Commit Graph

26 Commits

Author SHA1 Message Date
Maarten Baert
4624e8e164
Don't return pointers to static objects with return_value_policy::take_ownership. (#3946)
* Don't return pointers to static objects with return_value_policy::take_ownership.

This fixes -Wfree-nonheap-object warnings produced by GCC.

* Use return value policy fix instead

Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>
2022-05-24 13:46:31 -04:00
Ralf W. Grosse-Kunstleve
6493f496e3
Python 2 removal part 1: tests (C++ code is intentionally ~untouched) (#3688)
* `#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

Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>
Co-authored-by: Aaron Gokaslan <skylion.aaron@gmail.com>
2022-02-10 18:28:08 -08:00
Ralf W. Grosse-Kunstleve
ec24786eab
Fully-automatic clang-format with include reordering (#3713)
* chore: add clang-format

* Removing check-style (Classic check-style)

Ported from @henryiii's 53056b1b0e

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

Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>
2022-02-10 12:17:07 -08:00
Ralf W. Grosse-Kunstleve
7769e7719c
clang-tidy readability-qualified-auto (#3702)
* Adding readability-qualified-auto to .clang-tidy

Ported from @henryiii's 287527f705

* fix: support Python < 3.6

Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>
2022-02-09 06:24:57 -08:00
Ralf W. Grosse-Kunstleve
ddbc74c674 Adding .clang-tidy readability-braces-around-statements option.
clang-tidy automatic changes. NO manual changes.
2022-02-08 13:02:20 -08:00
Henry Schreiner
39fbc7992b
fix: avoiding usage of _ if already defined (#3423)
* fix: avoid usage of _

* ci: test _ defined

* docs: include change in docs

* fix: add a test and comment

* refactor: const_str -> const_name
2021-12-21 14:24:21 -05:00
Jason Rhinelander
b4939fcbfb
Expand std::string_view support to str, bytes, memoryview (#3521)
* Expand string_view support to str, bytes, memoryview

1. Allows constructing a str or bytes implicitly from a string_view;
   this is essentially a small shortcut allowing a caller to write
   `py::bytes{sv}` rather than `py::bytes{sv.data(), sv.size()}`.

2. Allows implicit conversion *to* string_view from py::bytes -- this
   saves a fair bit more as currently there is no simple way to get such
   a view of the bytes without copying it (or resorting to Python API
   calls).

   (This is not done for `str` because when the str contains unicode we
   have to allocate to a temporary and so there might not be some string
   data we can properly view without owning.)

3. Allows `memoryview::from_memory` to accept a string_view.  As with
   the other from_memory calls, it's entirely your responsibility to
   keep it alive.

This also required moving the string_view availability detection into
detail/common.h because this PR needs it in pytypes.h, which is higher
up the include chain than cast.h where it was being detected currently.

* Move string_view include to pytypes.h

* CI-testing a fix for the "ambiguous conversion" issue.

This change is known to fix the `tensorflow::tstring` issue reported under https://github.com/pybind/pybind11/pull/3521#issuecomment-985100965

TODO: Minimal reproducer for the `tensorflow::tstring` issue.

* Make clang-tidy happy (hopefully).

* Adding minimal reproducer for the `tensorflow::tstring` issue.

Error without the enable_if trick:

```
/usr/local/google/home/rwgk/forked/pybind11/tests/test_builtin_casters.cpp:169:16: error: ambiguous conversion for functional-style cast from 'TypeWithBothOperatorStringAndStringView' to 'py::bytes'
        return py::bytes(TypeWithBothOperatorStringAndStringView());
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/local/google/home/rwgk/forked/pybind11/include/pybind11/detail/../pytypes.h:1174:5: note: candidate constructor
    bytes(const std::string &s) : bytes(s.data(), s.size()) { }
    ^
/usr/local/google/home/rwgk/forked/pybind11/include/pybind11/detail/../pytypes.h:1191:5: note: candidate constructor
    bytes(std::string_view s) : bytes(s.data(), s.size()) { }
    ^
```

* Adding missing NOLINTNEXTLINE

* Also apply ambiguous conversion workaround to str()

Co-authored-by: Ralf W. Grosse-Kunstleve <rwgk@google.com>
2021-12-03 13:20:32 -04:00
Ralf W. Grosse-Kunstleve
6abf2baa62
CodeHealth: Enabling clang-tidy google-explicit-constructor (#3250)
* Adding google-explicit-constructor to .clang-tidy

