add support for noconvert

[nbecker]

No description provided.

[nbecker]

Should probably add a test, but I'm not familiar with the codebase

[JohanMabille]

xtensor-python is built with cmake:

• the CMakeLists.txt file at the root of the project contains, among other things, the lists oth the headers:

set(XTENSOR_PYTHON_HEADERS ${XTENSOR_PYTHON_INCLUDE_DIR}/xtensor-python/pyarray.hpp ${XTENSOR_PYTHON_INCLUDE_DIR}/xtensor-python/pybuffer_adaptor.hpp ${XTENSOR_PYTHON_INCLUDE_DIR}/xtensor-python/pycontainer.hpp ${XTENSOR_PYTHON_INCLUDE_DIR}/xtensor-python/pytensor.hpp ${XTENSOR_PYTHON_INCLUDE_DIR}/xtensor-python/pyvectorize.hpp ${XTENSOR_PYTHON_INCLUDE_DIR}/xtensor-python/xtensor_python_config.hpp )

Each time you add a header to the project, you must update this list.

• test/CMakeLists.txt contains the instructions to build the pure C++ tests (no python involved). Among them, you have the lists of source files:

set(XTENSOR_PYTHON_TESTS main.cpp test_pyarray.cpp test_pytensor.cpp test_pyvectorize.cpp )

As for headers, every new cpp test file should be added to this list. Tests rely on gtest, having a look at test/test_pytensor.cpp should show you how to do your own test.

• test/test_python contains the python tests, you can run them with py.test. You can add your C++ code to the main.cpp file, and then update test_pyarray.py to add python tests.

[JohanMabille]

I don't think you need to add the file pytraits.hpp, numpy_traits is already provided by xtensor-python in the file pycontainer.hpp.

[nbecker]

If we add a test for noconvert, we should expect a testcase that will raise an exception. I didn't see any example of this type of test in the current test directory.

[JohanMabille]

Indeed, I think you could rely on numpy.testing.assert_raises; I think pybind11 throws a cast_error when pyobject_caster<XXX>::load fails, but not sure about that.

[JohanMabille]

Fixed in #87.