Improve performance by skipping unnecessary normalisation (#3751)

[etc/vim.git] / src / blib2to3 / pgen2 / tokenize.py

diff --git a/src/blib2to3/pgen2/tokenize.py b/src/blib2to3/pgen2/tokenize.py
index 2d0cc4324ce75b7554500c96c1aea7ce69ea923b..1dea89d7bb89c97914bbe0d21b82ffc113418296 100644 (file)
--- a/src/blib2to3/pgen2/tokenize.py
+++ b/src/blib2to3/pgen2/tokenize.py
@@ -35,17 +35,13 @@ from typing import (
     List,
     Optional,
     Set,
-    Text,
     Tuple,
     Pattern,
     Union,
     cast,
 )
 
-if sys.version_info >= (3, 8):
-    from typing import Final
-else:
-    from typing_extensions import Final
+from typing import Final
 
 from blib2to3.pgen2.token import *
 from blib2to3.pgen2.grammar import Grammar
@@ -80,7 +76,7 @@ def maybe(*choices: str) -> str:
 
 
 def _combinations(*l: str) -> Set[str]:
-    return set(x + y for x in l for y in l + ("",) if x.casefold() != y.casefold())
+    return {x + y for x in l for y in l + ("",) if x.casefold() != y.casefold()}
 
 
 Whitespace = r"[ \f\t]*"
@@ -192,7 +188,7 @@ Coord = Tuple[int, int]
 
 
 def printtoken(
-    type: int, token: Text, srow_col: Coord, erow_col: Coord, line: Text
+    type: int, token: str, srow_col: Coord, erow_col: Coord, line: str
 ) -> None:  # for testing
     (srow, scol) = srow_col
     (erow, ecol) = erow_col
@@ -201,10 +197,10 @@ def printtoken(
     )
 
 
-TokenEater = Callable[[int, Text, Coord, Coord, Text], None]
+TokenEater = Callable[[int, str, Coord, Coord, str], None]
 
 
-def tokenize(readline: Callable[[], Text], tokeneater: TokenEater = printtoken) -> None:
+def tokenize(readline: Callable[[], str], tokeneater: TokenEater = printtoken) -> None:
     """
     The tokenize() function accepts two parameters: one representing the
     input stream, and one providing an output mechanism for tokenize().
@@ -224,17 +220,17 @@ def tokenize(readline: Callable[[], Text], tokeneater: TokenEater = printtoken)
 
 
 # backwards compatible interface
-def tokenize_loop(readline: Callable[[], Text], tokeneater: TokenEater) -> None:
+def tokenize_loop(readline: Callable[[], str], tokeneater: TokenEater) -> None:
     for token_info in generate_tokens(readline):
         tokeneater(*token_info)
 
 
-GoodTokenInfo = Tuple[int, Text, Coord, Coord, Text]
+GoodTokenInfo = Tuple[int, str, Coord, Coord, str]
 TokenInfo = Union[Tuple[int, str], GoodTokenInfo]
 
 
 class Untokenizer:
-    tokens: List[Text]
+    tokens: List[str]
     prev_row: int
     prev_col: int
 
@@ -250,13 +246,13 @@ class Untokenizer:
         if col_offset:
             self.tokens.append(" " * col_offset)
 
-    def untokenize(self, iterable: Iterable[TokenInfo]) -> Text:
+    def untokenize(self, iterable: Iterable[TokenInfo]) -> str:
         for t in iterable:
             if len(t) == 2:
                 self.compat(cast(Tuple[int, str], t), iterable)
                 break
             tok_type, token, start, end, line = cast(
-                Tuple[int, Text, Coord, Coord, Text], t
+                Tuple[int, str, Coord, Coord, str], t
             )
             self.add_whitespace(start)
             self.tokens.append(token)
@@ -266,7 +262,7 @@ class Untokenizer:
                 self.prev_col = 0
         return "".join(self.tokens)
 
-    def compat(self, token: Tuple[int, Text], iterable: Iterable[TokenInfo]) -> None:
+    def compat(self, token: Tuple[int, str], iterable: Iterable[TokenInfo]) -> None:
         startline = False
         indents = []
         toks_append = self.tokens.append
@@ -338,7 +334,7 @@ def detect_encoding(readline: Callable[[], bytes]) -> Tuple[str, List[bytes]]:
         try:
             return readline()
         except StopIteration:
-            return bytes()
+            return b''
 
     def find_cookie(line: bytes) -> Optional[str]:
         try:
@@ -387,7 +383,7 @@ def detect_encoding(readline: Callable[[], bytes]) -> Tuple[str, List[bytes]]:
     return default, [first, second]
 
 
-def untokenize(iterable: Iterable[TokenInfo]) -> Text:
+def untokenize(iterable: Iterable[TokenInfo]) -> str:
     """Transform tokens back into Python source code.
 
     Each element returned by the iterable must be a token sequence
@@ -410,7 +406,7 @@ def untokenize(iterable: Iterable[TokenInfo]) -> Text:
 
 
 def generate_tokens(
-    readline: Callable[[], Text], grammar: Optional[Grammar] = None
+    readline: Callable[[], str], grammar: Optional[Grammar] = None
 ) -> Iterator[GoodTokenInfo]:
     """
     The generate_tokens() generator requires one argument, readline, which