Exemple #1
0
# -*- coding: utf-8 -*-

'Tests for issue #8: prevent definitions of non-halting parsers.'

from funcparserlib.parser import (a, many, fwd, maybe, pure, oneplus,
                                  GrammarError, makes_progress, non_halting)
from funcparserlib.contrib.common import const
from nose.tools import ok_, assert_raises

x = a('x')
p1 = maybe(x)
p3 = maybe(x) + x
p4 = many(p3)
p5 = x | many(x)
p8 = x >> const(True)
p9 = pure(True)


def test_makes_progress():
    ok_(not makes_progress(p1))
    ok_(not makes_progress(p4))
    ok_(not makes_progress(p5))
    ok_(not makes_progress(p9))
    ok_(makes_progress(p3))
    ok_(makes_progress(p8))


def test_non_halting_many():
    assert_raises(GrammarError, lambda: many(many(x)).parse(''))
    assert_raises(GrammarError, lambda: oneplus(many(x)).parse(''))
    assert_raises(GrammarError, lambda: many(p1).parse(''))
Exemple #2
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    def sub(m):
        if m.group('standard') is not None:
            return std[m.group('standard')]
        else:
            return unichr(int(m.group('unicode'), 16))

    return re_esc.sub(sub, s)


def make_string(n):
    return unescape(n[1:-1])


# JSON Grammar
null = n('null') >> const(None)
true = n('true') >> const(True)
false = n('false') >> const(False)
number = sometok('number') >> make_number
string = sometok('string') >> make_string
value = fwd()
member = string + op_(':') + value >> tuple
object = (op_('{') + maybe(member + many(op_(',') + member)) + op_('}') >>
          make_object)
array = (
    op_('[') + maybe(value + many(op_(',') + value)) + op_(']') >> make_array)
value.define(null | true | false | object | array | number | string)
json_text = object | array
json_file = json_text + skip(eof)

name_parser_vars(locals())
Exemple #3
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    std = {
        '"': '"', '\\': '\\', '/': '/', 'b': '\b', 'f': '\f', 'n': '\n',
        'r': '\r', 't': '\t',
    }
    def sub(m):
        if m.group('standard') is not None:
            return std[m.group('standard')]
        else:
            return unichr(int(m.group('unicode'), 16))
    return re_esc.sub(sub, s)

def make_string(n):
    return unescape(n[1:-1])

# JSON Grammar
null = n('null') >> const(None)
true = n('true') >> const(True)
false = n('false') >> const(False)
number = sometok('number') >> make_number
string = sometok('string') >> make_string
value = fwd()
member = string + op_(':') + value >> tuple
object = (
    op_('{') +
    maybe(member + many(op_(',') + member)) +
    op_('}')
    >> make_object)
array = (
    op_('[') +
    maybe(value + many(op_(',') + value)) +
    op_(']')
Exemple #4
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        except ZeroDivisionError:
            return None
        return ret
    res = reduce(F, args, z)
    return res

eval = unarg(eval_expr)

number = sometok('number') >> make_number
name   = sometok('name')   >> make_name
string = sometok('string') >> make_string
func   = sometok('func')   >> make_func

value  = number | name | string

makeop = lambda s, f: op(s) >> const(f)

add = makeop('+', (ets.add, operator.add))
sub = makeop('-', (ets.sub, operator.sub))
mul = makeop('*', (ets.mul, operator.mul))
div = makeop('/', (ets.div, operator.div))

mul_op = mul | div
add_op = add | sub

args    = fwd()
factor  = fwd()
primary = value  
call    = func  + op_('(') + args + op_(')')  >> exec_func
term    = factor + many(mul_op + factor )  >> eval
expr    = term   + many(add_op + term   )  >> eval
# -*- coding: utf-8 -*-

'Tests for issue #8: prevent definitions of non-halting parsers.'

from funcparserlib.parser import (
        a, many, fwd, maybe, pure, oneplus, GrammarError, makes_progress,
        non_halting)
from funcparserlib.contrib.common import const
from nose.tools import ok_, assert_raises

x = a('x')
p1 = maybe(x)
p3 = maybe(x) + x
p4 = many(p3)
p5 = x | many(x)
p8 = x >> const(True)
p9 = pure(True)

def test_makes_progress():
    ok_(not makes_progress(p1))
    ok_(not makes_progress(p4))
    ok_(not makes_progress(p5))
    ok_(not makes_progress(p9))
    ok_(makes_progress(p3))
    ok_(makes_progress(p8))

def test_non_halting_many():
    assert_raises(GrammarError, lambda: many(many(x)).parse(''))
    assert_raises(GrammarError, lambda: oneplus(many(x)).parse(''))
    assert_raises(GrammarError, lambda: many(p1).parse(''))
    assert_raises(GrammarError, lambda: many(p5).parse(''))