Adding tests for xtensor-python

Author: SylvainCorlay

.gitignore

@@ -0,0 +1,28 @@
+# Python Artefacts
+
+*.py[cod]
+
+# C extensions
+
+*.so
+
+# Packages
+
+*.egg
+*.egg-info
+dist
+build
+eggs
+parts
+bin
+var
+sdist
+develop-eggs
+.installed.cfg
+lib
+lib64
+__pycache__
+tmp/
+
+# Jupyter Artefacts
+.ipynb_checkpoints/

README.md

@@ -13,4 +13,10 @@
 
 # Testing
 
- - Checkout and pip install the `xtensor-python-test` project.
+  Testing `xtensor-python` requires `nosetests`
+
+  ``` bash
+  nosetests .
+  ```
+
+  To pick up changes in `xtensor-python` while rebuilding, delete the `build/` directory. 

test/main.cpp

@@ -0,0 +1,19 @@
+#include <pybind11/pybind11.h>
+#include "xtensor/xarray.hpp"
+#include "xtensor-python/pyarray.hpp"
+
+namespace py = pybind11;
+
+int test0(xt::pyarray<double> &m)
+{
+    return m(0);
+}
+
+PYBIND11_PLUGIN(xtensor_python_test)
+{
+    py::module m("xtensor_python_test", "Test module for xtensor python bindings");
+
+    m.def("test0", test0, "");
+
+    return m.ptr();
+}

test/setup.py

@@ -0,0 +1,100 @@
+from setuptools import setup, Extension
+from setuptools.command.build_ext import build_ext
+import sys
+import os
+import setuptools
+
+__version__ = '0.0.1'
+
+
+class get_pybind_include(object):
+    """Helper class to determine the pybind11 include path
+
+    The purpose of this class is to postpone importing pybind11
+    until it is actually installed, so that the ``get_include()``
+    method can be invoked. """
+
+    def __init__(self, user=False):
+        self.user = user
+
+    def __str__(self):
+        import pybind11
+        return pybind11.get_include(self.user)
+
+
+ext_modules = [
+    Extension(
+        'xtensor_python_test',
+        ['main.cpp'],
+        include_dirs=[
+            # Path to pybind11 headers
+            get_pybind_include(),
+            get_pybind_include(user=True),
+            os.path.join(sys.prefix, 'include')
+        ],
+        language='c++'
+    ),
+]
+
+
+def has_flag(compiler, flagname):
+    """Return a boolean indicating whether a flag name is supported on
+    the specified compiler.
+    """
+    import tempfile
+    with tempfile.NamedTemporaryFile('w', suffix='.cpp') as f:
+        f.write('int main (int argc, char **argv) { return 0; }')
+        try:
+            compiler.compile([f.name], extra_postargs=[flagname])
+        except setuptools.distutils.errors.CompileError:
+            return False
+    return True
+
+
+def cpp_flag(compiler):
+    """Return the -std=c++14 compiler flag  and errors when the flag is
+    no available.
+    """
+    if has_flag(compiler, '-std=c++14'):
+        return '-std=c++14'
+    else:
+        raise RuntimeError('C++14 support is required by xtensor!')
+
+
+class BuildExt(build_ext):
+    """A custom build extension for adding compiler-specific options."""
+    c_opts = {
+        'msvc': ['/EHsc'],
+        'unix': [],
+    }
+
+    if sys.platform == 'darwin':
+        c_opts['unix'] += ['-stdlib=libc++', '-mmacosx-version-min=10.7']
+
+    def build_extensions(self):
+        ct = self.compiler.compiler_type
+        opts = self.c_opts.get(ct, [])
+        if ct == 'unix':
+            opts.append('-DVERSION_INFO="%s"' % self.distribution.get_version())
+            opts.append(cpp_flag(self.compiler))
+            if has_flag(self.compiler, '-fvisibility=hidden'):
+                opts.append('-fvisibility=hidden')
+        elif ct == 'msvc':
+            opts.append('/DVERSION_INFO=\\"%s\\"' % self.distribution.get_version())
+        for ext in self.extensions:
+            ext.extra_compile_args = opts
+        build_ext.build_extensions(self)
+
+setup(
+    name='xtensor_python_test',
+    version=__version__,
+    author='Sylvain Corlay',
+    author_email='sylvain.corlay@gmail.com',
+    url='https://github.com/pybind/python_example',
+    description='An example project using xtensor-python',
+    long_description='',
+    ext_modules=ext_modules,
+    install_requires=['pybind11>=1.8.1'],
+    cmdclass={'build_ext': BuildExt},
+    zip_safe=False,
+)

test/test_pyarray.py

@@ -0,0 +1,18 @@
+import os
+import sys
+import subprocess
+
+# Build the test extension
+
+here = os.path.abspath(os.path.dirname(__file__))
+subprocess.check_call([sys.executable, os.path.join(here, 'setup.py'), 'build_ext', '--inplace'], cwd=here)
+
+# Test it!
+
+from unittest import TestCase
+import xtensor_python_test as xt
+
+class ExampleTest(TestCase):
+
+    def test_example(self):
+        self.assertEqual(4, xt.test0([4, 5, 6]))