Staging
v0.5.1
v0.5.1
https://github.com/python/cpython
Revision cf58dfb44cc11d41ea1473cd7436618b210b8258 authored by Serhiy Storchaka on 15 June 2017, 14:16:38 UTC, committed by GitHub on 15 June 2017, 14:16:38 UTC
the original logic was just comparing the network address but this is wrong because if the network address is equal then we need to compare the ip address for breaking the tie add more ip_interface comparison tests. (cherry picked from commit 7bd8d3e794782582a4ad1c9749424fff86802c3e)
1 parent f75f6ed
Tip revision: cf58dfb44cc11d41ea1473cd7436618b210b8258 authored by Serhiy Storchaka on 15 June 2017, 14:16:38 UTC
[3.6] bpo-29931 fix __lt__ check in ipaddress.ip_interface for both v4 and v6. (GH-879) (#2217)
[3.6] bpo-29931 fix __lt__ check in ipaddress.ip_interface for both v4 and v6. (GH-879) (#2217)
Tip revision: cf58dfb
asdl.py
#-------------------------------------------------------------------------------
# Parser for ASDL [1] definition files. Reads in an ASDL description and parses
# it into an AST that describes it.
#
# The EBNF we're parsing here: Figure 1 of the paper [1]. Extended to support
# modules and attributes after a product. Words starting with Capital letters
# are terminals. Literal tokens are in "double quotes". Others are
# non-terminals. Id is either TokenId or ConstructorId.
#
# module ::= "module" Id "{" [definitions] "}"
# definitions ::= { TypeId "=" type }
# type ::= product | sum
# product ::= fields ["attributes" fields]
# fields ::= "(" { field, "," } field ")"
# field ::= TypeId ["?" | "*"] [Id]
# sum ::= constructor { "|" constructor } ["attributes" fields]
# constructor ::= ConstructorId [fields]
#
# [1] "The Zephyr Abstract Syntax Description Language" by Wang, et. al. See
# http://asdl.sourceforge.net/
#-------------------------------------------------------------------------------
from collections import namedtuple
import re
__all__ = [
'builtin_types', 'parse', 'AST', 'Module', 'Type', 'Constructor',
'Field', 'Sum', 'Product', 'VisitorBase', 'Check', 'check']
# The following classes define nodes into which the ASDL description is parsed.
# Note: this is a "meta-AST". ASDL files (such as Python.asdl) describe the AST
# structure used by a programming language. But ASDL files themselves need to be
# parsed. This module parses ASDL files and uses a simple AST to represent them.
# See the EBNF at the top of the file to understand the logical connection
# between the various node types.
builtin_types = {'identifier', 'string', 'bytes', 'int', 'object', 'singleton',
'constant'}
class AST:
def __repr__(self):
raise NotImplementedError
class Module(AST):
def __init__(self, name, dfns):
self.name = name
self.dfns = dfns
self.types = {type.name: type.value for type in dfns}
def __repr__(self):
return 'Module({0.name}, {0.dfns})'.format(self)
class Type(AST):
def __init__(self, name, value):
self.name = name
self.value = value
def __repr__(self):
return 'Type({0.name}, {0.value})'.format(self)
class Constructor(AST):
def __init__(self, name, fields=None):
self.name = name
self.fields = fields or []
def __repr__(self):
return 'Constructor({0.name}, {0.fields})'.format(self)
class Field(AST):
def __init__(self, type, name=None, seq=False, opt=False):
self.type = type
self.name = name
self.seq = seq
self.opt = opt
def __repr__(self):
if self.seq:
extra = ", seq=True"
elif self.opt:
extra = ", opt=True"
else:
extra = ""
if self.name is None:
return 'Field({0.type}{1})'.format(self, extra)
else:
return 'Field({0.type}, {0.name}{1})'.format(self, extra)
class Sum(AST):
def __init__(self, types, attributes=None):
self.types = types
self.attributes = attributes or []
def __repr__(self):
if self.attributes:
return 'Sum({0.types}, {0.attributes})'.format(self)
else:
return 'Sum({0.types})'.format(self)
class Product(AST):
def __init__(self, fields, attributes=None):
self.fields = fields
self.attributes = attributes or []
def __repr__(self):
if self.attributes:
return 'Product({0.fields}, {0.attributes})'.format(self)
else:
return 'Product({0.fields})'.format(self)
