Fix most blib2to3 lint (#3794)

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 # Note: don't use this config for your own repositories. Instead, see
 # "Version control integration" in docs/integrations/source_version_control.md
-exclude: ^(src/blib2to3/|profiling/|tests/data/)
+exclude: ^(profiling/|tests/data/)
 repos:
   - repo: local
     hooks:
@@ -36,6 +36,7 @@ repos:
           - flake8-bugbear
           - flake8-comprehensions
           - flake8-simplify
+        exclude: ^src/blib2to3/
 
   - repo: https://github.com/pre-commit/mirrors-mypy
     rev: v1.4.1

pyproject.toml

@@ -12,8 +12,7 @@ include = '\.pyi?$'
 extend-exclude = '''
 /(
   # The following are specific to Black, you probably don't want those.
-  | blib2to3
-  | tests/data
+  tests/data
   | profiling
 )/
 '''
@@ -183,7 +182,7 @@ atomic = true
 profile = "black"
 line_length = 88
 skip_gitignore = true
-skip_glob = ["src/blib2to3", "tests/data", "profiling"]
+skip_glob = ["tests/data", "profiling"]
 known_first_party = ["black", "blib2to3", "blackd", "_black_version"]
 
 [tool.pytest.ini_options]

src/blib2to3/README

@@ -1,18 +1,19 @@
-A subset of lib2to3 taken from Python 3.7.0b2.
-Commit hash: 9c17e3a1987004b8bcfbe423953aad84493a7984
+A subset of lib2to3 taken from Python 3.7.0b2. Commit hash:
+9c17e3a1987004b8bcfbe423953aad84493a7984
 
 Reasons for forking:
+
 - consistent handling of f-strings for users of Python < 3.6.2
-- backport of BPO-33064 that fixes parsing files with trailing commas after
-  *args and **kwargs
-- backport of GH-6143 that restores the ability to reformat legacy usage of
-  `async`
+- backport of BPO-33064 that fixes parsing files with trailing commas after \*args and
+  \*\*kwargs
+- backport of GH-6143 that restores the ability to reformat legacy usage of `async`
 - support all types of string literals
 - better ability to debug (better reprs)
 - INDENT and DEDENT don't hold whitespace and comment prefixes
 - ability to Cythonize
 
 Change Log:
+
 - Changes default logger used by Driver
 - Backported the following upstream parser changes:
   - "bpo-42381: Allow walrus in set literals and set comprehensions (GH-23332)"

src/blib2to3/pgen2/driver.py

@@ -17,30 +17,21 @@
 
 # Python imports
 import io
-import os
 import logging
+import os
 import pkgutil
 import sys
-from typing import (
-    Any,
-    cast,
-    IO,
-    Iterable,
-    List,
-    Optional,
-    Iterator,
-    Tuple,
-    Union,
-)
 from contextlib import contextmanager
 from dataclasses import dataclass, field
-
-# Pgen imports
-from . import grammar, parse, token, tokenize, pgen
 from logging import Logger
-from blib2to3.pytree import NL
+from typing import IO, Any, Iterable, Iterator, List, Optional, Tuple, Union, cast
+
 from blib2to3.pgen2.grammar import Grammar
 from blib2to3.pgen2.tokenize import GoodTokenInfo
+from blib2to3.pytree import NL
+
+# Pgen imports
+from . import grammar, parse, pgen, token, tokenize
 
 Path = Union[str, "os.PathLike[str]"]
 

src/blib2to3/pgen2/literals.py

@@ -4,10 +4,8 @@
 """Safely evaluate Python string literals without using eval()."""
 
 import re
-
 from typing import Dict, Match
 
-
 simple_escapes: Dict[str, str] = {
     "a": "\a",
     "b": "\b",

src/blib2to3/pgen2/parse.py

@@ -10,24 +10,25 @@
 
 """
 from contextlib import contextmanager
+from typing import (
+    TYPE_CHECKING,
+    Any,
+    Callable,
+    Dict,
+    Iterator,
+    List,
+    Optional,
+    Set,
+    Tuple,
+    Union,
+    cast,
+)
+
+from blib2to3.pgen2.grammar import Grammar
+from blib2to3.pytree import NL, Context, Leaf, Node, RawNode, convert
 
 # Local imports
 from . import grammar, token, tokenize
-from typing import (
-    cast,
-    Any,
-    Optional,
-    Union,
-    Tuple,
-    Dict,
-    List,
-    Iterator,
-    Callable,
-    Set,
-    TYPE_CHECKING,
-)
-from blib2to3.pgen2.grammar import Grammar
-from blib2to3.pytree import convert, NL, Context, RawNode, Leaf, Node
 
 if TYPE_CHECKING:
     from blib2to3.pgen2.driver import TokenProxy
@@ -112,7 +113,9 @@ def add_token(self, tok_type: int, tok_val: str, raw: bool = False) -> None:
                     args.insert(0, ilabel)
                 func(*args)
 
-    def determine_route(self, value: Optional[str] = None, force: bool = False) -> Optional[int]:
+    def determine_route(
+        self, value: Optional[str] = None, force: bool = False
+    ) -> Optional[int]:
         alive_ilabels = self.ilabels
         if len(alive_ilabels) == 0:
             *_, most_successful_ilabel = self._dead_ilabels

src/blib2to3/pgen2/pgen.py

@@ -1,25 +1,22 @@
 # Copyright 2004-2005 Elemental Security, Inc. All Rights Reserved.
 # Licensed to PSF under a Contributor Agreement.
 
-# Pgen imports
-from . import grammar, token, tokenize
-
+import os
 from typing import (
+    IO,
     Any,
     Dict,
-    IO,
     Iterator,
     List,
+    NoReturn,
     Optional,
+    Sequence,
     Tuple,
     Union,
-    Sequence,
-    NoReturn,
 )
-from blib2to3.pgen2 import grammar
-from blib2to3.pgen2.tokenize import GoodTokenInfo
-import os
 
+from blib2to3.pgen2 import grammar, token, tokenize
+from blib2to3.pgen2.tokenize import GoodTokenInfo
 
 Path = Union[str, "os.PathLike[str]"]
 
@@ -149,7 +146,7 @@ def calcfirst(self, name: str) -> None:
         state = dfa[0]
         totalset: Dict[str, int] = {}
         overlapcheck = {}
-        for label, next in state.arcs.items():
+        for label in state.arcs:
             if label in self.dfas:
                 if label in self.first:
                     fset = self.first[label]
@@ -190,9 +187,9 @@ def parse(self) -> Tuple[Dict[str, List["DFAState"]], str]:
             # self.dump_nfa(name, a, z)
             dfa = self.make_dfa(a, z)
             # self.dump_dfa(name, dfa)
-            oldlen = len(dfa)
+            # oldlen = len(dfa)
             self.simplify_dfa(dfa)
-            newlen = len(dfa)
+            # newlen = len(dfa)
             dfas[name] = dfa
             # print name, oldlen, newlen
             if startsymbol is None:
@@ -346,7 +343,7 @@ def parse_atom(self) -> Tuple["NFAState", "NFAState"]:
             self.raise_error(
                 "expected (...) or NAME or STRING, got %s/%s", self.type, self.value
             )
-            assert False
+            raise AssertionError
 
     def expect(self, type: int, value: Optional[Any] = None) -> str:
         if self.type != type or (value is not None and self.value != value):
@@ -368,7 +365,7 @@ def raise_error(self, msg: str, *args: Any) -> NoReturn:
         if args:
             try:
                 msg = msg % args
-            except:
+            except Exception:
                 msg = " ".join([msg] + list(map(str, args)))
         raise SyntaxError(msg, (self.filename, self.end[0], self.end[1], self.line))
 

src/blib2to3/pgen2/token.py

@@ -1,8 +1,6 @@
 """Token constants (from "token.h")."""
 
-from typing import Dict
-
-from typing import Final
+from typing import Dict, Final
 
 #  Taken from Python (r53757) and modified to include some tokens
 #   originally monkeypatched in by pgen2.tokenize

src/blib2to3/pgen2/tokenize.py

@@ -30,28 +30,41 @@
 import sys
 from typing import (
     Callable,
+    Final,
     Iterable,
     Iterator,
     List,
     Optional,
+    Pattern,
     Set,
     Tuple,
-    Pattern,
     Union,
     cast,
 )
 
-from typing import Final
-
-from blib2to3.pgen2.token import *
 from blib2to3.pgen2.grammar import Grammar
+from blib2to3.pgen2.token import (
+    ASYNC,
+    AWAIT,
+    COMMENT,
+    DEDENT,
+    ENDMARKER,
+    ERRORTOKEN,
+    INDENT,
+    NAME,
+    NEWLINE,
+    NL,
+    NUMBER,
+    OP,
+    STRING,
+    tok_name,
+)
 
 __author__ = "Ka-Ping Yee <ping@lfw.org>"
 __credits__ = "GvR, ESR, Tim Peters, Thomas Wouters, Fred Drake, Skip Montanaro"
 
 import re
 from codecs import BOM_UTF8, lookup
-from blib2to3.pgen2.token import *
 
 from . import token
 
@@ -334,7 +347,7 @@ def read_or_stop() -> bytes:
         try:
             return readline()
         except StopIteration:
-            return b''
+            return b""
 
     def find_cookie(line: bytes) -> Optional[str]:
         try:
@@ -676,14 +689,12 @@ def generate_tokens(
         yield stashed
         stashed = None
 
-    for indent in indents[1:]:  # pop remaining indent levels
+    for _indent in indents[1:]:  # pop remaining indent levels
         yield (DEDENT, "", (lnum, 0), (lnum, 0), "")
     yield (ENDMARKER, "", (lnum, 0), (lnum, 0), "")
 
 
 if __name__ == "__main__":  # testing
-    import sys
-
     if len(sys.argv) > 1:
         tokenize(open(sys.argv[1]).readline)
     else:

src/blib2to3/pygram.py

@@ -5,12 +5,10 @@
 
 # Python imports
 import os
-
 from typing import Union
 
 # Local imports
 from .pgen2 import driver
-
 from .pgen2.grammar import Grammar
 
 # Moved into initialize because mypyc can't handle __file__ (XXX bug)

src/blib2to3/pytree.py

@@ -15,15 +15,16 @@
 from typing import (
     Any,
     Dict,
+    Iterable,
     Iterator,
     List,
     Optional,
+    Set,
     Tuple,
     TypeVar,
     Union,
-    Set,
-    Iterable,
 )
+
 from blib2to3.pgen2.grammar import Grammar
 
 __author__ = "Guido van Rossum <guido@python.org>"
@@ -58,7 +59,6 @@ def type_repr(type_num: int) -> Union[str, int]:
 
 
 class Base:
-
     """
     Abstract base class for Node and Leaf.
 
@@ -237,7 +237,6 @@ def get_suffix(self) -> str:
 
 
 class Node(Base):
-
     """Concrete implementation for interior nodes."""
 
     fixers_applied: Optional[List[Any]]
@@ -378,7 +377,6 @@ def update_sibling_maps(self) -> None:
 
 
 class Leaf(Base):
-
     """Concrete implementation for leaf nodes."""
 
     # Default values for instance variables
@@ -506,7 +504,6 @@ def convert(gr: Grammar, raw_node: RawNode) -> NL:
 
 
 class BasePattern:
-
     """
     A pattern is a tree matching pattern.
 
@@ -646,7 +643,6 @@ def _submatch(self, node, results=None):
 
 
 class NodePattern(BasePattern):
-
     wildcards: bool = False
 
     def __init__(
@@ -715,7 +711,6 @@ def _submatch(self, node, results=None) -> bool:
 
 
 class WildcardPattern(BasePattern):
-
     """
     A wildcard pattern can match zero or more nodes.