3.9 (#3789)"

This reverts commit 461937d3.

* Update ci.yml

* ci: test pypy 3.9

* ci: try a use of FindPython with PyPy

* Make capsule errors better match python

* Add missing move in sp matrix caster and microopt char concat

* Remove useless move

* Add a couple more std::move

* Missed one char

* Improve error_string

* Ensure no temp reallocs in errorString concat

* Remove useless move

* Add type_caster<std::monostate> for std::variant

Add type_caster<std::monostate>, allowing std::variant<std::monostate, ...>

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* Update test fn name

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Nearly every call site of cast_op<T> uses an r-value reference.

Except stl.h variant_caster::load_alternative for handling std::variant.

Fix that.

The docs were not 100% the same as we advertise with our
tooling function: most users do not want to strip symbols
in Debug builds.

updates:
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- [github.com/sirosen/texthooks: 0.2.2 → 0.3.1](https://github.com/sirosen/texthooks/compare/0.2.2...0.3.1)
- [github.com/hadialqattan/pycln: v1.2.4 → v1.2.5](https://github.com/hadialqattan/pycln/compare/v1.2.4...v1.2.5)
- [github.com/pre-commit/mirrors-mypy: v0.931 → v0.940](https://github.com/pre-commit/mirrors-mypy/compare/v0.931...v0.940)
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* PYBIND11_OBJECT_CVT should use namespace for error_already_set()

This change makes the macro usable outside of pybind11 namespace.

* added test for use of PYBIND11_OBJECT_CVT for classes in external to pybind11 namespaces

* Extended test_pytypes.cpp and test_pytest.py

The added test defines a dummy function that takes a custom-defined class external::float_
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* fixed memory leak in default constructor

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* Test out Python 3.11 migration

* Clean up a bit

* Remove todo

* Test workaround

* Fix potential bug uncovered in 3.11

* Try to fix it more

* last ditch fix

* Revert. Tp-traverse isn't the problem

* Test workaround

* Try this hack

* Revert MRO changes

* Use f_back properly

* Qualify auto

* Update include/pybind11/pybind11.h

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* Simplify code slightly

* Ensure co_varnames decref if dict_getitem throws

* Eager decref f_code

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* Use sysconfig in Python >= 3.10

Rely on sysconfig for installation paths for Python >= 3.10. distutils
has been deprecated and will be removed.

Fixes: #3677

* Explicitly select the posix_prefix scheme for platinclude on Debian

Debian's default scheme is posix_local, for installing locally-built
packages to /usr/local/.  We want to find the Python headers in /usr/,
so search posix_prefix.

* chore: minor fixes for newer PyPys

* ci: fix issue with PyPy

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* cast: Qualify symbol usage in PYBIND11_TYPE_CASTER

Permits using macro outside of pybind11::detail

* fixup! review

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* Fix merge comments

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* Assert early if AsString fails

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* [pre-commit.ci] pre-commit autoupdate

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- [github.com/pre-commit/mirrors-clang-format: v13.0.0 → v13.0.1](https://github.com/pre-commit/mirrors-clang-format/compare/v13.0.0...v13.0.1

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* Update .pre-commit-config.yaml

* ci: specify which windows image to use

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* Clear local internals after finalizing interpreter

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* Clear Python error state if pybind11::weakref() fails.

The weakref() constructor calls pybind11_fail() without clearing any
Python interpreter error state. If a client catches the C++ exception
thrown by pybind11_fail(), the Python interpreter will be left in an
error state.

* Add test case for failing to create weakref

* Add Debug asserts for pybind11 fail

* Make error handling more pythonic

* Does this fix PyPy?

* Adapt test to PyPy differences

* Simplify test to remove redundancy

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* Removing C++20 condition for MSVC is_template_base_of decltype workaround.

* `-DDOWNLOAD_EIGEN=ON` for MSVC 2022 C++20

* `-DDOWNLOAD_EIGEN=ON` for MSVC 2019 C++20

* `-DPYBIND11_WERROR=OFF` for MSVC C++20 (2019, 2020)

* Restoring `defined(PYBIND11_CPP20)` in common.h

* pragma warning(disable : 5054) in eigen.h

* Reverting `-DPYBIND11_WERROR=OFF` changes.

* fix: add pylint and fix issue

* chore: add pylint to pre-commit

* fix: local variable warning surfaced mistake in intree

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* Changing `_MSC_VER` guard to `< 1910` (dropping MSVC 2015).

* Removing MSVC 2015 from ci.yml, and .appveyor.yml entirely.

* Bringing back .appveyor.yml from master.

* appveyor Visual Studio 2017

* 1st manual pass, builds & tests with unix_clang, before pre-commit.

* After clang-format (via pre-commit).

