Add GitHub Actions badge to README.md (#1134)

[etc/vim.git] / blib2to3 / pgen2 / pgen.py

diff --git a/blib2to3/pgen2/pgen.py b/blib2to3/pgen2/pgen.py
index 1da6925e5466d5022679fbfdac15965e7ee967fc..774cffc5e1cd991271d6e0be9b5e887a30e3d2fa 100644 (file)
--- a/blib2to3/pgen2/pgen.py
+++ b/blib2to3/pgen2/pgen.py
@@ -4,13 +4,40 @@
 # Pgen imports
 from . import grammar, token, tokenize
 
 # Pgen imports
 from . import grammar, token, tokenize
 

+from typing import (
+    Any,
+    Dict,
+    IO,
+    Iterable,
+    Iterator,
+    List,
+    Optional,
+    Text,
+    Tuple,
+    Union,
+    Sequence,
+    NoReturn,
+)
+from blib2to3.pgen2 import grammar
+from blib2to3.pgen2.tokenize import GoodTokenInfo
+import os
+
+
+Path = Union[str, "os.PathLike[str]"]
+

 
 class PgenGrammar(grammar.Grammar):
     pass
 
 
 class ParserGenerator(object):
 
 class PgenGrammar(grammar.Grammar):
     pass
 
 
 class ParserGenerator(object):

-    def __init__(self, filename, stream=None):
+
+    filename: Path
+    stream: IO[Text]
+    generator: Iterator[GoodTokenInfo]
+    first: Dict[Text, Optional[Dict[Text, int]]]
+
+    def __init__(self, filename: Path, stream: Optional[IO[Text]] = None) -> None:

         close_stream = None
         if stream is None:
             stream = open(filename)
         close_stream = None
         if stream is None:
             stream = open(filename)


@@ -25,7 +52,7 @@ class ParserGenerator(object):
         self.first = {}  # map from symbol name to set of tokens
         self.addfirstsets()
 
         self.first = {}  # map from symbol name to set of tokens
         self.addfirstsets()
 

-    def make_grammar(self):
+    def make_grammar(self) -> PgenGrammar:

         c = PgenGrammar()
         names = list(self.dfas.keys())
         names.sort()
         c = PgenGrammar()
         names = list(self.dfas.keys())
         names.sort()


@@ -50,8 +77,9 @@ class ParserGenerator(object):
         c.start = c.symbol2number[self.startsymbol]
         return c
 
         c.start = c.symbol2number[self.startsymbol]
         return c
 

-    def make_first(self, c, name):
+    def make_first(self, c: PgenGrammar, name: Text) -> Dict[int, int]:

         rawfirst = self.first[name]
         rawfirst = self.first[name]

+        assert rawfirst is not None

         first = {}
         for label in sorted(rawfirst):
             ilabel = self.make_label(c, label)
         first = {}
         for label in sorted(rawfirst):
             ilabel = self.make_label(c, label)


@@ -59,7 +87,7 @@ class ParserGenerator(object):
             first[ilabel] = 1
         return first
 
             first[ilabel] = 1
         return first
 

-    def make_label(self, c, label):
+    def make_label(self, c: PgenGrammar, label: Text) -> int:

         # XXX Maybe this should be a method on a subclass of converter?
         ilabel = len(c.labels)
         if label[0].isalpha():
         # XXX Maybe this should be a method on a subclass of converter?
         ilabel = len(c.labels)
         if label[0].isalpha():


@@ -105,7 +133,7 @@ class ParserGenerator(object):
                     c.tokens[itoken] = ilabel
                     return ilabel
 
                     c.tokens[itoken] = ilabel
                     return ilabel
 

-    def addfirstsets(self):
+    def addfirstsets(self) -> None:

         names = list(self.dfas.keys())
         names.sort()
         for name in names:
         names = list(self.dfas.keys())
         names.sort()
         for name in names:


@@ -113,11 +141,11 @@ class ParserGenerator(object):
                 self.calcfirst(name)
             # print name, self.first[name].keys()
 
                 self.calcfirst(name)
             # print name, self.first[name].keys()
 

-    def calcfirst(self, name):
+    def calcfirst(self, name: Text) -> None:

         dfa = self.dfas[name]
         self.first[name] = None  # dummy to detect left recursion
         state = dfa[0]
         dfa = self.dfas[name]
         self.first[name] = None  # dummy to detect left recursion
         state = dfa[0]