* clang-tidy explicit attr.h (all automatic)

* clang-tidy explicit cast.h (all automatic)

* clang-tidy detail/init.h (1 NOLINT)

* clang-tidy detail/type_caster_base.h (2 NOLINT)

* clang-tidy pybind11.h (7 NOLINT)

* clang-tidy detail/common.h (3 NOLINT)

* clang-tidy detail/descr.h (2 NOLINT)

* clang-tidy pytypes.h (23 NOLINT, only 1 explicit)

* clang-tidy eigen.h (7 NOLINT, 0 explicit)

* Adding 2 explicit in functional.h

* Adding 4 explicit in iostream.h

* clang-tidy numpy.h (1 NOLINT, 1 explicit)

* clang-tidy embed.h (0 NOLINT, 1 explicit)

* clang-tidy tests/local_bindings.h (0 NOLINT, 4 explicit)

* clang-tidy tests/pybind11_cross_module_tests.cpp (0 NOLINT, 1 explicit)

* clang-tidy tests/pybind11_tests.h (0 NOLINT, 2 explicit)

* clang-tidy tests/test_buffers.cpp (0 NOLINT, 2 explicit)

* clang-tidy tests/test_builtin_casters.cpp (0 NOLINT, 4 explicit)

* clang-tidy tests/test_class.cpp (0 NOLINT, 6 explicit)

* clang-tidy tests/test_copy_move.cpp (0 NOLINT, 7 explicit)

* clang-tidy tests/test_embed/external_module.cpp (0 NOLINT, 1 explicit)

* clang-tidy tests/test_embed/test_interpreter.cpp (0 NOLINT, 1 explicit)

* clang-tidy tests/object.h (0 NOLINT, 2 explicit)

* clang-tidy batch of fully automatic fixes.

* Workaround for MSVC 19.16.27045.0 C++17 Python 2 C++ syntax error.
2021-09-08 18:53:38 -07:00
Ralf W. Grosse-Kunstleve
998d45e431
Cleanup of file-scoped and globally-scoped warning suppression pragmas across pybind11 header files. (#3201)
* Removing all MSVC C4127 warning suppression pragmas.

* Removing MSVC /WX (WERROR). To get a full list of all warnings.

* Inserting PYBIND11_SILENCE_MSVC_C4127. Changing one runtime if to #if.

* Changing PYBIND11_SILENCE_MSVC_C4127 macro to use absolute namespace (for use outside pybind11 include directory).

* Restoring MSVC /WX (WERROR).

* Removing globally-scoped suppression for clang -Wunsequenced. Based on an experiment under PR #3202 it is obsolete and can simply be removed.
2021-08-19 11:37:04 -07:00
Ralf W. Grosse-Kunstleve
2d468697d9
NOLINT reduction (#3096)
* Copying from prework_no_rst branch (PR #3087): test_numpy_array.cpp, test_stl.cpp

* Manual changes reducing NOLINTs.

* clang-format-diff.py

* Minor adjustment to avoid MSVC warning C4702: unreachable code
2021-07-12 13:10:28 -07:00
Ralf W. Grosse-Kunstleve
bac5a0c370
Go all the way fixing clang-tidy issues to avoid the NOLINTNEXTLINE clutter and clang-format issues. This was really meant to be part of PR #3051 but was held back either out of an abundance of caution, or because of confusion caused by stray semicolons. (#3086) 2021-07-09 14:09:56 -07:00
Aaron Gokaslan
dac74ebdf5
fix(clang-tidy): performance fixes applied in tests and CI (#3051)
* Initial fixes

* Whoops

* Finish clang-tidy manual fixes

* Add two missing fixes

* Revert

* Update clang-tidy

* Try to fix unreachable code error

* Move nolint comment

* Apply missing fix

* Don't override clang-tidy config

* Does this fix clang-tidy?

* Make all clang-tidy errors visible

* Add comments about NOLINTs and remove a few

* Fix typo
2021-06-22 12:11:54 -04:00
Michael Kuron
48534089f7
fix: Intel ICC C++17 compatibility (#2729)
* CI: Intel icc/icpc via oneAPI

Add testing for Intel icc/icpc via the oneAPI images.
Intel oneAPI is in a late beta stage, currently shipping
oneAPI beta09 with ICC 20.2.

