improve typing

linuxnamespaces/__init__.py:
 * linuxnamespaces.filedescriptor only exports FileDescriptor. By
   importing *, we re-export it implicitly.

linuxnamespaces/atlocation.py:
 * PathLike should be parameterized and we no longer allow bytes there.

linuxnamespaces/tarutils.py:
 * Resolve dict vs Mapping.

tests/test_simple.py:
 * Establish expected type to mypy.

examples/unschroot.py:
 * pidfd is first an int and later a FileDescriptor, but we always use
   it as int.
 * Also tell mypy that we cannot get NULL from waitid.

1 files changed, 4 insertions, 1 deletions

diff --git a/examples/unschroot.py b/examples/unschroot.py
index 682b5b0..5f644fc 100755
--- a/examples/unschroot.py
+++ b/examples/unschroot.py
@@ -207,6 +207,7 @@ def do_run_session(args: argparse.Namespace) -> None:
     gidmap = linuxnamespaces.IDAllocation.loadsubid("gid").allocatemap(65536)
     mainsock, childsock = socket.socketpair()
     pid = os.fork()
+    pidfd: int
     if pid == 0:
         mainsock.close()
         os.chdir(session.path)
@@ -281,7 +282,9 @@ def do_run_session(args: argparse.Namespace) -> None:
     os.waitpid(pid, 0)
     linuxnamespaces.prctl_set_child_subreaper(False)
     mainsock.send(b"\0")
-    sys.exit(os.waitid(os.P_PIDFD, pidfd, os.WEXITED).si_status)
+    wres = os.waitid(os.P_PIDFD, pidfd, os.WEXITED)
+    assert wres is not None
+    sys.exit(wres.si_status)
 
 
 def do_end_session(args: argparse.Namespace) -> None: