Decrease cost of ipynb code path when unneeded (#3748)

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

diff --git a/src/blib2to3/pgen2/parse.py b/src/blib2to3/pgen2/parse.py
index 8fe9667289796bf16d2186b17a81a3b8cf1a6ece..c462f63ad2c7fe43aef421060a750dc426a49036 100644 (file)
--- a/src/blib2to3/pgen2/parse.py
+++ b/src/blib2to3/pgen2/parse.py
@@ -32,7 +32,7 @@ from blib2to3.pgen2.grammar import Grammar
 from blib2to3.pytree import convert, NL, Context, RawNode, Leaf, Node
 
 if TYPE_CHECKING:
-    from blib2to3.driver import TokenProxy
+    from blib2to3.pgen2.driver import TokenProxy
 
 
 Results = Dict[Text, NL]
@@ -54,7 +54,7 @@ def stack_copy(
     stack: List[Tuple[DFAS, int, RawNode]]
 ) -> List[Tuple[DFAS, int, RawNode]]:
     """Nodeless stack copy."""
-    return [(copy.deepcopy(dfa), label, DUMMY_NODE) for dfa, label, _ in stack]
+    return [(dfa, label, DUMMY_NODE) for dfa, label, _ in stack]
 
 
 class Recorder:
@@ -114,7 +114,7 @@ class Recorder:
                     args.insert(0, ilabel)
                 func(*args)
 
-    def determine_route(self, value: Text = None, force: bool = False) -> Optional[int]:
+    def determine_route(self, value: Optional[Text] = None, force: bool = False) -> Optional[int]:
         alive_ilabels = self.ilabels
         if len(alive_ilabels) == 0:
             *_, most_successful_ilabel = self._dead_ilabels
@@ -269,6 +269,10 @@ class Parser(object):
                     break
 
                 next_token_type, next_token_value, *_ = proxy.eat(counter)
+                if next_token_type in (tokenize.COMMENT, tokenize.NL):
+                    counter += 1
+                    continue
+
                 if next_token_type == tokenize.OP:
                     next_token_type = grammar.opmap[next_token_value]