Experiments in removing setup.py

.gitignore

@@ -53,3 +53,6 @@ htmlcov
 
 # PyCharm
 .idea
+
+# Hypothesis
+.hypothesis

CHANGES.rst

@@ -7,6 +7,8 @@
 
 * Remove support for the undocumented --compiler argument to setup.py. [#36]
 
+* Added support for enabling extension-helpers from setup.cfg. [#33]
+
 0.1 (2019-12-18)
 ----------------
 

docs/using.rst

@@ -39,3 +39,9 @@ To use this, you should modify your ``setup.py`` file to use
 Note that if you use this, extension-helpers will also we create a
 ``packagename.compiler_version`` submodule that contain information about the
 compilers used.
+
+It is also possible to enable extension-helpers in ``setup.cfg`` instead of
+``setup.py`` by adding the following configuration to the ``setup.cfg`` file::
+
+    [extension-helpers]
+    use_extension_helpers = true

extension_helpers/__init__.py

@@ -1,4 +1,21 @@
+from configparser import ConfigParser
+
 from ._openmp_helpers import add_openmp_flags_if_available
 from ._setup_helpers import get_compiler, get_extensions, pkg_config
 from ._utils import import_file, write_if_different
 from .version import version as __version__
+
+
+def _finalize_distribution_hook(distribution):
+    """
+    Entry point for setuptools which allows extension-helpers to be enabled
+    from setup.cfg without the need for setup.py.
+    """
+    config_files = distribution.find_config_files()
+    if len(config_files) == 0:
+        return
+    cfg = ConfigParser()
+    cfg.read(config_files[0])
+    if (cfg.has_option("extension-helpers", "use_extension_helpers") and
+            cfg.get("extension-helpers", "use_extension_helpers").lower() == 'true'):
+        distribution.ext_modules = get_extensions()

extension_helpers/tests/test_setup_helpers.py

@@ -1,6 +1,8 @@
 import os
 import sys
+import uuid
 import importlib
+import subprocess
 from textwrap import dedent
 
 import pytest
@@ -31,14 +33,14 @@ def _extension_test_package(tmpdir, request, extension_type='c',
     """Creates a simple test package with an extension module."""
 
     test_pkg = tmpdir.mkdir('test_pkg')
-    test_pkg.mkdir('apyhtest_eva').ensure('__init__.py')
+    test_pkg.mkdir('helpers_test_package').ensure('__init__.py')
 
     # TODO: It might be later worth making this particular test package into a
     # reusable fixture for other build_ext tests
 
     if extension_type in ('c', 'both'):
         # A minimal C extension for testing
-        test_pkg.join('apyhtest_eva', 'unit01.c').write(dedent("""\
+        test_pkg.join('helpers_test_package', 'unit01.c').write(dedent("""\
             #include <Python.h>
 
             static struct PyModuleDef moduledef = {
@@ -56,7 +58,7 @@ def _extension_test_package(tmpdir, request, extension_type='c',
 
     if extension_type in ('pyx', 'both'):
         # A minimal Cython extension for testing
-        test_pkg.join('apyhtest_eva', 'unit02.pyx').write(dedent("""\
+        test_pkg.join('helpers_test_package', 'unit02.pyx').write(dedent("""\
             print("Hello cruel angel.")
         """))
 
@@ -70,11 +72,13 @@ def _extension_test_package(tmpdir, request, extension_type='c',
     include_dirs = ['numpy'] if include_numpy else []
 
     extensions_list = [
-        "Extension('apyhtest_eva.{0}', [join('apyhtest_eva', '{1}')], include_dirs={2})".format(
+        "Extension('helpers_test_package.{0}', "
+        "[join('helpers_test_package', '{1}')], "
+        "include_dirs={2})".format(
             os.path.splitext(extension)[0], extension, include_dirs)
         for extension in extensions]
 
-    test_pkg.join('apyhtest_eva', 'setup_package.py').write(dedent("""\
+    test_pkg.join('helpers_test_package', 'setup_package.py').write(dedent("""\
         from setuptools import Extension
         from os.path import join
         def get_extensions():
@@ -89,7 +93,7 @@ def get_extensions():
         from extension_helpers import get_extensions
 
         setup(
-            name='apyhtest_eva',
+            name='helpers_test_package',
             version='0.1',
             packages=find_packages(),
             ext_modules=get_extensions()
@@ -102,7 +106,7 @@ def get_extensions():
     sys.path.insert(0, '')
 
     def finalize():
-        cleanup_import('apyhtest_eva')
+        cleanup_import('helpers_test_package')
 
     request.addfinalizer(finalize)
 
@@ -169,11 +173,107 @@ def test_compiler_module(capsys, c_extension_test_package):
                    '--record={0}'.format(install_temp.join('record.txt'))])
 
     with install_temp.as_cwd():
-        import apyhtest_eva
+        import helpers_test_package
 
-        # Make sure we imported the apyhtest_eva package from the correct place
-        dirname = os.path.abspath(os.path.dirname(apyhtest_eva.__file__))
-        assert dirname == str(install_temp.join('apyhtest_eva'))
+        # Make sure we imported the helpers_test_package package from the correct place
+        dirname = os.path.abspath(os.path.dirname(helpers_test_package.__file__))
+        assert dirname == str(install_temp.join('helpers_test_package'))
 
-        import apyhtest_eva.compiler_version
-        assert apyhtest_eva.compiler_version != 'unknown'
+        import helpers_test_package.compiler_version
+        assert helpers_test_package.compiler_version != 'unknown'
+
+
+@pytest.mark.parametrize('use_extension_helpers', [None, False, True])
+def test_no_setup_py(tmpdir, use_extension_helpers):
+    """
+    Test that makes sure that extension-helpers can be enabled without a
+    setup.py file.
+    """
+
+    package_name = 'helpers_test_package_' + str(uuid.uuid4()).replace('-', '_')
+
+    test_pkg = tmpdir.mkdir('test_pkg')
+    test_pkg.mkdir(package_name).ensure('__init__.py')
+
+    simple_c = test_pkg.join(package_name, 'simple.c')
+
+    simple_c.write(dedent("""\
+        #include <Python.h>
+
+        static struct PyModuleDef moduledef = {
+            PyModuleDef_HEAD_INIT,
+            "simple",
+            NULL,
+            -1,
+            NULL
+        };
+        PyMODINIT_FUNC
+        PyInit_simple(void) {
+            return PyModule_Create(&moduledef);
+        }
+    """))
+
+    test_pkg.join(package_name, 'setup_package.py').write(dedent(f"""\
+        from setuptools import Extension
+        from os.path import join
+        def get_extensions():
+            return [Extension('{package_name}.simple', [join('{package_name}', 'simple.c')])]
+        """))
+
+    if use_extension_helpers is None:
+        test_pkg.join('setup.cfg').write(dedent(f"""\
+            [metadata]
+            name = {package_name}
+            version = 0.1
+
+            [options]
+            packages = find:
+        """))
+    else:
+        test_pkg.join('setup.cfg').write(dedent(f"""\
+            [metadata]
+            name = {package_name}
+            version = 0.1
+
+            [options]
+            packages = find:
+
+            [extension-helpers]
+            use_extension_helpers = {str(use_extension_helpers).lower()}
+        """))
+
+    test_pkg.join('pyproject.toml').write(dedent("""\
+        [build-system]
+        requires = ["setuptools>=43.0.0",
+                    "wheel"]
+        build-backend = 'setuptools.build_meta'
+    """))
+
+    install_temp = test_pkg.mkdir('install_temp')
+
+    with test_pkg.as_cwd():
+        # NOTE: we disable build isolation as we need to pick up the current
+        # developer version of extension-helpers
+        subprocess.call([sys.executable, '-m', 'pip', 'install', '.',
+                         '--no-build-isolation',
+                         f'--target={install_temp}'])
+
+    if '' in sys.path:
+        sys.path.remove('')
+
+    sys.path.insert(0, '')
+
+    with install_temp.as_cwd():
+
+        importlib.import_module(package_name)
+
+        if use_extension_helpers:
+            compiler_version_mod = importlib.import_module(package_name + '.compiler_version')
+            assert compiler_version_mod.compiler != 'unknown'
+        else:
+            try:
+                importlib.import_module(package_name + '.compiler_version')
+            except ImportError:
+                pass
+            else:
+                raise AssertionError(package_name + '.compiler_version should not exist')

setup.cfg

@@ -30,6 +30,10 @@ install_requires =
 [options.package_data]
 extension_helpers = src/compiler.c
 
+[options.entry_points]
+setuptools.finalize_distribution_options =
+    extension_helpers_get_extensions = extension_helpers:_finalize_distribution_hook
+
 [options.extras_require]
 test =
     pytest

tox.ini

@@ -13,7 +13,7 @@ passenv =
     CONDA_BUILD_SYSROOT
 setenv =
     osxclang: CC=clang-10
-    linuxgcc: CC=x86_64-conda_cos6-linux-gnu-gcc
+    linuxgcc: CC=gcc_linux-64
 changedir =
     test: .tmp/{envname}
     build_docs: docs
@@ -31,13 +31,14 @@ conda_deps =
     osxclang: clang_osx-64==10
     osxclang: llvm-openmp
     linuxgcc: gcc_linux-64
+conda_channels =
+    linuxgcc: conda-forge
 extras =
     test: test
     build_docs: docs
     all: all
 commands =
-    dev: bash -ec "rm -rf setuptools_repo; git clone https://github.com/pypa/setuptools.git setuptools_repo && cd setuptools_repo && python bootstrap.py"
-    dev: pip install setuptools_repo/ --no-build-isolation
+    dev: pip install git+https://github.com/pypa/setuptools.git
     pip freeze
     test: python -c 'import setuptools; print(setuptools.__version__)'
     test: pytest --pyargs extension_helpers {toxinidir}/docs --cov extension_helpers --cov-config={toxinidir}/setup.cfg {posargs}