Reset the dnf base when clearing cache

To reset the repo sack, the whole base must be created anew, because it
is not possible to lead repositories multiple times in dnf5.

Author: pkratoch

pyanaconda/modules/payloads/payload/dnf/dnf_manager.py

@@ -541,8 +541,7 @@ def clear_cache(self):
         shutil.rmtree(DNF_CACHE_DIR, ignore_errors=True)
         shutil.rmtree(DNF_PLUGINCONF_DIR, ignore_errors=True)
 
-        # FIXME: Reset sacks. Should we just drop the base?
-        # self._base.reset(sack=True, repos=True, goal=True)
+        self.reset_base()
 
         log.debug("The DNF cache has been cleared.")
 

tests/unit_tests/pyanaconda_tests/modules/payloads/payload/test_module_payload_dnf5_manager.py

@@ -995,10 +995,10 @@ def test_read_system_repositories(self):
         with pytest.raises(RuntimeError):
             self.dnf_manager.read_system_repositories()
 
-        # FIXME: Unless we cleared the cache.
-        # self.dnf_manager.clear_cache()
-        # assert not self.dnf_manager._enabled_system_repositories
-        # self.dnf_manager.read_system_repositories()
+        # Unless we cleared the cache.
+        self.dnf_manager.clear_cache()
+        assert not self.dnf_manager._enabled_system_repositories
+        self.dnf_manager.read_system_repositories()
 
         # Or reset the base.
         self.dnf_manager.reset_base()