Added stub for sre_parse and sre_constants(py3) (#1502)

* Added stub for sre_parse(py3)

* Fixed return type of SubPattern.__getitem__

* Typo

* Fix for issue related to error class

* Added stub for sre_constants(py3)

* Added missing import

stdlib/3/sre_constants.pyi

@@ -0,0 +1,40 @@
+# Source: https://github.com/python/cpython/blob/master/Lib/sre_constants.py
+
+from typing import Any, Dict, List, Optional, Union
+
+MAGIC = ...  # type: int
+
+class error(Exception):
+    msg = ...  # type: str
+    pattern = ...  # type: Optional[Union[str, bytes]]
+    pos = ...  # type: Optional[int]
+    lineno = ...  # type: int
+    colno = ...  # type: int
+    def __init__(self, msg: str, pattern: Union[str, bytes] = ..., pos: int = ...) -> None: ...
+
+class _NamedIntConstant(int):
+    name = ...  # type: Any
+    def __new__(cls, value: int, name: str): ...
+
+MAXREPEAT = ...  # type: _NamedIntConstant
+OPCODES = ...  # type: List[_NamedIntConstant]
+ATCODES = ...  # type: List[_NamedIntConstant]
+CHCODES = ...  # type: List[_NamedIntConstant]
+OP_IGNORE = ...  # type: Dict[_NamedIntConstant, _NamedIntConstant]
+AT_MULTILINE = ...  # type: Dict[_NamedIntConstant, _NamedIntConstant]
+AT_LOCALE = ...  # type: Dict[_NamedIntConstant, _NamedIntConstant]
+AT_UNICODE = ...  # type: Dict[_NamedIntConstant, _NamedIntConstant]
+CH_LOCALE = ...  # type: Dict[_NamedIntConstant, _NamedIntConstant]
+CH_UNICODE = ...  # type: Dict[_NamedIntConstant, _NamedIntConstant]
+SRE_FLAG_TEMPLATE = ...  # type: int
+SRE_FLAG_IGNORECASE = ...  # type: int
+SRE_FLAG_LOCALE = ...  # type: int
+SRE_FLAG_MULTILINE = ...  # type: int
+SRE_FLAG_DOTALL = ...  # type: int
+SRE_FLAG_UNICODE = ...  # type: int
+SRE_FLAG_VERBOSE = ...  # type: int
+SRE_FLAG_DEBUG = ...  # type: int
+SRE_FLAG_ASCII = ...  # type: int
+SRE_INFO_PREFIX = ...  # type: int
+SRE_INFO_LITERAL = ...  # type: int
+SRE_INFO_CHARSET = ...  # type: int

stdlib/3/sre_parse.pyi

@@ -0,0 +1,81 @@
+# Source: https://github.com/python/cpython/blob/master/Lib/sre_parse.py
+
+from typing import (
+    Any, Dict, FrozenSet, Iterable, List, Match,
+    Optional, Pattern as _Pattern, Tuple, Union
+)
+from sre_constants import _NamedIntConstant as NIC, error as _Error
+
+SPECIAL_CHARS = ...  # type: str
+REPEAT_CHARS = ...  # type: str
+DIGITS = ...  # type: FrozenSet[str]
+OCTDIGITS = ...  # type: FrozenSet[str]
+HEXDIGITS = ...  # type: FrozenSet[str]
+ASCIILETTERS = ...  # type: FrozenSet[str]
+WHITESPACE = ...  # type: FrozenSet[str]
+ESCAPES = ...  # type: Dict[str, Tuple[NIC, int]]
+CATEGORIES = ...  # type: Dict[str, Union[Tuple[NIC, NIC], Tuple[NIC, List[Tuple[NIC, NIC]]]]]
+FLAGS = ...  # type: Dict[str, int]
+GLOBAL_FLAGS = ...  # type: int
+
+class Verbose(Exception): ...
+
+class Pattern:
+    flags = ...  # type: int
+    groupdict = ...  # type: Dict[str, int]
+    groupwidths = ...  # type: List[Optional[int]]
+    lookbehindgroups = ...  # type: Optional[int]
+    def __init__(self) -> None: ...
+    @property
+    def groups(self) -> int: ...
+    def opengroup(self, name: str = ...) -> int: ...
+    def closegroup(self, gid: int, p: SubPattern) -> None: ...
+    def checkgroup(self, gid: int) -> bool: ...
+    def checklookbehindgroup(self, gid: int, source: Tokenizer) -> None: ...
+
+
+_OpSubpatternType = Tuple[Optional[int], int, int, SubPattern]
+_OpGroupRefExistsType = Tuple[int, SubPattern, SubPattern]
+_OpInType = List[Tuple[NIC, int]]
+_OpBranchType = Tuple[None, List[SubPattern]]
+_AvType = Union[_OpInType, _OpBranchType, Iterable[SubPattern], _OpGroupRefExistsType, _OpSubpatternType]
+_CodeType = Tuple[NIC, _AvType]
+
+
+class SubPattern:
+    pattern = ...  # type: Pattern
+    data = ...  # type: List[_CodeType]
+    width = ...  # type: Optional[int]
+    def __init__(self, pattern: Pattern, data: List[_CodeType] = ...) -> None: ...
+    def dump(self, level: int = ...) -> None: ...
+    def __len__(self) -> int: ...
+    def __delitem__(self, index: Union[int, slice]) -> None: ...
+    def __getitem__(self, index: Union[int, slice]) -> Union[SubPattern, _CodeType]: ...
+    def __setitem__(self, index: Union[int, slice], code: _CodeType) -> None: ...
+    def insert(self, index: int, code: _CodeType) -> None: ...
+    def append(self, code: _CodeType) -> None: ...
+    def getwidth(self) -> int: ...
+
+
+class Tokenizer:
+    istext = ...  # type: bool
+    string = ...  # type: Any
+    decoded_string = ...  # type: str
+    index = ...  # type: int
+    next = ...  # type: Optional[str]
+    def __init__(self, string: Any) -> None: ...
+    def match(self, char: str) -> bool: ...
+    def get(self) -> Optional[str]: ...
+    def getwhile(self, n: int, charset: Iterable[str]) -> str: ...
+    def getuntil(self, terminator: str) -> str: ...
+    @property
+    def pos(self) -> int: ...
+    def tell(self) -> int: ...
+    def seek(self, index: int) -> None: ...
+    def error(self, msg: str, offset: int = ...) -> _Error: ...
+
+def fix_flags(src: Union[str, bytes], flag: int) -> int: ...
+def parse(str: str, flags: int = ..., pattern: Pattern = ...) -> SubPattern: ...
+_TemplateType = Tuple[List[Tuple[int, int]], List[str]]
+def parse_template(source: str, pattern: _Pattern) -> _TemplateType: ...
+def expand_template(template: _TemplateType, match: Match) -> str: ...