add virtualenv subpkg

python-build.spec

@@ -4,6 +4,8 @@
 #
 # SPDX-License-Identifier: MulanPSL-2.0
 
+%global extras 1
+
 %global srcname build
 
 Name:           python-%{srcname}
@@ -28,8 +30,10 @@ build a distribution package.  It is a simple build tool and does not perform
 any dependency management.  It aims to keep dependencies to a minimum, in
 order to make bootstrapping easier.
 
+%pyproject_extras_subpkg -n python-build virtualenv
+
 %generate_buildrequires
-%pyproject_buildrequires
+%pyproject_buildrequires "-x virtualenv"
 
 %files -f %{pyproject_files}
 %doc README*