* Manual pass looking for "2015", builds & tests with unix_clang, before pre-commit.

* Backtracking for include/pybind11 changes in previous commit.

git checkout d07865846c7d31dd61111e6df801864327b65070 include/pybind11/attr.h include/pybind11/detail/common.h include/pybind11/functional.h

--------------------

CI #4160 errors observed:

https://github.com/pybind/pybind11/pull/3722/commits/2a26873727214c5f1e159cba98f5c625b908381a
https://github.com/pybind/pybind11/runs/5168332130?check_suite_focus=true

$ grep ' error C' *.txt | sed 's/2022-02-12[^ ]*//' | sed 's/^[0-9][0-9]*//' | sed 's/^.*\.txt: //' | sort | uniqD:\a\pybind11\pybind11\include\pybind11\cast.h(1364,1): error C2752: 'pybind11::detail::type_caster<Eigen::Ref<Eigen::Vector3f,0,pybind11::EigenDStride>,void>': more than one partial specialization matches the template argument list [D:\a\pybind11\pybind11\build\tests\pybind11_tests.vcxproj]

d:\a\pybind11\pybind11\include\pybind11\detail/common.h(1023): error C2737: 'pybind11::overload_cast': 'constexpr' object must be initialized [D:\a\pybind11\pybind11\build\tests\cross_module_gil_utils.vcxproj]
d:\a\pybind11\pybind11\include\pybind11\detail/common.h(1023): error C2737: 'pybind11::overload_cast': 'constexpr' object must be initialized [D:\a\pybind11\pybind11\build\tests\pybind11_cross_module_tests.vcxproj]
d:\a\pybind11\pybind11\include\pybind11\detail/common.h(1023): error C2737: 'pybind11::overload_cast': 'constexpr' object must be initialized [D:\a\pybind11\pybind11\build\tests\pybind11_tests.vcxproj]
d:\a\pybind11\pybind11\include\pybind11\detail/common.h(1023): error C2737: 'pybind11::overload_cast': 'constexpr' object must be initialized [D:\a\pybind11\pybind11\build\tests\test_embed\external_module.vcxproj]
D:\a\pybind11\pybind11\include\pybind11\detail/common.h(624): fatal error C1001: Internal compiler error. [D:\a\pybind11\pybind11\build\tests\pybind11_tests.vcxproj]
D:\a\pybind11\pybind11\include\pybind11\detail/common.h(624): fatal error C1001: Internal compiler error. [D:\a\pybind11\pybind11\tests\pybind11_tests.vcxproj]

$ grep ': error C2737' *.txt | sed 's/^.*MSVC//' | sed 's/___.*//' | sort | uniq

_2017

$ grep ': error C2752' *.txt

3______3.8_____MSVC_2019_____x86_-DCMAKE_CXX_STANDARD=17.txt:2022-02-12T16:12:45.9921122Z D:\a\pybind11\pybind11\include\pybind11\cast.h(1364,1): error C2752: 'pybind11::detail::type_caster<Eigen::Ref<Eigen::Vector3f,0,pybind11::EigenDStride>,void>': more than one partial specialization matches the template argument list [D:\a\pybind11\pybind11\build\tests\pybind11_tests.vcxproj]

$ grep ': fatal error C1001:' *.txt

10______pypy-3.8-v7.3.7_____windows-2022_____x64.txt:2022-02-12T16:12:56.3163683Z D:\a\pybind11\pybind11\include\pybind11\detail/common.h(624): fatal error C1001: Internal compiler error. [D:\a\pybind11\pybind11\tests\pybind11_tests.vcxproj]
1______3.6_____MSVC_2019_____x86.txt:2022-02-12T16:12:47.6774625Z D:\a\pybind11\pybind11\include\pybind11\detail/common.h(624): fatal error C1001: Internal compiler error. [D:\a\pybind11\pybind11\build\tests\pybind11_tests.vcxproj]
16______3.6_____windows-latest_____x64_-DPYBIND11_FINDPYTHON=ON.txt:2022-02-12T16:12:27.0556151Z D:\a\pybind11\pybind11\include\pybind11\detail/common.h(624): fatal error C1001: Internal compiler error. [D:\a\pybind11\pybind11\tests\pybind11_tests.vcxproj]
17______3.9_____windows-2019_____x64.txt:2022-02-12T16:12:30.3822566Z D:\a\pybind11\pybind11\include\pybind11\detail/common.h(624): fatal error C1001: Internal compiler error. [D:\a\pybind11\pybind11\tests\pybind11_tests.vcxproj]
2______3.7_____MSVC_2019_____x86.txt:2022-02-12T16:12:38.7018911Z D:\a\pybind11\pybind11\include\pybind11\detail/common.h(624): fatal error C1001: Internal compiler error. [D:\a\pybind11\pybind11\build\tests\pybind11_tests.vcxproj]
6______3.6_____windows-2022_____x64.txt:2022-02-12T16:12:00.4513642Z D:\a\pybind11\pybind11\include\pybind11\detail/common.h(624): fatal error C1001: Internal compiler error. [D:\a\pybind11\pybind11\tests\pybind11_tests.vcxproj]
7______3.9_____windows-2022_____x64.txt:2022-02-12T16:11:43.6306160Z D:\a\pybind11\pybind11\include\pybind11\detail/common.h(624): fatal error C1001: Internal compiler error. [D:\a\pybind11\pybind11\tests\pybind11_tests.vcxproj]
8______3.10_____windows-2022_____x64.txt:2022-02-12T16:11:49.9589644Z D:\a\pybind11\pybind11\include\pybind11\detail/common.h(624): fatal error C1001: Internal compiler error. [D:\a\pybind11\pybind11\tests\pybind11_tests.vcxproj]
9______pypy-3.7-v7.3.7_____windows-2022_____x64.txt:2022-02-12T16:11:53.7912112Z D:\a\pybind11\pybind11\include\pybind11\detail/common.h(624): fatal error C1001: Internal compiler error. [D:\a\pybind11\pybind11\tests\pybind11_tests.vcxproj]

* common.h: is_template_base_of

* Re-applying 4 changes from 2a26873727214c5f1e159cba98f5c625b908381a that work universally.

* `overload_cast = {};` only for MSVC 2017 and Clang 5

* Refining condition for using is_template_base_of workaround.

* Undoing MSVC 2015 workaround in test_constants_and_functions.cpp

* CentOS7: silence_unused_warnings

* Tweaks in response to reviews.

* Adding windows-2022 C++20

* Trying another way of adding windows-2022 C++20

* Trying another way of adding windows-2022 C++20

* ci: try merging 2019 & 2022

* Revert "ci: try merging 2019 & 2022"

This reverts commit b158a1b79f69a43478dce5b89702858ad5952386.

Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>

* chore: drop Python 3.5 support

* chore: more fstrings with flynt's help

* ci: drop Python 3.5

* chore: bump dependency versions

* docs: touch up py::args

* tests: remove deprecation warning

* Ban smartquotes

* Very minor tweaks (by-product of reviewing PR #3719).

Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>
Co-authored-by: Ralf W. Grosse-Kunstleve <rwgk@google.com>

* `#error BYE_BYE_GOLDEN_SNAKE`

* Removing everything related to 2.7 from ci.yml

* Commenting-out Centos7

* Removing `PYTHON: 27` from .appveyor.yml

* "PY2" removal, mainly from tests. C++ code is not touched.

* Systematic removal of `u` prefix from `u"..."` and `u'...'` literals. Collateral cleanup of a couple minor other things.

* Cleaning up around case-insensitive hits for `[^a-z]py.*2` in tests/.

* Removing obsolete Python 2 mention in compiling.rst

* Proper `#error` for Python 2.

* Using PY_VERSION_HEX to guard `#error "PYTHON 2 IS NO LONGER SUPPORTED.`

* chore: bump pre-commit

* style: run pre-commit for pyupgrade 3+

* tests: use sys.version_info, not PY

* chore: more Python 2 removal

* Uncommenting Centos7 block (PR #3691 showed that it is working again).

* Update pre-commit hooks

* Fix pre-commit hook

* refactor: remove Python 2 from CMake

* refactor: remove Python 2 from setup code

* refactor: simplify, better static typing

* feat: fail with nice messages

* refactor: drop Python 2 C++ code

* docs: cleanup for Python 3

* revert: intree

revert: intree

* docs: minor touchup to py2 statement

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* chore: add clang-format

* Removing check-style (Classic check-style)

Ported from @henryiii's https://github.com/pybind/pybind11/pull/3683/commits/53056b1b0eeb4136b0d7362a8261b6b59658e0a7



* Automatic clang-format changes (NO manual changes).

Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>

* Manual line breaks to pre-empt undesired `clang-format`ing.

Informed by work under https://github.com/pybind/pybind11/pull/3683:

https://github.com/pybind/pybind11/commit/60b7eb410fefe2b23aeb6906f2a9184e91b11a15

https://github.com/pybind/pybind11/commit/59572e65598b4b9f2c9ae0b8a0e5fcb6d65c7f92

* Manual curation of clang-format diffs involving source code comments.

Very labor-intensive and dull.

* Pulling .clang-format change from @henryiii's https://github.com/pybind/pybind11/pull/3683/commits/9057962d40ca520b9d26abbe0ff125796e2323dd



* Adding commonly used .clang-format `CommentPragmas:`

* Ensure short lambdas are allowed

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