# A generic visitor for the meta-AST that describes ASDL. This can be used by
# emitters. Note that this visitor does not provide a generic visit method, so a
# subclass needs to define visit methods from visitModule to as deep as the
# interesting node.
# We also define a Check visitor that makes sure the parsed ASDL is well-formed.
class VisitorBase(object):
"""Generic tree visitor for ASTs."""
def __init__(self):
self.cache = {}
def visit(self, obj, *args):
klass = obj.__class__
meth = self.cache.get(klass)
if meth is None:
methname = "visit" + klass.__name__
meth = getattr(self, methname, None)
self.cache[klass] = meth
if meth:
try:
meth(obj, *args)
except Exception as e:
print("Error visiting %r: %s" % (obj, e))
raise
class Check(VisitorBase):
"""A visitor that checks a parsed ASDL tree for correctness.
Errors are printed and accumulated.
"""
def __init__(self):
super(Check, self).__init__()
self.cons = {}
self.errors = 0
self.types = {}
def visitModule(self, mod):
for dfn in mod.dfns:
self.visit(dfn)
def visitType(self, type):
self.visit(type.value, str(type.name))
def visitSum(self, sum, name):
for t in sum.types:
self.visit(t, name)
def visitConstructor(self, cons, name):
key = str(cons.name)
conflict = self.cons.get(key)
if conflict is None:
self.cons[key] = name
else:
print('Redefinition of constructor {}'.format(key))
print('Defined in {} and {}'.format(conflict, name))
self.errors += 1
for f in cons.fields:
self.visit(f, key)
def visitField(self, field, name):
key = str(field.type)
l = self.types.setdefault(key, [])
l.append(name)
def visitProduct(self, prod, name):
for f in prod.fields:
self.visit(f, name)
def check(mod):
"""Check the parsed ASDL tree for correctness.
Return True if success. For failure, the errors are printed out and False
is returned.
"""
v = Check()
v.visit(mod)
for t in v.types:
if t not in mod.types and not t in builtin_types:
v.errors += 1
uses = ", ".join(v.types[t])
print('Undefined type {}, used in {}'.format(t, uses))
return not v.errors
# The ASDL parser itself comes next. The only interesting external interface
# here is the top-level parse function.
def parse(filename):
"""Parse ASDL from the given file and return a Module node describing it."""
with open(filename) as f:
parser = ASDLParser()
return parser.parse(f.read())
# Types for describing tokens in an ASDL specification.
class TokenKind:
"""TokenKind is provides a scope for enumerated token kinds."""
(ConstructorId, TypeId, Equals, Comma, Question, Pipe, Asterisk,
LParen, RParen, LBrace, RBrace) = range(11)
operator_table = {
'=': Equals, ',': Comma, '?': Question, '|': Pipe, '(': LParen,
')': RParen, '*': Asterisk, '{': LBrace, '}': RBrace}
Token = namedtuple('Token', 'kind value lineno')
class ASDLSyntaxError(Exception):
def __init__(self, msg, lineno=None):
self.msg = msg
self.lineno = lineno or '<unknown>'
def __str__(self):
return 'Syntax error on line {0.lineno}: {0.msg}'.format(self)
def tokenize_asdl(buf):
"""Tokenize the given buffer. Yield Token objects."""
for lineno, line in enumerate(buf.splitlines(), 1):
for m in re.finditer(r'\s*(\w+|--.*|.)', line.strip()):
c = m.group(1)
if c[0].isalpha():
# Some kind of identifier
if c[0].isupper():
yield Token(TokenKind.ConstructorId, c, lineno)
else:
yield Token(TokenKind.TypeId, c, lineno)
elif c[:2] == '--':
# Comment
break
else:
# Operators
try:
op_kind = TokenKind.operator_table[c]
except KeyError:
raise ASDLSyntaxError('Invalid operator %s' % c, lineno)
yield Token(op_kind, c, lineno)
class ASDLParser:
"""Parser for ASDL files.