-        totalset = {}
+        totalset: Dict[str, int] = {}

         overlapcheck = {}
         for label, next in state.arcs.items():
             if label in self.dfas:
         overlapcheck = {}
         for label, next in state.arcs.items():
             if label in self.dfas:


@@ -128,12 +156,13 @@ class ParserGenerator(object):
                 else:
                     self.calcfirst(label)
                     fset = self.first[label]
                 else:
                     self.calcfirst(label)
                     fset = self.first[label]

+                    assert fset is not None

                 totalset.update(fset)
                 overlapcheck[label] = fset
             else:
                 totalset[label] = 1
                 overlapcheck[label] = {label: 1}
                 totalset.update(fset)
                 overlapcheck[label] = fset
             else:
                 totalset[label] = 1
                 overlapcheck[label] = {label: 1}

-        inverse = {}
+        inverse: Dict[str, str] = {}

         for label, itsfirst in overlapcheck.items():
             for symbol in itsfirst:
                 if symbol in inverse:
         for label, itsfirst in overlapcheck.items():
             for symbol in itsfirst:
                 if symbol in inverse:


@@ -145,9 +174,9 @@ class ParserGenerator(object):
                 inverse[symbol] = label
         self.first[name] = totalset
 
                 inverse[symbol] = label
         self.first[name] = totalset
 

-    def parse(self):
+    def parse(self) -> Tuple[Dict[Text, List["DFAState"]], Text]:

         dfas = {}
         dfas = {}

-        startsymbol = None
+        startsymbol: Optional[str] = None

         # MSTART: (NEWLINE | RULE)* ENDMARKER
         while self.type != token.ENDMARKER:
             while self.type == token.NEWLINE:
         # MSTART: (NEWLINE | RULE)* ENDMARKER
         while self.type != token.ENDMARKER:
             while self.type == token.NEWLINE:


@@ -167,9 +196,10 @@ class ParserGenerator(object):
             # print name, oldlen, newlen
             if startsymbol is None:
                 startsymbol = name
             # print name, oldlen, newlen
             if startsymbol is None:
                 startsymbol = name

+        assert startsymbol is not None

         return dfas, startsymbol
 
         return dfas, startsymbol
 

-    def make_dfa(self, start, finish):
+    def make_dfa(self, start: "NFAState", finish: "NFAState") -> List["DFAState"]:

         # To turn an NFA into a DFA, we define the states of the DFA
         # to correspond to *sets* of states of the NFA.  Then do some
         # state reduction.  Let's represent sets as dicts with 1 for
         # To turn an NFA into a DFA, we define the states of the DFA
         # to correspond to *sets* of states of the NFA.  Then do some
         # state reduction.  Let's represent sets as dicts with 1 for


@@ -177,12 +207,12 @@ class ParserGenerator(object):
         assert isinstance(start, NFAState)
         assert isinstance(finish, NFAState)
 
         assert isinstance(start, NFAState)
         assert isinstance(finish, NFAState)
 

-        def closure(state):
-            base = {}
+        def closure(state: NFAState) -> Dict[NFAState, int]:
+            base: Dict[NFAState, int] = {}

             addclosure(state, base)
             return base
 
             addclosure(state, base)
             return base
 

-        def addclosure(state, base):
+        def addclosure(state: NFAState, base: Dict[NFAState, int]) -> None:

             assert isinstance(state, NFAState)
             if state in base:
                 return
             assert isinstance(state, NFAState)
             if state in base:
                 return


@@ -193,7 +223,7 @@ class ParserGenerator(object):
 
         states = [DFAState(closure(start), finish)]
         for state in states:  # NB states grows while we're iterating
 
         states = [DFAState(closure(start), finish)]
         for state in states:  # NB states grows while we're iterating

-            arcs = {}
+            arcs: Dict[str, Dict[NFAState, int]] = {}

             for nfastate in state.nfaset:
                 for label, next in nfastate.arcs:
                     if label is not None:
             for nfastate in state.nfaset:
                 for label, next in nfastate.arcs:
                     if label is not None:


@@ -208,7 +238,7 @@ class ParserGenerator(object):
                 state.addarc(st, label)
         return states  # List of DFAState instances; first one is start
 
                 state.addarc(st, label)
         return states  # List of DFAState instances; first one is start
 

