bootstrap_image and the local repositories

We can not use user_mountpoints because these aren't (historically, not
sure what are the reasons) mounted too late during the Buildroot
preparation (after the self._init_pkg_management()).  This isn't
actually an issue when 'use_bootstrap_image == False' because we use the
package manager on host (so it actually sees the repository on host).

So newly we place the local_repo mount points into the "managed"
category, which seems even semantically better now.  We though need to
call the 'self.mounts.mountall_managed()' method a little bit later than
before, when the local repo BindMountPoints are already defined by
self.pkg_manager.initialize().

This problem has been triggered by the LVM test-case that creates a
custom local_repo (on host) with `baseurl=/tmp/foo` that needs to be
bind-mounted into the bootstrap chroot properly.

Closes: #1167

mock/py/mockbuild/buildroot.py

@@ -241,14 +241,18 @@ def _init(self, prebuild):
         self._setup_devices()
 
         self._setup_files()
-        self.mounts.mountall_managed()
 
         # write out config details
         self.root_log.debug('rootdir = %s', self.make_chroot_path())
         self.root_log.debug('resultdir = %s', self.resultdir)
 
         self.set_package_manager()
+
+        # this creates some managed mounts
         self.pkg_manager.initialize()
+
+        self.mounts.mountall_managed()
+
         self._setup_resolver_config()
         self._setup_katello_ca()
 

mock/py/mockbuild/package_manager.py

@@ -476,9 +476,19 @@ def _bind_mount_repos_to_bootstrap(self):
                     bind_mount_point = BindMountPoint(srcpath=srcpath,
                                                       bindpath=bindpath)
 
-                    # we need to use user mounts as essential mounts are used
-                    # only for installing into bootstrap chroot
-                    self.buildroot.mounts.add_user_mount(bind_mount_point)
+                    # This is a very tricky hack.  Note we configure the
+                    # package_manager for the "bootstrap" chroot here, but these
+                    # "local repo" mountpoints are actually needed by both
+                    # "bootstrap" and "build" chroots.  The "bootstrap" chroot
+                    # needs this with the 'bootstrap_image' feature (we use
+                    # package manager _in bootstrap_, not on host, to install
+                    # into the bootstrap) and the "build" chroot package manager
+                    # always needs this (but also mounted in bootstrap).  That's
+                    # why we are not using "essential mounts"; these are only
+                    # automatically mounted by the corresponding package manager
+                    # (we wouldn't mount bootstrap's mountpoints when installing
+                    # into the "build" chroot).
+                    self.buildroot.mounts.add(bind_mount_point)
 
     def initialize_config(self):
         # there may be configs we get from container image

mock/tests/test_package_manager.py

@@ -79,7 +79,7 @@ def get_user_bind_mounts_from_config(self, config):
         pm.pkg_manager_config = config
         pm.initialize_config()
         pm._bind_mount_repos_to_bootstrap()
-        return self.bootstrap_buildroot.mounts.user_mounts
+        return self.bootstrap_buildroot.mounts.managed_mounts
 
     def test_absolute_path_name_in_baseurl(self):
         repo_directory = os.path.join(self.workdir, 'repo')