cpp-linter · 2bndy5 · Feb 6, 2026 · Feb 6, 2026 · Feb 6, 2026 · Feb 6, 2026
diff --git a/cpp_linter/clang_tools/__init__.py b/cpp_linter/clang_tools/__init__.py
@@ -3,7 +3,7 @@
 from pathlib import Path
 import re
 import subprocess
-from typing import Optional, List, Dict, Tuple, cast
+from typing import cast
 import shutil
 
 from ..common_fs import FileObj, FileIOTimeout
@@ -14,7 +14,7 @@
 from ..cli import Args
 
 
-def assemble_version_exec(tool_name: str, specified_version: str) -> Optional[str]:
+def assemble_version_exec(tool_name: str, specified_version: str) -> str | None:
     """Assembles the command to the executable of the given clang tool based on given
     version information.
 
@@ -37,13 +37,13 @@ def assemble_version_exec(tool_name: str, specified_version: str) -> Optional[st
 def _run_on_single_file(
     file: FileObj,
     log_lvl: int,
-    tidy_cmd: Optional[str],
-    db_json: Optional[List[Dict[str, str]]],
-    format_cmd: Optional[str],
-    format_filter: Optional[FormatFileFilter],
-    tidy_filter: Optional[TidyFileFilter],
+    tidy_cmd: str | None,
+    db_json: list[dict[str, str]] | None,
+    format_cmd: str | None,
+    format_filter: FormatFileFilter | None,
+    tidy_filter: TidyFileFilter | None,
     args: Args,
-) -> Tuple[str, str, Optional[TidyAdvice], Optional[FormatAdvice]]:
+) -> tuple[str, str, TidyAdvice | None, FormatAdvice | None]:
     log_stream = worker_log_init(log_lvl)
     filename = Path(file.name).as_posix()
 
@@ -115,11 +115,11 @@ def _capture_tool_version(cmd: str) -> str:
 
 class ClangVersions:
     def __init__(self) -> None:
-        self.tidy: Optional[str] = None
-        self.format: Optional[str] = None
+        self.tidy: str | None = None
+        self.format: str | None = None
 
 
-def capture_clang_tools_output(files: List[FileObj], args: Args) -> ClangVersions:
+def capture_clang_tools_output(files: list[FileObj], args: Args) -> ClangVersions:
     """Execute and capture all output from clang-tidy and clang-format. This aggregates
     results in the :attr:`~cpp_linter.Globals.OUTPUT`.
 
@@ -150,7 +150,7 @@ def capture_clang_tools_output(files: List[FileObj], args: Args) -> ClangVersion
             ignore_value=args.ignore_tidy,
         )
 
-    db_json: Optional[List[Dict[str, str]]] = None
+    db_json: list[dict[str, str]] | None = None
     if args.database:
         db = Path(args.database)
         if not db.is_absolute():

diff --git a/cpp_linter/clang_tools/clang_format.py b/cpp_linter/clang_tools/clang_format.py
@@ -2,7 +2,7 @@
 
 from pathlib import PurePath
 import subprocess
-from typing import List, cast
+from typing import cast
 
 import xml.etree.ElementTree as ET
 
@@ -45,7 +45,7 @@ def __init__(self, line_numb: int):
         self.line = line_numb
 
         #: A list of `FormatReplacement` object(s) representing suggestions.
-        self.replacements: List[FormatReplacement] = []
+        self.replacements: list[FormatReplacement] = []
 
     def __repr__(self):
         return (
@@ -66,7 +66,7 @@ def __init__(self, filename: str):
         #: The source file that the suggestion concerns.
         self.filename = PurePath(filename).as_posix()
 
-        self.replaced_lines: List[FormatReplacementLine] = []
+        self.replaced_lines: list[FormatReplacementLine] = []
         """A list of `FormatReplacementLine` representing replacement(s)
         on a single line."""
 
@@ -85,7 +85,7 @@ def get_tool_name(self) -> str:
         return "clang-format"
 
 
-def tally_format_advice(files: List[FileObj]) -> int:
+def tally_format_advice(files: list[FileObj]) -> int:
     """Returns the sum of clang-format errors"""
     format_checks_failed = 0
     for file_obj in files:
@@ -126,7 +126,7 @@ def parse_format_replacements_xml(
     if not xml_out:
         return format_advice
     ranges = cast(
-        List[List[int]],
+        list[list[int]],
         file_obj.range_of_changed_lines(lines_changed_only, get_ranges=True),
     )
     tree = ET.fromstring(xml_out)
@@ -183,7 +183,7 @@ def run_clang_format(
         "--output-replacements-xml",
     ]
     ranges = cast(
-        List[List[int]],
+        list[list[int]],
         file_obj.range_of_changed_lines(lines_changed_only, get_ranges=True),
     )
     for span in ranges:

diff --git a/cpp_linter/clang_tools/clang_tidy.py b/cpp_linter/clang_tools/clang_tidy.py
@@ -5,7 +5,7 @@
 from pathlib import Path, PurePath
 import re
 import subprocess
-from typing import Tuple, Union, List, cast, Optional, Dict, Set
+from typing import cast
 from ..loggers import logger
 from ..common_fs import FileObj
 from .patcher import PatchMixin, ReviewComments, Suggestion
@@ -30,8 +30,8 @@ class TidyNotification:
 
     def __init__(
         self,
-        notification_line: Tuple[str, Union[int, str], Union[int, str], str, str, str],
-        database: Optional[List[Dict[str, str]]] = None,
+        notification_line: tuple[str, int | str, int | str, str, str, str],
+        database: list[dict[str, str]] | None = None,
     ):
         # logger.debug("Creating tidy note from line %s", notification_line)
         (
@@ -78,9 +78,9 @@ def __init__(
         #: The source filename concerning the notification.
         self.filename = rel_path
         #: A `list` of lines for the code-block in the notification.
-        self.fixit_lines: List[str] = []
+        self.fixit_lines: list[str] = []
         #: A list of line numbers where a suggested fix was applied.
-        self.applied_fixes: Set[int] = set()
+        self.applied_fixes: set[int] = set()
 
     @property
     def diagnostic_link(self) -> str:
@@ -105,7 +105,7 @@ def __repr__(self) -> str:
 
 
 class TidyAdvice(PatchMixin):
-    def __init__(self, notes: List[TidyNotification]) -> None:
+    def __init__(self, notes: list[TidyNotification]) -> None:
         #: A buffer of the applied fixes from clang-tidy
         super().__init__()
         self.notes = notes
@@ -174,7 +174,7 @@ def _has_related_suggestion(suggestion: Suggestion) -> bool:
                         review_comments.suggestions.append(suggestion)
 
 
-def tally_tidy_advice(files: List[FileObj]) -> int:
+def tally_tidy_advice(files: list[FileObj]) -> int:
     """Returns the sum of clang-format errors"""
     tidy_checks_failed = 0
     for file_obj in files:
@@ -194,8 +194,8 @@ def run_clang_tidy(
     checks: str,
     lines_changed_only: int,
     database: str,
-    extra_args: List[str],
-    db_json: Optional[List[Dict[str, str]]],
+    extra_args: list[str],
+    db_json: list[dict[str, str]] | None,
     tidy_review: bool,
     style: str,
 ) -> TidyAdvice:
@@ -277,7 +277,7 @@ def run_clang_tidy(
 
 
 def parse_tidy_output(
-    tidy_out: str, database: Optional[List[Dict[str, str]]]
+    tidy_out: str, database: list[dict[str, str]] | None
 ) -> TidyAdvice:
     """Parse clang-tidy stdout.
 
@@ -300,7 +300,7 @@ def parse_tidy_output(
             if " " not in diagnostic_name and "-" in diagnostic_name:
                 notification = TidyNotification(
                     cast(
-                        Tuple[str, Union[int, str], Union[int, str], str, str, str],
+                        tuple[str, int | str, int | str, str, str, str],
                         note_match.groups(),
                     ),
                     database,

diff --git a/cpp_linter/clang_tools/patcher.py b/cpp_linter/clang_tools/patcher.py
@@ -2,7 +2,7 @@
 by the clang tool's output."""
 
 from abc import ABC
-from typing import Optional, Dict, Any, List, Tuple
+from typing import Any
 from pygit2 import Patch  # type: ignore
 from ..common_fs import FileObj
 from pygit2.enums import DiffOption  # type: ignore
@@ -27,7 +27,7 @@ def __init__(self, file_name: str) -> None:
         #: The markdown comment about the suggestion.
         self.comment: str = ""
 
