treewide: adopt pathlib.Path and type hinting (MR 2252)

With the new chroot type, we can now write fancy paths in the pythonic
way. Convert most of the codebase over, as well as adding various other
type hints.

Signed-off-by: Caleb Connolly <caleb@postmarketos.org>

pmb/helpers/logging.py

@@ -3,15 +3,29 @@
 import logging
 import os
 import sys
+from typing import TextIO
 import pmb.config
 from pmb.core.types import PmbArgs
 
-logfd = None
+logfd: TextIO
 
+CRITICAL = logging.CRITICAL
+FATAL = logging.FATAL
+ERROR = logging.ERROR
+WARNING = logging.WARNING
+WARN = logging.WARN
+INFO = logging.INFO
+DEBUG = logging.DEBUG
+NOTSET = logging.NOTSET
+VERBOSE = 5
 
 class log_handler(logging.StreamHandler):
     """Write to stdout and to the already opened log file."""
-    _args = None
+    _args: PmbArgs
+    
+    def __init__(self, args: PmbArgs):
+        super().__init__()
+        self._args = args
 
     def emit(self, record):
         try:
@@ -80,13 +94,13 @@ def add_verbose_log_level():
     All stackoverflow user contributions are licensed as CC-BY-SA:
     https://creativecommons.org/licenses/by-sa/3.0/
     """
-    logging.VERBOSE = 5
-    logging.addLevelName(logging.VERBOSE, "VERBOSE")
-    logging.Logger.verbose = lambda inst, msg, * \
-        args, **kwargs: inst.log(logging.VERBOSE, msg, *args, **kwargs)
-    logging.verbose = lambda msg, *args, **kwargs: logging.log(logging.VERBOSE,
+    setattr(logging, "VERBOSE", VERBOSE)
+    logging.addLevelName(VERBOSE, "VERBOSE")
+    setattr(logging.Logger, "verbose", lambda inst, msg, * \
+        args, **kwargs: inst.log(VERBOSE, msg, *args, **kwargs))
+    setattr(logging, "verbose", lambda msg, *args, **kwargs: logging.log(VERBOSE,
                                                                msg, *args,
-                                                               **kwargs)
+                                                               **kwargs))
 
 
 def init(args: PmbArgs):
@@ -118,11 +132,10 @@ def init(args: PmbArgs):
     add_verbose_log_level()
     root_logger.setLevel(logging.DEBUG)
     if args.verbose:
-        root_logger.setLevel(logging.VERBOSE)
+        root_logger.setLevel(VERBOSE)
 
     # Add a custom log handler
-    handler = log_handler()
-    log_handler._args = args
+    handler = log_handler(args)
     handler.setFormatter(formatter)
     root_logger.addHandler(handler)