CI: Skip Interpreter Tests for Intel

Cannot find how to add this, neiter the package `libc6-dev` nor
`intel-oneapi-mkl-devel` help when installed to solve this:
```
-- Looking for C++ include pthread.h
-- Looking for C++ include pthread.h - not found
CMake Error at /__t/cmake/3.18.4/x64/cmake-3.18.4-Linux-x86_64/share/cmake-3.18/Modules/FindPackageHandleStandardArgs.cmake:165 (message):
  Could NOT find Threads (missing: Threads_FOUND)
Call Stack (most recent call first):
  /__t/cmake/3.18.4/x64/cmake-3.18.4-Linux-x86_64/share/cmake-3.18/Modules/FindPackageHandleStandardArgs.cmake:458 (_FPHSA_FAILURE_MESSAGE)
  /__t/cmake/3.18.4/x64/cmake-3.18.4-Linux-x86_64/share/cmake-3.18/Modules/FindThreads.cmake:234 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
  tests/test_embed/CMakeLists.txt:17 (find_package)
```

CI: libc6-dev from GCC for ICC

CI: Run bare metal for oneAPI

CI: Ubuntu 18.04 for oneAPI

CI: Intel +Catch -Eigen

CI: CMake from Apt (ICC tests)

CI: Replace Intel Py with GCC Py

CI: Intel w/o GCC's Eigen

CI: ICC with verbose make

[Debug] Find core dump

tests: use arg{} instead of arg() for Intel

tests: adding a few more missing {}

fix: sync with @tobiasleibner's branch

fix: try ubuntu 20-04

fix: drop exit 1

docs: Apply suggestions from code review

Co-authored-by: Tobias Leibner <tobias.leibner@googlemail.com>

Workaround for ICC enable_if issues

Another workaround for ICC's enable_if issues

fix error in previous commit

Disable one test for the Intel compiler in C++17 mode

Add back one instance of py::arg().noconvert()

Add NOLINT to fix clang-tidy check

Work around for ICC internal error in PYBIND11_EXPAND_SIDE_EFFECTS in C++17 mode

CI: Intel ICC with C++17

docs: pybind11/numpy.h does not require numpy at build time. (#2720)

This is nice enough to be mentioned explicitly in the docs.

docs: Update warning about Python 3.9.0 UB, now that 3.9.1 has been released (#2719)

Adjusting `type_caster<std::reference_wrapper<T>>` to support const/non-const propagation in `cast_op`. (#2705)

* Allow type_caster of std::reference_wrapper<T> to be the same as a native reference.

Before, both std::reference_wrapper<T> and std::reference_wrapper<const T> would
invoke cast_op<type>. This doesn't allow the type_caster<> specialization for T
to distinguish reference_wrapper types from value types.

After, the type_caster<> specialization invokes cast_op<type&>, which allows
reference_wrapper to behave in the same way as a native reference type.

* Add tests/examples for std::reference_wrapper<const T>

* Add tests which use mutable/immutable variants

This test is a chimera; it blends the pybind11 casters with a custom
pytype implementation that supports immutable and mutable calls.

In order to detect the immutable/mutable state, the cast_op needs
to propagate it, even through e.g. std::reference<const T>

Note: This is still a work in progress; some things are crashing,
which likely means that I have a refcounting bug or something else
missing.

* Add/finish tests that distinguish const& from &

Fixes the bugs in my custom python type implementation,
demonstrate test that requires const& and reference_wrapper<const T>
being treated differently from Non-const.

* Add passing a const to non-const method.

* Demonstrate non-const conversion of reference_wrapper in tests.

Apply formatting presubmit check.

* Fix build errors from presubmit checks.

* Try and fix a few more CI errors

* More CI fixes.

* More CI fixups.

* Try and get PyPy to work.

* Additional minor fixups. Getting close to CI green.

* More ci fixes?

* fix clang-tidy warnings from presubmit

* fix more clang-tidy warnings

* minor comment and consistency cleanups

* PyDECREF -> Py_DECREF

* copy/move constructors

* Resolve codereview comments

* more review comment fixes

* review comments: remove spurious &

* Make the test fail even when the static_assert is commented out.

This expands the test_freezable_type_caster a bit by:
1/ adding accessors .is_immutable and .addr to compare identity
from python.
2/ Changing the default cast_op of the type_caster<> specialization
to return a non-const value. In normal codepaths this is a reasonable
default.
3/ adding roundtrip variants to exercise the by reference, by pointer
and by reference_wrapper in all call paths.  In conjunction with 2/, this
demonstrates the failure case of the existing std::reference_wrpper conversion,
which now loses const in a similar way that happens when using the default cast_op_type<>.

* apply presubmit formatting

* Revert inclusion of test_freezable_type_caster

There's some concern that this test is a bit unwieldly because of the use
of the raw <Python.h> functions. Removing for now.

* Add a test that validates const references propagation.

This test verifies that cast_op may be used to correctly detect
const reference types when used with std::reference_wrapper.

* mend

* Review comments based changes.

1. std::add_lvalue_reference<type> -> type&
2. Simplify the test a little more; we're never returning the ConstRefCaster
type so the class_ definition can be removed.

* formatted files again.

* Move const_ref_caster test to builtin_casters

* Review comments: use cast_op and adjust some comments.

* Simplify ConstRefCasted test

I like this version better as it moves the assertion that matters
back into python.

ci: drop pypy2 linux, PGI 20.7, add Python 10 dev (#2724)

* ci: drop pypy2 linux, add Python 10 dev

* ci: fix mistake

* ci: commented-out PGI 20.11, drop 20.7

fix: regression with installed pybind11 overriding local one (#2716)

* fix: regression with installed pybind11 overriding discovered one

Closes #2709

* docs: wording incorrect

style: remove redundant instance->owned = true (#2723)

which was just before set to True in instance->allocate_layout()

fix: also throw in the move-constructor added by the PYBIND11_OBJECT macro, after the argument has been moved-out (if necessary) (#2701)

Make args_are_all_* ICC workarounds unconditional

Disable test_aligned on Intel ICC

Fix test_aligned on Intel ICC

Skip test_python_alreadyset_in_destructor on Intel ICC

Fix test_aligned again

ICC CI: Downgrade pytest

pytest 6 does not capture the `discard_as_unraisable` stderr and
just writes a warning with its content instead.

* refactor: simpler Intel workaround, suggested by @laramiel

* fix: try version with impl to see if it is easier to compile

* docs: update README for ICC

Co-authored-by: Axel Huebl <axel.huebl@plasma.ninja>
Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>
2021-01-17 19:53:07 -05:00
Yannick Jadoul
8449a8089c
fix: only allow integer type_caster to call __int__ method when conversion is allowed; always call __index__ (#2698)
* Only allow integer type_caster to call __int__ or __index__ method when conversion is allowed

* Remove tests for __index__ as this seems to only be used to convert to int in 3.8+

* Take both `int` and `long` types into account for Python 2

* Add test_numpy_int_convert to assert tests currently fail, even though np.intc has an __index__ method

* Also consider __index__ as noconvert to a C++ integer

* New-style classes for Python 2.7; sigh

* Add some tests on types with custom __index__ method

* Ignore some tests in Python <3.8

* Update comment about conversion from np.float32 to C++ int

* Workaround difference between CPython and PyPy's different PyIndex_Check (unnoticed because we currently don't have PyPy >= 3.8)

* Avoid ICC segfault with py::arg()
2021-01-16 20:52:14 -05:00
Axel Huebl
0b3df7f964
ci: Intel icc/icpc via oneAPI (#2573)
* CI: Intel icc/icpc via oneAPI

Add testing for Intel icc/icpc via the oneAPI images.
Intel oneAPI is in a late beta stage, currently shipping
oneAPI beta09 with ICC 20.2.

* CI: Skip Interpreter Tests for Intel

Cannot find how to add this, neiter the package `libc6-dev` nor
`intel-oneapi-mkl-devel` help when installed to solve this:
```
-- Looking for C++ include pthread.h
-- Looking for C++ include pthread.h - not found
CMake Error at /__t/cmake/3.18.4/x64/cmake-3.18.4-Linux-x86_64/share/cmake-3.18/Modules/FindPackageHandleStandardArgs.cmake:165 (message):
  Could NOT find Threads (missing: Threads_FOUND)
Call Stack (most recent call first):
  /__t/cmake/3.18.4/x64/cmake-3.18.4-Linux-x86_64/share/cmake-3.18/Modules/FindPackageHandleStandardArgs.cmake:458 (_FPHSA_FAILURE_MESSAGE)
  /__t/cmake/3.18.4/x64/cmake-3.18.4-Linux-x86_64/share/cmake-3.18/Modules/FindThreads.cmake:234 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
  tests/test_embed/CMakeLists.txt:17 (find_package)
```

* CI: libc6-dev from GCC for ICC

* CI: Run bare metal for oneAPI

* CI: Ubuntu 18.04 for oneAPI

* CI: Intel +Catch -Eigen

* CI: CMake from Apt (ICC tests)

* CI: Replace Intel Py with GCC Py

* CI: Intel w/o GCC's Eigen

* CI: ICC with verbose make

* [Debug] Find core dump

* tests: use arg{} instead of arg() for Intel

* tests: adding a few more missing {}

* fix: sync with @tobiasleibner's branch

* fix: try ubuntu 20-04

* fix: drop exit 1

* style: clang tidy fix

* style: fix missing NOLINT

* ICC: Update Compiler Name

Changed upstream with the last oneAPI release.

* ICC CI: Downgrade pytest

pytest 6 does not capture the `discard_as_unraisable` stderr and
just writes a warning with its content instead.

* Use new test pinning requirements.txt

* tests: add notes about intel, cleanup

Co-authored-by: Henry Schreiner <henryschreineriii@gmail.com>
2021-01-15 15:59:47 -05:00
Laramie Leavitt
5469c238c8
Adjusting type_caster<std::reference_wrapper<T>> to support const/non-const propagation in cast_op. (#2705)
* Allow type_caster of std::reference_wrapper<T> to be the same as a native reference.

Before, both std::reference_wrapper<T> and std::reference_wrapper<const T> would
invoke cast_op<type>. This doesn't allow the type_caster<> specialization for T
to distinguish reference_wrapper types from value types.

After, the type_caster<> specialization invokes cast_op<type&>, which allows
reference_wrapper to behave in the same way as a native reference type.

* Add tests/examples for std::reference_wrapper<const T>

* Add tests which use mutable/immutable variants

This test is a chimera; it blends the pybind11 casters with a custom
pytype implementation that supports immutable and mutable calls.

In order to detect the immutable/mutable state, the cast_op needs
to propagate it, even through e.g. std::reference<const T>

Note: This is still a work in progress; some things are crashing,
which likely means that I have a refcounting bug or something else
missing.

* Add/finish tests that distinguish const& from &

Fixes the bugs in my custom python type implementation,
demonstrate test that requires const& and reference_wrapper<const T>
being treated differently from Non-const.

* Add passing a const to non-const method.

* Demonstrate non-const conversion of reference_wrapper in tests.

Apply formatting presubmit check.

* Fix build errors from presubmit checks.

* Try and fix a few more CI errors

* More CI fixes.

* More CI fixups.

* Try and get PyPy to work.

* Additional minor fixups. Getting close to CI green.

* More ci fixes?

* fix clang-tidy warnings from presubmit

* fix more clang-tidy warnings

* minor comment and consistency cleanups

* PyDECREF -> Py_DECREF

* copy/move constructors

* Resolve codereview comments

* more review comment fixes

* review comments: remove spurious &

* Make the test fail even when the static_assert is commented out.

This expands the test_freezable_type_caster a bit by:
1/ adding accessors .is_immutable and .addr to compare identity
from python.
2/ Changing the default cast_op of the type_caster<> specialization
to return a non-const value. In normal codepaths this is a reasonable
default.
3/ adding roundtrip variants to exercise the by reference, by pointer
and by reference_wrapper in all call paths.  In conjunction with 2/, this
demonstrates the failure case of the existing std::reference_wrpper conversion,
which now loses const in a similar way that happens when using the default cast_op_type<>.

* apply presubmit formatting

* Revert inclusion of test_freezable_type_caster

There's some concern that this test is a bit unwieldly because of the use
of the raw <Python.h> functions. Removing for now.

* Add a test that validates const references propagation.

This test verifies that cast_op may be used to correctly detect
const reference types when used with std::reference_wrapper.

* mend

* Review comments based changes.

1. std::add_lvalue_reference<type> -> type&
2. Simplify the test a little more; we're never returning the ConstRefCaster
type so the class_ definition can be removed.

* formatted files again.

* Move const_ref_caster test to builtin_casters

* Review comments: use cast_op and adjust some comments.

* Simplify ConstRefCasted test

I like this version better as it moves the assertion that matters
back into python.
2020-12-15 16:53:55 -08:00
Marcin Wojdyr
8e40e389fd
cast pointer to std::tuple and std::pair (#2334) 2020-07-28 21:44:19 +02:00
Vemund Handeland
6e39b765b2 Add C++20 char8_t/u8string support (#2026)
* Fix test build in C++20

* Add C++20 char8_t/u8string support
2019-12-19 12:16:24 +01:00
Wenzel Jakob
cea42467b0
fix py::cast<void *> (#1605)
Pybind11 provides a cast operator between opaque void* pointers on the
C++ side and capsules on the Python side. The py::cast<void *>
expression was not aware of this possibility and incorrectly triggered a
compile-time assertion ("Unable to cast type to reference: value is
local to type caster") that is now fixed.
2018-11-11 19:32:09 +01:00
Henry Schreiner
cf0d0f9d5a Matching Python 2 int behavior on Python 2 (#1186)
Pybind11's default conversion to int always produces a long on Python 2 (`int`s and `long`s were unified in Python 3). This patch fixes `int` handling to match Python 2 on Python 2; for short types (`size_t` or smaller), the number will be returned as an `int` if possible, otherwise `long`. Requires Python 2.5+.

This is needed for things like `sys.exit`, which refuse to accept a `long`.
2017-11-30 13:33:24 -04:00
Jason Rhinelander
1b08df5872 Fix char & arguments being non-bindable
This changes the caster to return a reference to a (new) local `CharT`
type caster member so that binding lvalue-reference char arguments
works (currently it results in a compilation failure).

Fixes #1116
2017-10-12 09:41:54 -04:00
Ivan Smirnov
e07f75839d Implicit conversions to bool + np.bool_ conversion (#925)
This adds support for implicit conversions to bool from Python types
with `__bool__` (Python 3) or `__nonzero__` (Python 2) attributes, and
adds direct (i.e. non-converting) support for numpy bools.
2017-07-23 11:02:43 -04:00
Jason Rhinelander
b57281bb00 Use rvalue subcasting when casting an rvalue container
This updates the std::tuple, std::pair and `stl.h` type casters to
forward their contained value according to whether the container being
cast is an lvalue or rvalue reference.  This fixes an issue where
subcaster casts were always called with a const lvalue which meant
nested type casters didn't have the desired `cast()` overload invoked.
For example, this caused Eigen values in a tuple to end up with a
readonly flag (issue #935) and made it impossible to return a container
of move-only types (issue #853).

This fixes both issues by adding templated universal reference `cast()`
methods to the various container types that forward container elements
according to the container reference type.
2017-07-05 12:27:14 -04:00
Jason Rhinelander
897d71687e Combine std::tuple/std::pair logic
The std::pair caster can be written as a special case of the std::tuple
caster; this combines them via a base `tuple_caster` class (which is
essentially identical to the previous std::tuple caster).

This also removes the special empty tuple base case: returning an empty
tuple is relatively rare, and the base case still works perfectly well
even when the tuple types is an empty list.
2017-07-05 12:27:14 -04:00
Jason Rhinelander
259b2fafea Fix unsigned error value casting
When casting to an unsigned type from a python 2 `int`, we currently
cast using `(unsigned long long) PyLong_AsUnsignedLong(src.ptr())`.
If the Python cast fails, it returns (unsigned long) -1, but then we
cast this to `unsigned long long`, which means we get 4294967295, but
because that isn't equal to `(unsigned long long) -1`, we don't detect
the failure.

This commit moves the unsigned casting into a `detail::as_unsigned`
function which, upon error, casts -1 to the final type, and otherwise
casts the return value to the final type to avoid the problematic double
cast when an error occurs.

The error most commonly shows up wherever `long` is 32-bits (e.g. under
both 32- and 64-bit Windows, and under 32-bit linux) when passing a
negative value to a bound function taking an `unsigned long`.

Fixes #929.

The added tests also trigger a latent segfault under PyPy: when casting
to an integer smaller than `long` (e.g. casting to a `uint32_t` on a
64-bit `long` architecture) we check both for a Python error and also
that the resulting intermediate value will fit in the final type.  If
there is no conversion error, but we get a value that would overflow, we
end up calling `PyErr_ExceptionMatches()` illegally: that call is only
allowed when there is a current exception.  Under PyPy, this segfaults
the test suite.  It doesn't appear to segfault under CPython, but the
documentation suggests that it *could* do so.  The fix is to only check
for the exception match if we actually got an error.
2017-07-02 15:27:51 -04:00
Dean Moldovan
83e328f58c Split test_python_types.cpp into builtin_casters, stl and pytypes 2017-06-27 10:38:41 +02:00