1 files changed, 14 insertions, 13 deletions

diff --git a/sphinx/util/logging.py b/sphinx/util/logging.py
index 09780723a..64b7d8fb4 100644
--- a/sphinx/util/logging.py
+++ b/sphinx/util/logging.py
@@ -12,7 +12,7 @@ import logging
 import logging.handlers
 from collections import defaultdict
 from contextlib import contextmanager
-from typing import IO, Any, Dict, Generator, List, Tuple, Union
+from typing import IO, TYPE_CHECKING, Any, Dict, Generator, List, Optional, Tuple, Type, Union
 
 from docutils import nodes
 from docutils.nodes import Node
@@ -21,17 +21,14 @@ from docutils.utils import get_source_line
 from sphinx.errors import SphinxWarning
 from sphinx.util.console import colorize
 
-if False:
-    # For type annotation
-    from typing import Type  # for python3.5.1
-
+if TYPE_CHECKING:
     from sphinx.application import Sphinx
 
 
 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,
@@ -42,7 +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,
@@ -94,7 +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()
@@ -166,6 +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)
 
@@ -177,7 +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()
 
@@ -331,7 +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]:
@@ -356,6 +355,8 @@ def is_suppressed_warning(type: str, subtype: str, suppress_warnings: List[str])
     if type is None:
         return False
 
+    subtarget: Optional[str]
+
     for warning_type in suppress_warnings:
         if '.' in warning_type:
             target, subtarget = warning_type.split('.', 1)
@@ -450,7 +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', '')
@@ -471,7 +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
@@ -509,7 +510,7 @@ class WarningLogRecordTranslator(SphinxLogRecordTranslator):
     LogRecordClass = SphinxWarningLogRecord
 
 
-def get_node_location(node: Node) -> str:
+def get_node_location(node: Node) -> Optional[str]:
     (source, line) = get_source_line(node)
     if source and line:
         return "%s:%s" % (source, line)