numpy/distutils/tests/test_build_ext.py

'''Tests for numpy.distutils.build_ext.'''

import os
import subprocess
import sys
from textwrap import indent, dedent
import pytest

@pytest.mark.slow
def test_multi_fortran_libs_link(tmp_path):
    '''
    Ensures multiple "fake" static libraries are correctly linked.
    see gh-18295
    '''

    # We need to make sure we actually have an f77 compiler.
    # This is nontrivial, so we'll borrow the utilities
    # from f2py tests:
    from numpy.f2py.tests.util import has_f77_compiler
    if not has_f77_compiler():
        pytest.skip('No F77 compiler found')

    # make some dummy sources
    with open(tmp_path / '_dummy1.f', 'w') as fid:
        fid.write(indent(dedent('''\
            FUNCTION dummy_one()
            RETURN
            END FUNCTION'''), prefix=' '*6))
    with open(tmp_path / '_dummy2.f', 'w') as fid:
        fid.write(indent(dedent('''\
            FUNCTION dummy_two()
            RETURN
            END FUNCTION'''), prefix=' '*6))
    with open(tmp_path / '_dummy.c', 'w') as fid:
        # doesn't need to load - just needs to exist
        fid.write('int PyInit_dummyext;')

    # make a setup file
    with open(tmp_path / 'setup.py', 'w') as fid:
        srctree = os.path.join(os.path.dirname(__file__), '..', '..', '..')
        fid.write(dedent(f'''\
            def configuration(parent_package="", top_path=None):
                from numpy.distutils.misc_util import Configuration
                config = Configuration("", parent_package, top_path)
                config.add_library("dummy1", sources=["_dummy1.f"])
                config.add_library("dummy2", sources=["_dummy2.f"])
                config.add_extension("dummyext", sources=["_dummy.c"], libraries=["dummy1", "dummy2"])
                return config


            if __name__ == "__main__":
                import sys
                sys.path.insert(0, r"{srctree}")
                from numpy.distutils.core import setup
                setup(**configuration(top_path="").todict())'''))

    # build the test extensino and "install" into a temporary directory
    build_dir = tmp_path
    subprocess.check_call([sys.executable, 'setup.py', 'build', 'install',
                           '--prefix', str(tmp_path / 'installdir'),
                           '--record', str(tmp_path / 'tmp_install_log.txt'),
                          ],
                          cwd=str(build_dir),
                      )
    # get the path to the so
    so = None
    with open(tmp_path /'tmp_install_log.txt') as fid:
        for line in fid:
            if 'dummyext' in line:
                so = line.strip()
                break
    assert so is not None