-    def dump_nfa(self, name, start, finish):
+    def dump_nfa(self, name: Text, start: "NFAState", finish: "NFAState") -> None:

         print("Dump of NFA for", name)
         todo = [start]
         for i, state in enumerate(todo):
         print("Dump of NFA for", name)
         todo = [start]
         for i, state in enumerate(todo):


@@ -224,14 +254,14 @@ class ParserGenerator(object):
                 else:
                     print("    %s -> %d" % (label, j))
 
                 else:
                     print("    %s -> %d" % (label, j))
 

-    def dump_dfa(self, name, dfa):
+    def dump_dfa(self, name: Text, dfa: Sequence["DFAState"]) -> None:

         print("Dump of DFA for", name)
         for i, state in enumerate(dfa):
             print("  State", i, state.isfinal and "(final)" or "")
             for label, next in sorted(state.arcs.items()):
                 print("    %s -> %d" % (label, dfa.index(next)))
 
         print("Dump of DFA for", name)
         for i, state in enumerate(dfa):
             print("  State", i, state.isfinal and "(final)" or "")
             for label, next in sorted(state.arcs.items()):
                 print("    %s -> %d" % (label, dfa.index(next)))
 

-    def simplify_dfa(self, dfa):
+    def simplify_dfa(self, dfa: List["DFAState"]) -> None:

         # This is not theoretically optimal, but works well enough.
         # Algorithm: repeatedly look for two states that have the same
         # set of arcs (same labels pointing to the same nodes) and
         # This is not theoretically optimal, but works well enough.
         # Algorithm: repeatedly look for two states that have the same
         # set of arcs (same labels pointing to the same nodes) and


@@ -252,7 +282,7 @@ class ParserGenerator(object):
                         changes = True
                         break
 
                         changes = True
                         break
 

-    def parse_rhs(self):
+    def parse_rhs(self) -> Tuple["NFAState", "NFAState"]:

         # RHS: ALT ('|' ALT)*
         a, z = self.parse_alt()
         if self.value != "|":
         # RHS: ALT ('|' ALT)*
         a, z = self.parse_alt()
         if self.value != "|":


@@ -269,7 +299,7 @@ class ParserGenerator(object):
                 z.addarc(zz)
             return aa, zz
 
                 z.addarc(zz)
             return aa, zz
 

-    def parse_alt(self):
+    def parse_alt(self) -> Tuple["NFAState", "NFAState"]:

         # ALT: ITEM+
         a, b = self.parse_item()
         while self.value in ("(", "[") or self.type in (token.NAME, token.STRING):
         # ALT: ITEM+
         a, b = self.parse_item()
         while self.value in ("(", "[") or self.type in (token.NAME, token.STRING):


@@ -278,7 +308,7 @@ class ParserGenerator(object):
             b = d
         return a, b
 
             b = d
         return a, b
 

-    def parse_item(self):
+    def parse_item(self) -> Tuple["NFAState", "NFAState"]:

         # ITEM: '[' RHS ']' | ATOM ['+' | '*']
         if self.value == "[":
             self.gettoken()
         # ITEM: '[' RHS ']' | ATOM ['+' | '*']
         if self.value == "[":
             self.gettoken()


@@ -298,7 +328,7 @@ class ParserGenerator(object):
             else:
                 return a, a
 
             else:
                 return a, a
 

-    def parse_atom(self):
+    def parse_atom(self) -> Tuple["NFAState", "NFAState"]:

         # ATOM: '(' RHS ')' | NAME | STRING
         if self.value == "(":
             self.gettoken()
         # ATOM: '(' RHS ')' | NAME | STRING
         if self.value == "(":
             self.gettoken()


@@ -315,8 +345,9 @@ class ParserGenerator(object):
             self.raise_error(
                 "expected (...) or NAME or STRING, got %s/%s", self.type, self.value
             )
             self.raise_error(
                 "expected (...) or NAME or STRING, got %s/%s", self.type, self.value
             )

+            assert False

 
 

-    def expect(self, type, value=None):
+    def expect(self, type: int, value: Optional[Any] = None) -> Text:

         if self.type != type or (value is not None and self.value != value):
             self.raise_error(
                 "expected %s/%s, got %s/%s", type, value, self.type, self.value
         if self.type != type or (value is not None and self.value != value):
             self.raise_error(
                 "expected %s/%s, got %s/%s", type, value, self.type, self.value


@@ -325,14 +356,14 @@ class ParserGenerator(object):
         self.gettoken()
         return value
 
         self.gettoken()
         return value
 

-    def gettoken(self):
+    def gettoken(self) -> None:

         tup = next(self.generator)
         while tup[0] in (tokenize.COMMENT, tokenize.NL):
             tup = next(self.generator)
         self.type, self.value, self.begin, self.end, self.line = tup
         # print token.tok_name[self.type], repr(self.value)
 
         tup = next(self.generator)
         while tup[0] in (tokenize.COMMENT, tokenize.NL):
             tup = next(self.generator)
         self.type, self.value, self.begin, self.end, self.line = tup
         # print token.tok_name[self.type], repr(self.value)
 

-    def raise_error(self, msg, *args):
+    def raise_error(self, msg: str, *args: Any) -> NoReturn:

         if args:
             try:
                 msg = msg % args
         if args:
             try:
                 msg = msg % args


@@ -342,17 +373,23 @@ class ParserGenerator(object):
 
 
 class NFAState(object):
 
 
 class NFAState(object):

-    def __init__(self):
+    arcs: List[Tuple[Optional[Text], "NFAState"]]
+
+    def __init__(self) -> None:

         self.arcs = []  # list of (label, NFAState) pairs
 
         self.arcs = []  # list of (label, NFAState) pairs
 

-    def addarc(self, next, label=None):
+    def addarc(self, next: "NFAState", label: Optional[Text] = None) -> None:

         assert label is None or isinstance(label, str)
         assert isinstance(next, NFAState)
         self.arcs.append((label, next))
 
 
 class DFAState(object):
         assert label is None or isinstance(label, str)
         assert isinstance(next, NFAState)
         self.arcs.append((label, next))
 
 
 class DFAState(object):

-    def __init__(self, nfaset, final):
+    nfaset: Dict[NFAState, Any]
+    isfinal: bool
+    arcs: Dict[Text, "DFAState"]
+
+    def __init__(self, nfaset: Dict[NFAState, Any], final: NFAState) -> None:

         assert isinstance(nfaset, dict)
         assert isinstance(next(iter(nfaset)), NFAState)
         assert isinstance(final, NFAState)
         assert isinstance(nfaset, dict)
         assert isinstance(next(iter(nfaset)), NFAState)
         assert isinstance(final, NFAState)


@@ -360,18 +397,18 @@ class DFAState(object):
         self.isfinal = final in nfaset
         self.arcs = {}  # map from label to DFAState
 
         self.isfinal = final in nfaset
         self.arcs = {}  # map from label to DFAState
 

-    def addarc(self, next, label):
+    def addarc(self, next: "DFAState", label: Text) -> None:

         assert isinstance(label, str)
         assert label not in self.arcs
         assert isinstance(next, DFAState)
         self.arcs[label] = next
 
         assert isinstance(label, str)
         assert label not in self.arcs
         assert isinstance(next, DFAState)
         self.arcs[label] = next
 

-    def unifystate(self, old, new):
+    def unifystate(self, old: "DFAState", new: "DFAState") -> None:

         for label, next in self.arcs.items():
             if next is old:
                 self.arcs[label] = new
 
         for label, next in self.arcs.items():
             if next is old:
                 self.arcs[label] = new
 

-    def __eq__(self, other):
+    def __eq__(self, other: Any) -> bool:

         # Equality test -- ignore the nfaset instance variable
         assert isinstance(other, DFAState)
         if self.isfinal != other.isfinal:
         # Equality test -- ignore the nfaset instance variable
         assert isinstance(other, DFAState)
         if self.isfinal != other.isfinal:


@@ -385,9 +422,9 @@ class DFAState(object):
                 return False
         return True
 
                 return False
         return True
 

-    __hash__ = None  # For Py3 compatibility.
+    __hash__: Any = None  # For Py3 compatibility.

 
 
 
 

-def generate_grammar(filename="Grammar.txt"):
+def generate_grammar(filename: Path = "Grammar.txt") -> PgenGrammar:

     p = ParserGenerator(filename)
     return p.make_grammar()
     p = ParserGenerator(filename)
     return p.make_grammar()