Create, then call the parse method on a buffer containing ASDL.
This is a simple recursive descent parser that uses tokenize_asdl for the
lexing.
"""
def __init__(self):
self._tokenizer = None
self.cur_token = None
def parse(self, buf):
"""Parse the ASDL in the buffer and return an AST with a Module root.
"""
self._tokenizer = tokenize_asdl(buf)
self._advance()
return self._parse_module()
def _parse_module(self):
if self._at_keyword('module'):
self._advance()
else:
raise ASDLSyntaxError(
'Expected "module" (found {})'.format(self.cur_token.value),
self.cur_token.lineno)
name = self._match(self._id_kinds)
self._match(TokenKind.LBrace)
defs = self._parse_definitions()
self._match(TokenKind.RBrace)
return Module(name, defs)
def _parse_definitions(self):
defs = []
while self.cur_token.kind == TokenKind.TypeId:
typename = self._advance()
self._match(TokenKind.Equals)
type = self._parse_type()
defs.append(Type(typename, type))
return defs
def _parse_type(self):
if self.cur_token.kind == TokenKind.LParen:
# If we see a (, it's a product
return self._parse_product()
else:
# Otherwise it's a sum. Look for ConstructorId
sumlist = [Constructor(self._match(TokenKind.ConstructorId),
self._parse_optional_fields())]
while self.cur_token.kind == TokenKind.Pipe:
# More constructors
self._advance()
sumlist.append(Constructor(
self._match(TokenKind.ConstructorId),
self._parse_optional_fields()))
return Sum(sumlist, self._parse_optional_attributes())
def _parse_product(self):
return Product(self._parse_fields(), self._parse_optional_attributes())
def _parse_fields(self):
fields = []
self._match(TokenKind.LParen)
while self.cur_token.kind == TokenKind.TypeId:
typename = self._advance()
is_seq, is_opt = self._parse_optional_field_quantifier()
id = (self._advance() if self.cur_token.kind in self._id_kinds
else None)
fields.append(Field(typename, id, seq=is_seq, opt=is_opt))
if self.cur_token.kind == TokenKind.RParen:
break
elif self.cur_token.kind == TokenKind.Comma:
self._advance()
self._match(TokenKind.RParen)
return fields
def _parse_optional_fields(self):
if self.cur_token.kind == TokenKind.LParen:
return self._parse_fields()
else:
return None
def _parse_optional_attributes(self):
if self._at_keyword('attributes'):
self._advance()
return self._parse_fields()
else:
return None
def _parse_optional_field_quantifier(self):
is_seq, is_opt = False, False
if self.cur_token.kind == TokenKind.Asterisk:
is_seq = True
self._advance()
elif self.cur_token.kind == TokenKind.Question:
is_opt = True
self._advance()
return is_seq, is_opt
def _advance(self):
""" Return the value of the current token and read the next one into
self.cur_token.
"""
cur_val = None if self.cur_token is None else self.cur_token.value
try:
self.cur_token = next(self._tokenizer)
except StopIteration:
self.cur_token = None
return cur_val
_id_kinds = (TokenKind.ConstructorId, TokenKind.TypeId)
def _match(self, kind):
"""The 'match' primitive of RD parsers.
* Verifies that the current token is of the given kind (kind can
be a tuple, in which the kind must match one of its members).
* Returns the value of the current token
* Reads in the next token
"""
if (isinstance(kind, tuple) and self.cur_token.kind in kind or
self.cur_token.kind == kind
):
value = self.cur_token.value
self._advance()
return value
else:
raise ASDLSyntaxError(
'Unmatched {} (found {})'.format(kind, self.cur_token.kind),
self.cur_token.lineno)
def _at_keyword(self, keyword):
return (self.cur_token.kind == TokenKind.TypeId and
self.cur_token.value == keyword)
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...