Add pyproject-srpm-macros with a minimal %pyproject_buildrequires macro

pyproject-srpm-macros is intended to be installed in the default buildroot.

That way, no explicit BuildRequires for pyproject-rpm-macros are required,
as long as %pyproject_buildrequires is used in %generate_buildrequires.

When only pyproject-srpm-macros is installed, the minimal implementation of
%pyproject_buildrequires generates a dependency on pyproject-rpm-macros.
When pyproject-rpm-macros is installed, it overrides the implementation
of %pyproject_buildrequires with the full one.

Note that in Fedora, pyproject-rpm-macros is required by python3-devel,
but not in RHEL.
This allows us to keep pyproject-rpm-macros in the RHEL CRB repository.

macros.aaa-pyproject-srpm

@@ -0,0 +1,7 @@
+# This file is called macros.aaa-pyproject-srpm
+# to sort alphabetically before macros.pyproject.
+# When this file is installed but macros.pyproject is not
+# this macro will cause the package with the real macro to be installed.
+# When macros.pyproject is installed, it overrides this macro.
+# Note: This needs to maintain the same set of options as the real macro.
+%pyproject_buildrequires(rRxtNwe:) echo 'pyproject-rpm-macros' && exit 0

macros.pyproject

@@ -124,6 +124,7 @@ fi
 %toxenv %{default_toxenv}
 
 
+# Note: Keep the options in sync with this macro from macros.aaa-pyproject-srpm
 %pyproject_buildrequires(rRxtNwe:) %{expand:\\\
 %_set_pytest_addopts
 # The _auto_set_build_flags feature does not do this in %%generate_buildrequires section,
@@ -144,7 +145,7 @@ fi
 %{-w:%{error:The -N and -w options are mutually exclusive}}
 }
 %{-e:%{expand:%global toxenv %(%{__python3} -s %{_rpmconfigdir}/redhat/pyproject_construct_toxenv.py %{?**})}}
-echo 'pyproject-rpm-macros'  # we already have this installed, but this way, it's repoqueryable
+echo 'pyproject-rpm-macros'  # first stdout line matches the implementation in macros.aaa-pyproject-srpm
 echo 'python%{python3_pkgversion}-devel'
 echo 'python%{python3_pkgversion}dist(pip) >= 19'
 echo 'python%{python3_pkgversion}dist(packaging)'

pyproject-rpm-macros.spec

@@ -10,11 +10,12 @@ License:        MIT
 #   Increment Y and reset Z when new macros or features are added
 #   Increment Z when this is a bugfix or a cosmetic change
 # Dropping support for EOL Fedoras is *not* considered a breaking change
-Version:        1.5.1
-Release:        2%{?dist}
+Version:        1.6.0
+Release:        1%{?dist}
 
 # Macro files
 Source001:      macros.pyproject
+Source002:      macros.aaa-pyproject-srpm
 
 # Implementation files
 Source101:      pyproject_buildrequires.py
@@ -62,6 +63,7 @@ BuildRequires:  python3-rpm-macros
 Requires:       python-rpm-macros
 Requires:       python-srpm-macros
 Requires:       python3-rpm-macros
+Requires:       (pyproject-srpm-macros = %{?epoch:%{epoch}:}%{version}-%{release} if pyproject-srpm-macros)
 
 # We use the following tools outside of coreutils
 Requires:       /usr/bin/find
@@ -82,6 +84,17 @@ These macros replace %%py3_build and %%py3_install,
 which only work with setup.py.
 
 
+%package -n pyproject-srpm-macros
+Summary:        Minimal implementation of %%pyproject_buildrequires
+Requires:       (pyproject-rpm-macros = %{?epoch:%{epoch}:}%{version}-%{release} if pyproject-rpm-macros)
+
+%description -n pyproject-srpm-macros
+This package contains a minimal implementation of %%pyproject_buildrequires.
+When used in %%generate_buildrequires, it will generate BuildRequires
+for pyproject-rpm-macros. When both packages are installed, the full version
+takes precedence.
+
+
 %prep
 # Not strictly necessary but allows working on file names instead
 # of source numbers in install section
@@ -95,6 +108,7 @@ cp -p %{sources} .
 mkdir -p %{buildroot}%{_rpmmacrodir}
 mkdir -p %{buildroot}%{_rpmconfigdir}/redhat
 install -pm 644 macros.pyproject %{buildroot}%{_rpmmacrodir}/
+install -pm 644 macros.aaa-pyproject-srpm %{buildroot}%{_rpmmacrodir}/
 install -pm 644 pyproject_buildrequires.py %{buildroot}%{_rpmconfigdir}/redhat/
 install -pm 644 pyproject_convert.py %{buildroot}%{_rpmconfigdir}/redhat/
 install -pm 644 pyproject_save_files.py  %{buildroot}%{_rpmconfigdir}/redhat/
@@ -126,7 +140,15 @@ export HOSTNAME="rpmbuild"  # to speedup tox in network-less mock, see rhbz#1856
 %doc README.md
 %license LICENSE
 
+%files -n pyproject-srpm-macros
+%{_rpmmacrodir}/macros.aaa-pyproject-srpm
+%license LICENSE
+
+
 %changelog
+* Fri Jan 20 2023 Miro Hrončok <miro@hroncok.cz> - 1.6.0-1
+- Add pyproject-srpm-macros with a minimal %%pyproject_buildrequires macro
+
 * Fri Jan 20 2023 Fedora Release Engineering <releng@fedoraproject.org> - 1.5.1-2
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_38_Mass_Rebuild
 

tests/python-entrypoints.spec

@@ -8,12 +8,13 @@ URL:            https://entrypoints.readthedocs.io/
 Source0:        %{pypi_source}
 
 BuildArch:      noarch
-BuildRequires:  pyproject-rpm-macros
-BuildRequires:  python3-devel
 
 %description
 This package contains one .py module
 Building this tests the flit build backend.
+This package also has no explicit BuildRequires for python or the macros,
+testing the minimal implementation of %%pyproject_buildrequires
+from pyproject-srpm-macros.
 
 
 %package -n python3-%{pypi_name}