Improve typing

.gitignore

@@ -92,5 +92,5 @@ ENV/
 /.settings
 .vscode
 
-# pyright
-pyrightconfig.json
+# Pyright
+pyrightconfig.json

beets/plugins.py

@@ -21,6 +21,7 @@
 import traceback
 from collections import defaultdict
 from functools import wraps
+from typing import Any, Dict
 
 import mediafile
 
@@ -291,7 +292,7 @@ def load_plugins(names=()):
             )
 
 
-_instances = {}
+_instances: Dict[Any, Any] = {}
 
 
 def find_plugins():

beets/util/__init__.py

@@ -168,7 +168,7 @@
     """Provide the canonical form of the path suitable for storing in
     the database.
     """
     path = syspath(path, prefix=False)
     path = os.path.normpath(os.path.abspath(os.path.expanduser(path)))
     return bytestring_path(path)
 
@@ -182,7 +182,7 @@
 
     The argument should *not* be the result of a call to `syspath`.
     """
     out = []
     last_path = None
     while path:
         path = os.path.dirname(path)
@@ -199,17 +199,17 @@
 
 def sorted_walk(
     path: AnyStr,
     ignore: Sequence = (),
     ignore_hidden: bool = False,
     logger: Optional[Logger] = None,
 ) -> Generator[Tuple, None, None]:
     """Like `os.walk`, but yields things in case-insensitive sorted,
     breadth-first order.  Directory and file names matching any glob
     pattern in `ignore` are skipped. If `logger` is provided, then
     warning messages are logged there when a directory cannot be listed.
     """
     # Make sure the paths aren't Unicode strings.
     path = bytestring_path(path)
     ignore = [bytestring_path(i) for i in ignore]
 
     # Get all the directories and files at this level.
@@ -226,7 +226,7 @@
     dirs = []
     files = []
     for base in contents:
         base = bytestring_path(base)
 
         # Skip ignored filenames.
         skip = False
@@ -242,16 +242,16 @@
             continue
 
         # Add to output as either a file or a directory.
         cur = os.path.join(path, base)
         if (ignore_hidden and not hidden.is_hidden(cur)) or not ignore_hidden:
             if os.path.isdir(syspath(cur)):
                 dirs.append(base)
             else:
                 files.append(base)
 
     # Sort lists (case-insensitive) and yield the current level.
     dirs.sort(key=bytes.lower)
     files.sort(key=bytes.lower)
     yield (path, dirs, files)
 
     # Recurse into directories.
@@ -300,7 +300,7 @@
 def prune_dirs(
     path: str,
     root: Optional[Bytes_or_String] = None,
-    clutter: Sequence[str] = (".DS_Store", "Thumbs.db"),
+    clutter: Sequence[Bytes_or_String] = [".DS_Store", "Thumbs.db"],
 ):
     """If path is an empty directory, then remove it. Recursively remove
     path's ancestry up to root (which is never removed) where there are
@@ -332,7 +332,7 @@
         if not os.path.exists(directory):
             # Directory gone already.
             continue
-        clutter: List[bytes] = [bytestring_path(c) for c in clutter]
+        clutter = [bytestring_path(c) for c in clutter]
         match_paths = [bytestring_path(d) for d in os.listdir(directory)]
         try:
             if fnmatch_all(match_paths, clutter):
@@ -441,14 +441,18 @@
         return path.decode("utf-8", "ignore")
 
 
-def syspath(path: PathLike, prefix: bool = True) -> str:
+def syspath(path: Optional[PathLike], prefix: bool = True) -> str:
     """Convert a path for use by the operating system. In particular,
     paths on Windows must receive a magic prefix and must be converted
     to Unicode before they are sent to the OS. To disable the magic
     prefix on Windows, set `prefix` to False---but only do this if you
     *really* know what you're doing.
     """
+    if path is None:
+        raise ValueError("The path cannot be None")
+
     str_path = os.fsdecode(path)
+
     # Don't do anything if we're not on windows
     if os.path.__name__ != "ntpath":
         return str_path
@@ -760,7 +764,7 @@
     length: int,
     extension: bytes,
     fragment: bool,
-) -> Tuple[Union[Bytes_or_String, bool]]:
+) -> Tuple[Bytes_or_String, bool]:
     """Given a path-like Unicode string, produce a legal path. Return
     the path and a flag indicating whether some replacements had to be
     ignored (see below).
@@ -827,7 +831,7 @@
         return str(value)
 
 
-def plurality(objs: Sequence[T]) -> T:
+def plurality(objs: Sequence[T]) -> Tuple[T, int]:
     """Given a sequence of hashble objects, returns the object that
     is most common in the set and the its number of appearance. The
     sequence must contain at least one object.
@@ -838,7 +842,7 @@
     return c.most_common(1)[0]
 
 
-def convert_command_args(args: List[bytes]) -> List[str]:
+def convert_command_args(args: Sequence[Bytes_or_String]) -> List[str]:
     """Convert command arguments, which may either be `bytes` or `str`
     objects, to uniformly surrogate-escaped strings."""
     assert isinstance(args, list)
@@ -858,7 +862,7 @@
 
 
 def command_output(
-    cmd: List[Bytes_or_String],
+    cmd: Sequence[Bytes_or_String],
     shell: bool = False,
 ) -> CommandOutput:
     """Runs the command and returns its output after it has exited.
@@ -1040,7 +1044,7 @@
     # if this platform has an os.altsep, change it to os.sep.
     if os.altsep:
         path = path.replace(os.altsep, os.sep)
-    path_components: List[Bytes_or_String] = path.split(os.sep)
+    path_components: Sequence[Bytes_or_String] = path.split(os.sep)
     for index, item in enumerate(path_components):
         path_components[index] = unidecode(item).replace(os.sep, sep_replace)
         if os.altsep: