refactor: Use PEP-526 based variable annotation (sphinx.util)

15 files changed, 54 insertions, 53 deletions

diff --git a/sphinx/util/__init__.py b/sphinx/util/__init__.py
index 83b2561f2..cb8669eca 100644
--- a/sphinx/util/__init__.py
+++ b/sphinx/util/__init__.py
@@ -47,8 +47,8 @@ if TYPE_CHECKING:
 logger = logging.getLogger(__name__)
 
 # Generally useful regular expressions.
-ws_re = re.compile(r'\s+')
-url_re = re.compile(r'(?P<schema>.+)://.*')
+ws_re: Pattern = re.compile(r'\s+')
+url_re: Pattern = re.compile(r'(?P<schema>.+)://.*')
 
 
 # High-level utility functions.
@@ -107,7 +107,7 @@ class FilenameUniqDict(dict):
     appear in.  Used for images and downloadable files in the environment.
     """
     def __init__(self) -> None:
-        self._existing = set()  # type: Set[str]
+        self._existing: Set[str] = set()
 
     def add_file(self, docname: str, newfile: str) -> str:
         if newfile in self:
@@ -379,7 +379,7 @@ def format_exception_cut_frames(x: int = 1) -> str:
     """Format an exception with traceback, but only the last x frames."""
     typ, val, tb = sys.exc_info()
     # res = ['Traceback (most recent call last):\n']
-    res = []  # type: List[str]
+    res: List[str] = []
     tbres = traceback.format_tb(tb)
     res += tbres[-x:]
     res += traceback.format_exception_only(typ, val)
diff --git a/sphinx/util/cfamily.py b/sphinx/util/cfamily.py
index 31244852c..2be2e390f 100644
--- a/sphinx/util/cfamily.py
+++ b/sphinx/util/cfamily.py
@@ -98,7 +98,7 @@ class ASTBaseBase:
             return False
         return True
 
-    __hash__ = None  # type: Callable[[], int]
+    __hash__: Callable[[], int] = None
 
     def clone(self) -> Any:
         return deepcopy(self)
@@ -223,9 +223,9 @@ class BaseParser:
 
         self.pos = 0
         self.end = len(self.definition)
-        self.last_match = None  # type: Match
-        self._previous_state = (0, None)  # type: Tuple[int, Match]
-        self.otherErrors = []  # type: List[DefinitionError]
+        self.last_match: Match = None
+        self._previous_state: Tuple[int, Match] = (0, None)
+        self.otherErrors: List[DefinitionError] = []
 
         # in our tests the following is set to False to capture bad parsing
         self.allowFallbackExpressionParsing = True
@@ -356,7 +356,7 @@ class BaseParser:
         # TODO: add handling of string literals and similar
         brackets = {'(': ')', '[': ']', '{': '}'}
         startPos = self.pos
-        symbols = []  # type: List[str]
+        symbols: List[str] = []
         while not self.eof:
             if len(symbols) == 0 and self.current_char in end:
                 break
diff --git a/sphinx/util/console.py b/sphinx/util/console.py
index 3ea5b9573..0c8008371 100644
--- a/sphinx/util/console.py
+++ b/sphinx/util/console.py
@@ -11,7 +11,7 @@
 import os
 import re
 import sys
-from typing import Dict
+from typing import Dict, Pattern
 
 try:
     # check if colorama is installed to support color on Windows
@@ -20,8 +20,8 @@ except ImportError:
     colorama = None
 
 
-_ansi_re = re.compile('\x1b\\[(\\d\\d;){0,2}\\d\\dm')
-codes = {}  # type: Dict[str, str]
+_ansi_re: Pattern = re.compile('\x1b\\[(\\d\\d;){0,2}\\d\\dm')
+codes: Dict[str, str] = {}
 
 
 def terminal_safe(s: str) -> str:
@@ -44,7 +44,7 @@ def get_terminal_width() -> int:
     return terminal_width
 
 
-_tw = get_terminal_width()
+_tw: int = get_terminal_width()
 
 
 def term_width_line(text: str) -> str:
diff --git a/sphinx/util/docfields.py b/sphinx/util/docfields.py
index 79abfe14b..43f15f507 100644
--- a/sphinx/util/docfields.py
+++ b/sphinx/util/docfields.py
@@ -27,7 +27,7 @@ def _is_single_paragraph(node: nodes.field_body) -> bool:
     if len(node) == 0:
         return False
     elif len(node) > 1:
-        for subnode in node[1:]:  # type: nodes.Node
+        for subnode in node[1:]:  # type: Node
             if not isinstance(subnode, nodes.system_message):
                 return False
     if isinstance(node[0], nodes.paragraph):
@@ -195,7 +195,7 @@ class TypedField(GroupedField):
         fieldname = nodes.field_name('', self.label)
         if len(items) == 1 and self.can_collapse:
             fieldarg, content = items[0]
-            bodynode = handle_item(fieldarg, content)  # type: nodes.Node
+            bodynode: Node = handle_item(fieldarg, content)
         else:
             bodynode = self.list_type()
             for fieldarg, content in items:
@@ -209,7 +209,7 @@ class DocFieldTransformer:
     Transforms field lists in "doc field" syntax into better-looking
     equivalents, using the field type definitions given on a domain.
     """
-    typemap = None  # type: Dict[str, Tuple[Field, bool]]
+    typemap: Dict[str, Tuple[Field, bool]] = None
 
     def __init__(self, directive: "ObjectDescription") -> None:
         self.directive = directive
@@ -227,9 +227,9 @@ class DocFieldTransformer:
         """Transform a single field list *node*."""
         typemap = self.typemap
 
-        entries = []        # type: List[Union[nodes.field, Tuple[Field, Any]]]
-        groupindices = {}   # type: Dict[str, int]
-        types = {}          # type: Dict[str, Dict]
+        entries: List[Union[nodes.field, Tuple[Field, Any]]] = []
+        groupindices: Dict[str, int] = {}
+        types: Dict[str, Dict] = {}
 
         # step 1: traverse all fields and collect field types and content
         for field in cast(List[nodes.field], node):
diff --git a/sphinx/util/docstrings.py b/sphinx/util/docstrings.py
index ac778af87..46bb5b9b8 100644
--- a/sphinx/util/docstrings.py
+++ b/sphinx/util/docstrings.py
@@ -23,7 +23,7 @@ field_list_item_re = re.compile(Body.patterns['field_marker'])
 def extract_metadata(s: str) -> Dict[str, str]:
     """Extract metadata from docstring."""
     in_other_element = False
-    metadata = {}  # type: Dict[str, str]
+    metadata: Dict[str, str] = {}
 
     if not s:
         return metadata
diff --git a/sphinx/util/docutils.py b/sphinx/util/docutils.py
index a3e49e6d7..a4ecdc647 100644
--- a/sphinx/util/docutils.py
+++ b/sphinx/util/docutils.py
@@ -42,7 +42,7 @@ if TYPE_CHECKING:
 
 
 __version_info__ = tuple(LooseVersion(docutils.__version__).version)
-additional_nodes = set()  # type: Set[Type[nodes.Element]]
+additional_nodes: Set[Type[Element]] = set()
 
 
 @contextmanager
@@ -176,8 +176,8 @@ class sphinx_domains:
     """
     def __init__(self, env: "BuildEnvironment") -> None:
         self.env = env
-        self.directive_func = None  # type: Callable
-        self.roles_func = None  # type: Callable
+        self.directive_func: Callable = None
+        self.roles_func: Callable = None
 
     def __enter__(self) -> None:
         self.enable()
@@ -491,7 +491,7 @@ class SphinxTranslator(nodes.NodeVisitor):
 
 # cache a vanilla instance of nodes.document
 # Used in new_document() function
-__document_cache__ = None  # type: nodes.document
+__document_cache__: nodes.document = None
 
 
 def new_document(source_path: str, settings: Any = None) -> nodes.document:
diff --git a/sphinx/util/inventory.py b/sphinx/util/inventory.py
index 40ac87997..f21c27323 100644
--- a/sphinx/util/inventory.py
+++ b/sphinx/util/inventory.py
@@ -93,7 +93,7 @@ class InventoryFile:
 
     @classmethod
     def load_v1(cls, stream: InventoryFileReader, uri: str, join: Callable) -> Inventory:
-        invdata = {}  # type: Inventory
+        invdata: Inventory = {}
         projname = stream.readline().rstrip()[11:]
         version = stream.readline().rstrip()[11:]
         for line in stream.readlines():
@@ -111,7 +111,7 @@ class InventoryFile:
 
     @classmethod
     def load_v2(cls, stream: InventoryFileReader, uri: str, join: Callable) -> Inventory:
-        invdata = {}  # type: Inventory
+        invdata: Inventory = {}
         projname = stream.readline().rstrip()[11:]
         version = stream.readline().rstrip()[11:]
         line = stream.readline()
diff --git a/sphinx/util/jsdump.py b/sphinx/util/jsdump.py
index 114fd7075..6d534cb3a 100644
--- a/sphinx/util/jsdump.py
+++ b/sphinx/util/jsdump.py
@@ -109,8 +109,8 @@ def loads(x: str) -> Any:
     nothing = object()
     i = 0
     n = len(x)
-    stack = []  # type: List[Union[List, Dict]]
-    obj = nothing  # type: Any
+    stack: List[Union[List, Dict]] = []
+    obj: Any = nothing
     key = False
     keys = []
     while i < n:
@@ -160,7 +160,7 @@ def loads(x: str) -> Any:
                 raise ValueError("multiple values")
             key = False
         else:
-            y = None  # type: Any
+            y: Any = None
             m = _str_re.match(x, i)
             if m:
                 y = decode_string(m.group()[1:-1])
diff --git a/sphinx/util/logging.py b/sphinx/util/logging.py
index dd04b3f23..64b7d8fb4 100644
--- a/sphinx/util/logging.py
+++ b/sphinx/util/logging.py
@@ -28,7 +28,7 @@ if TYPE_CHECKING:
 NAMESPACE = 'sphinx'
 VERBOSE = 15
 
-LEVEL_NAMES = defaultdict(lambda: logging.WARNING)  # type: Dict[str, int]
+LEVEL_NAMES: Dict[str, int] = defaultdict(lambda: logging.WARNING)
 LEVEL_NAMES.update({
     'CRITICAL': logging.CRITICAL,
     'SEVERE': logging.CRITICAL,
@@ -39,7 +39,7 @@ LEVEL_NAMES.update({
     'DEBUG': logging.DEBUG,
 })
 
-VERBOSITY_MAP = defaultdict(lambda: 0)  # type: Dict[int, int]
+VERBOSITY_MAP: Dict[int, int] = defaultdict(lambda: 0)
 VERBOSITY_MAP.update({
     0: logging.INFO,
     1: VERBOSE,
@@ -91,7 +91,7 @@ def convert_serializable(records: List[logging.LogRecord]) -> None:
 class SphinxLogRecord(logging.LogRecord):
     """Log record class supporting location"""
     prefix = ''
-    location = None  # type: Any
+    location: Any = None
 
     def getMessage(self) -> str:
         message = super().getMessage()
@@ -163,6 +163,8 @@ class NewLineStreamHandler(logging.StreamHandler):
 class MemoryHandler(logging.handlers.BufferingHandler):
     """Handler buffering all logs."""
 
+    buffer: List[logging.LogRecord]
+
     def __init__(self) -> None:
         super().__init__(-1)
 
@@ -174,7 +176,7 @@ class MemoryHandler(logging.handlers.BufferingHandler):
         try:
             for record in self.buffer:
                 logger.handle(record)
-            self.buffer = []  # type: List[logging.LogRecord]
+            self.buffer = []
         finally:
             self.release()
 
@@ -328,7 +330,7 @@ def prefixed_warnings(prefix: str) -> Generator[None, None, None]:
 
 class LogCollector:
     def __init__(self) -> None:
-        self.logs = []  # type: List[logging.LogRecord]
+        self.logs: List[logging.LogRecord] = []
 
     @contextmanager
     def collect(self) -> Generator[None, None, None]:
@@ -449,7 +451,7 @@ class OnceFilter(logging.Filter):
 
     def __init__(self, name: str = '') -> None:
         super().__init__(name)
-        self.messages = {}  # type: Dict[str, List]
+        self.messages: Dict[str, List] = {}
 
     def filter(self, record: logging.LogRecord) -> bool:
         once = getattr(record, 'once', '')
@@ -470,7 +472,7 @@ class SphinxLogRecordTranslator(logging.Filter):
     * Make a instance of SphinxLogRecord
     * docname to path if location given
     """
-    LogRecordClass = None  # type: Type[logging.LogRecord]
+    LogRecordClass: Type[logging.LogRecord] = None
 
     def __init__(self, app: "Sphinx") -> None:
         self.app = app
diff --git a/sphinx/util/matching.py b/sphinx/util/matching.py
index 2ed804677..f32d682f1 100644
--- a/sphinx/util/matching.py
+++ b/sphinx/util/matching.py
@@ -21,7 +21,7 @@ def _translate_pattern(pat: str) -> str:
     match slashes.
     """
     i, n = 0, len(pat)
-    res = ''  # type: str
+    res = ''
     while i < n:
         c = pat[i]
         i += 1
@@ -86,7 +86,7 @@ class Matcher:
 DOTFILES = Matcher(['**/.*'])
 
 
-_pat_cache = {}  # type: Dict[str, Pattern]
+_pat_cache: Dict[str, Pattern] = {}
 
 
 def patmatch(name: str, pat: str) -> Optional[Match[str]]:
diff --git a/sphinx/util/nodes.py b/sphinx/util/nodes.py
index c7619a836..61d688d8e 100644
--- a/sphinx/util/nodes.py
+++ b/sphinx/util/nodes.py
@@ -251,7 +251,7 @@ META_TYPE_NODES = (
 
 def extract_messages(doctree: Element) -> Iterable[Tuple[Element, str]]:
     """Extract translatable messages from a document tree."""
-    for node in doctree.traverse(is_translatable):  # type: nodes.Element
+    for node in doctree.traverse(is_translatable):  # type: Element
         if isinstance(node, addnodes.translatable):
             for msg in node.extract_original_messages():
                 yield node, msg
@@ -363,7 +363,7 @@ indextypes = [
 def process_index_entry(entry: str, targetid: str) -> List[Tuple[str, str, str, str, str]]:
     from sphinx.domains.python import pairindextypes
 
-    indexentries = []  # type: List[Tuple[str, str, str, str, str]]
+    indexentries: List[Tuple[str, str, str, str, str]] = []
     entry = entry.strip()
     oentry = entry
     main = ''
diff --git a/sphinx/util/osutil.py b/sphinx/util/osutil.py
index 5ee2eccc8..c8ecce9e2 100644
--- a/sphinx/util/osutil.py
+++ b/sphinx/util/osutil.py
@@ -185,7 +185,7 @@ class FileAvoidWrite:
     """
     def __init__(self, path: str) -> None:
         self._path = path
-        self._io = None  # type: Optional[StringIO]
+        self._io: Optional[StringIO] = None
 
     def write(self, data: str) -> None:
         if not self._io:
diff --git a/sphinx/util/parallel.py b/sphinx/util/parallel.py
index ed73ee4d6..7ad7f81e7 100644
--- a/sphinx/util/parallel.py
+++ b/sphinx/util/parallel.py
@@ -60,15 +60,15 @@ class ParallelTasks:
     def __init__(self, nproc: int) -> None:
         self.nproc = nproc
         # (optional) function performed by each task on the result of main task
-        self._result_funcs = {}  # type: Dict[int, Callable]
+        self._result_funcs: Dict[int, Callable] = {}
         # task arguments
-        self._args = {}  # type: Dict[int, List[Any]]
+        self._args: Dict[int, List[Any]] = {}
         # list of subprocesses (both started and waiting)
-        self._procs = {}  # type: Dict[int, multiprocessing.Process]
+        self._procs: Dict[int, multiprocessing.Process] = {}
         # list of receiving pipe connections of running subprocesses
-        self._precvs = {}  # type: Dict[int, Any]
+        self._precvs: Dict[int, Any] = {}
         # list of receiving pipe connections of waiting subprocesses
-        self._precvsWaiting = {}  # type: Dict[int, Any]
+        self._precvsWaiting: Dict[int, Any] = {}
         # number of working subprocesses
         self._pworking = 0
         # task number of each subprocess
diff --git a/sphinx/util/rst.py b/sphinx/util/rst.py
index 79ede3432..82b3f6bda 100644
--- a/sphinx/util/rst.py
+++ b/sphinx/util/rst.py
@@ -30,8 +30,7 @@ symbols_re = re.compile(r'([!-\-/:-@\[-`{-~])')  # symbols without dot(0x2e)
 SECTIONING_CHARS = ['=', '-', '~']
 
 # width of characters
-WIDECHARS = defaultdict(lambda: "WF")   # type: Dict[str, str]
-                                        # WF: Wide + Full-width
+WIDECHARS: Dict[str, str] = defaultdict(lambda: "WF")  # WF: Wide + Full-width
 WIDECHARS["ja"] = "WFA"  # In Japanese, Ambiguous characters also have double width
 
 
diff --git a/sphinx/util/texescape.py b/sphinx/util/texescape.py
index 7323d2c27..417a963a7 100644
--- a/sphinx/util/texescape.py
+++ b/sphinx/util/texescape.py
@@ -98,12 +98,12 @@ unicode_tex_replacements = [
 # %, {, }, \, #, and ~ are the only ones which must be replaced by _ character
 # It would be simpler to define it entirely here rather than in init().
 # Unicode replacements are superfluous, as idescape() uses backslashreplace
-tex_replace_map = {}  # type: Dict[int, str]
+tex_replace_map: Dict[int, str] = {}
 
-_tex_escape_map = {}  # type: Dict[int, str]
-_tex_escape_map_without_unicode = {}  # type: Dict[int, str]
-_tex_hlescape_map = {}  # type: Dict[int, str]
-_tex_hlescape_map_without_unicode = {}  # type: Dict[int, str]
+_tex_escape_map: Dict[int, str] = {}
+_tex_escape_map_without_unicode: Dict[int, str] = {}
+_tex_hlescape_map: Dict[int, str] = {}
+_tex_hlescape_map_without_unicode: Dict[int, str] = {}
 
 
 def escape(s: str, latex_engine: str = None) -> str: