Expose the environment variables used by %pytest via %{py3_test_envvars}

This way, we will be able to reuse them in %tox from pyproject-rpm-macros.
Packagers will be able to use them in their spec files.

See https://lists.fedoraproject.org/archives/list/python-devel@lists.fedoraproject.org/thread/A3QQSHP5OSLIVMCL52AR2GRBRXYQHU6B/

macros.python

@@ -131,6 +131,16 @@
   end
 }
 
+# Environment variables for testing used standalone, e.g.:
+#  %%{py_test_envvars} %%{python} -m unittest
+%py_test_envvars %{expand:\\\
+  CFLAGS="${CFLAGS:-${RPM_OPT_FLAGS}}" LDFLAGS="${LDFLAGS:-${RPM_LD_FLAGS}}"\\\
+  PATH="%{buildroot}%{_bindir}:$PATH"\\\
+  PYTHONPATH="${PYTHONPATH:-%{buildroot}%{python_sitearch}:%{buildroot}%{python_sitelib}}"\\\
+  PYTHONDONTWRITEBYTECODE=1\\\
+  %{?__pytest_addopts:PYTEST_ADDOPTS="${PYTEST_ADDOPTS:-} %{__pytest_addopts}"}\\\
+  PYTEST_XDIST_AUTO_NUM_WORKERS=%{_smp_build_ncpus}}
+
 %python_disable_dependency_generator() \
 %undefine __pythondist_requires \
 %{nil}

macros.python3

@@ -105,13 +105,16 @@
   end
 }
 
-# This is intended for Python 3 only, hence also no Python version in the name.
-%__pytest /usr/bin/pytest%(test %{python3_pkgversion} == 3 || echo -%{python3_version})
-%pytest %{expand:\\\
+# Environment variables used by %%pytest, %%tox or standalone, e.g.:
+#  %%{py3_test_envvars} %%{python3} -m unittest
+%py3_test_envvars %{expand:\\\
   CFLAGS="${CFLAGS:-${RPM_OPT_FLAGS}}" LDFLAGS="${LDFLAGS:-${RPM_LD_FLAGS}}"\\\
   PATH="%{buildroot}%{_bindir}:$PATH"\\\
   PYTHONPATH="${PYTHONPATH:-%{buildroot}%{python3_sitearch}:%{buildroot}%{python3_sitelib}}"\\\
   PYTHONDONTWRITEBYTECODE=1\\\
   %{?__pytest_addopts:PYTEST_ADDOPTS="${PYTEST_ADDOPTS:-} %{__pytest_addopts}"}\\\
-  PYTEST_XDIST_AUTO_NUM_WORKERS=%{_smp_build_ncpus}\\\
-  %__pytest}
+  PYTEST_XDIST_AUTO_NUM_WORKERS=%{_smp_build_ncpus}}
+
+# This is intended for Python 3 only, hence also no Python version in the name.
+%__pytest /usr/bin/pytest%(test %{python3_pkgversion} == 3 || echo -%{python3_version})
+%pytest %py3_test_envvars %__pytest

python-rpm-macros.spec

@@ -162,6 +162,7 @@ grep -E '^#[^%%]*%%[^%%]' %{buildroot}%{rpmmacrodir}/macros.* && exit 1 || true
 * Sun Nov 13 2022 Miro Hrončok <mhroncok@redhat.com> - 3.11-6
 - Set PYTEST_XDIST_AUTO_NUM_WORKERS=%%{_smp_build_ncpus} from %%pytest
 - pytest-xdist 3+ respects this value when -n auto is used
+- Expose the environment variables used by %%pytest via %%{py3_test_envvars}
 
 * Tue Oct 25 2022 Lumír Balhar <lbalhar@redhat.com> - 3.11-5
 - Include pathfix.py in this package

tests/test_evals.py

@@ -357,6 +357,28 @@ def test_pytest_addopts_preserves_envvar(__pytest_addopts):
     assert 'z--' not in echoed
 
 
+@pytest.mark.parametrize('__pytest_addopts', ['-X', None])
+def test_py3_test_envvars(lib, __pytest_addopts):
+    lines = rpm_eval('%{py3_test_envvars}\\\n%{python3} -m unittest',
+                     buildroot='BUILDROOT',
+                     _smp_build_ncpus='3',
+                     __pytest_addopts=__pytest_addopts)
+    assert all(l.endswith('\\') for l in lines[:-1])
+    stripped_lines = [l.strip(' \\') for l in lines]
+    sitearch = f'BUILDROOT/usr/{lib}/python{X_Y}/site-packages'
+    sitelib = f'BUILDROOT/usr/lib/python{X_Y}/site-packages'
+    assert f'PYTHONPATH="${{PYTHONPATH:-{sitearch}:{sitelib}}}"' in stripped_lines
+    assert 'PATH="BUILDROOT/usr/bin:$PATH"' in stripped_lines
+    assert 'CFLAGS="${CFLAGS:-${RPM_OPT_FLAGS}}" LDFLAGS="${LDFLAGS:-${RPM_LD_FLAGS}}"' in stripped_lines
+    assert 'PYTHONDONTWRITEBYTECODE=1' in stripped_lines
+    assert 'PYTEST_XDIST_AUTO_NUM_WORKERS=3' in stripped_lines
+    if __pytest_addopts:
+        assert f'PYTEST_ADDOPTS="${{PYTEST_ADDOPTS:-}} {__pytest_addopts}"' in stripped_lines
+    else:
+        assert 'PYTEST_ADDOPTS' not in ''.join(lines)
+    assert stripped_lines[-1] == '/usr/bin/python3 -m unittest'
+
+
 def test_pypi_source_default_name():
     urls = rpm_eval('%pypi_source',
                     name='foo', version='6')
@@ -691,6 +713,7 @@ unversioned_macros = pytest.mark.parametrize('macro', [
     '%py_install_egg',
     '%py_install_wheel',
     '%py_check_import',
+    '%py_test_envvars',
 ])