-    def serialize_to_github_payload(self) -> Dict[str, Any]:
+    def serialize_to_github_payload(self) -> dict[str, Any]:
         """Serialize this object into a JSON compatible with Github's REST API."""
         assert self.line_end > 0, "ending line number unknown"
         from ..rest_api import COMMENT_MARKER  # workaround circular import
@@ -47,9 +47,9 @@ class ReviewComments:
 
     def __init__(self) -> None:
         #: The list of actual comments
-        self.suggestions: List[Suggestion] = []
+        self.suggestions: list[Suggestion] = []
 
-        self.tool_total: Dict[str, Optional[int]] = {
+        self.tool_total: dict[str, int | None] = {
             "clang-tidy": None,
             "clang-format": None,
         }
@@ -62,7 +62,7 @@ def __init__(self) -> None:
         A `None` value means a review was not requested from the corresponding tool.
         """
 
-        self.full_patch: Dict[str, str] = {"clang-tidy": "", "clang-format": ""}
+        self.full_patch: dict[str, str] = {"clang-tidy": "", "clang-format": ""}
         """The full patch of all the suggestions (including those that will not
         fit within the diff)"""
 
@@ -84,9 +84,9 @@ def merge_similar_suggestion(self, suggestion: Suggestion) -> bool:
     def serialize_to_github_payload(
         # avoid circular imports by accepting primitive types (instead of ClangVersions)
         self,
-        tidy_version: Optional[str],
-        format_version: Optional[str],
-    ) -> Tuple[str, List[Dict[str, Any]]]:
+        tidy_version: str | None,
+        format_version: str | None,
+    ) -> tuple[str, list[dict[str, Any]]]:
         """Serialize this object into a summary and list of comments compatible
         with Github's REST API.
 
@@ -143,7 +143,7 @@ class PatchMixin(ABC):
 
     def __init__(self) -> None:
         #: A unified diff of the applied fixes from the clang tool's output
-        self.patched: Optional[bytes] = None
+        self.patched: bytes | None = None
 
     def get_suggestion_help(self, start, end) -> str:
         """Create helpful text about what the suggestion aims to fix.

diff --git a/cpp_linter/cli.py b/cpp_linter/cli.py
@@ -2,7 +2,7 @@
 
 import argparse
 from collections import UserDict
-from typing import Optional, List, Dict, Any, Sequence, Union
+from typing import Any, Sequence
 
 
 class Args(UserDict):
@@ -14,7 +14,7 @@ class Args(UserDict):
     #: See :std:option:`--database`.
     database: str = ""
     #: See :std:option:`--diff-base`.
-    diff_base: Optional[Union[int, str]] = None
+    diff_base: int | str | None = None
     #: See :std:option:`--ignore-index`.
     ignore_index: bool = False
     #: See :std:option:`--style`.
@@ -27,7 +27,7 @@ class Args(UserDict):
     #: See :std:option:`--version`.
     version: str = ""
     #: See :std:option:`--extensions`.
-    extensions: List[str] = [
+    extensions: list[str] = [
         "c",
         "h",
         "C",
@@ -56,28 +56,28 @@ class Args(UserDict):
     #: See :std:option:`--file-annotations`.
     file_annotations: bool = True
     #: See :std:option:`--extra-arg`.
-    extra_arg: List[str] = []
+    extra_arg: list[str] = []
     #: See :std:option:`--no-lgtm`.
     no_lgtm: bool = True
     #: See :std:option:`files`.
-    files: List[str] = []
+    files: list[str] = []
     #: See :std:option:`--tidy-review`.
     tidy_review: bool = False
     #: See :std:option:`--format-review`.
     format_review: bool = False
     #: See :std:option:`--jobs`.
-    jobs: Optional[int] = 1
+    jobs: int | None = 1
     #: See :std:option:`--ignore-tidy`.
     ignore_tidy: str = ""
     #: See :std:option:`--ignore-format`.
     ignore_format: str = ""
     #: See :std:option:`--passive-reviews`.
     passive_reviews: bool = False
     #: A subcommand if provided
-    command: Optional[str] = None
+    command: str | None = None
 
 
-_parser_args: Dict[Sequence[str], Any] = {}
+_parser_args: dict[Sequence[str], Any] = {}
 _parser_args[("-v", "--verbosity")] = dict(
     type=lambda a: a.lower() in ["debug", "10"],
     default="info",
@@ -388,7 +388,7 @@ class Args(UserDict):
 )
 
 
-def _parse_jobs(val: str) -> Optional[int]:
+def _parse_jobs(val: str) -> int | None:
     try:
         jobs = int(val)
     except ValueError as exc: